The Intelligent Resilient Framework (IRF) technology virtualizes multiple physical devices at the same layer into one virtual fabric to provide data center class availability and scalability. IRF virtualization technology offers processing power, interaction, unified management, and uninterrupted maintenance of multiple devices.

Figure 1 shows an IRF fabric that has two member devices, which appear as a single node to the upper-layer and lower-layer devices.

Figure 1 IRF application scenario

IRF provides the following benefits:

· Simplified topology and easy management—An IRF fabric appears as one node and is accessible at a single IP address on the network. You can use this IP address to log in at any member device to manage all the members of the IRF fabric. In addition, you do not need to run the spanning tree feature among the IRF members.

· 1:N redundancy—In an IRF fabric, one member acts as the master to manage and control the entire IRF fabric. All the other members process services while backing up the master. When the master fails, all the other member devices elect a new master from among them to take over without interrupting services.

· IRF link aggregation—You can assign several physical links between neighboring members to their IRF ports to create a load-balanced aggregate IRF connection with redundancy.

· Multichassis link aggregation—You can use the Ethernet link aggregation feature to aggregate the physical links between the IRF fabric and its upstream or downstream devices across the IRF members.

· Network scalability and resiliency—Processing capacity of an IRF fabric equals the total processing capacities of all the members. You can increase ports, network bandwidth, and processing capacity of an IRF fabric simply by adding member devices without changing the network topology.

Network topology

The device supports daisy-chain or ring topology for IRF fabrics. IRF does not support the full mesh topology. For information about connecting IRF member devices, see "Connecting IRF physical interfaces."

Basic concepts

IRF member roles

IRF uses two member roles: master and standby (called subordinate throughout the documentation).

When devices form an IRF fabric, they elect a master to manage and control the IRF fabric, and all the other devices back up the master. When the master device fails, the other devices elect a new master automatically. For more information about master election, see "Master election."

IRF member ID

An IRF fabric uses member IDs to uniquely identify and manage its members. This member ID information is included as the first part of interface numbers and file paths to uniquely identify interfaces and files in an IRF fabric. Two devices cannot form an IRF fabric if they use the same member ID. A device cannot join an IRF fabric if its member ID has been used in the fabric.

For more information, see "Interface naming conventions" and "File system naming conventions."

IRF port

An IRF port is a logical interface that connects IRF member devices. Every IRF-capable device has two IRF ports. The IRF ports are named IRF-port n/1 and IRF-port n/2, where n is the member ID of the device. The two IRF ports are referred to as IRF-port 1 and IRF-port 2 in this book.

To use an IRF port, you must bind a minimum of one physical interface to it. The physical interfaces assigned to an IRF port automatically form an aggregate IRF link. An IRF port goes down when all its IRF physical interfaces are down.

IRF physical interface

IRF physical interfaces connect IRF member devices and must be bound to an IRF port. They forward traffic between member devices, including IRF protocol packets and data packets that must travel across IRF member devices.

For more information about physical interfaces that can be used for IRF links, see "IRF physical interface requirements."

MAD

An IRF link failure causes an IRF fabric to split in two IRF fabrics operating with the same Layer 3 configurations, including the same IP address. To avoid IP address collision and network problems, IRF uses multi-active detection (MAD) mechanisms to detect the presence of multiple identical IRF fabrics, handle collisions, and recover from faults.

IRF domain ID

One IRF fabric forms one IRF domain. IRF uses IRF domain IDs to uniquely identify IRF fabrics and prevent IRF fabrics from interfering with one another.

As shown in Figure 2, IRF fabric 1 contains Device A and Device B, and IRF fabric 2 contains Device C and Device D. Both fabrics use the LACP aggregate links between them for MAD. When a member device receives an extended LACPDU for MAD, it checks the domain ID to see whether the packet is from the local IRF fabric. Then, the device can handle the packet correctly.

Figure 2 A network that contains two IRF domains

IRF split

IRF split occurs when an IRF fabric breaks up into multiple IRF fabrics because of IRF link failures, as shown in Figure 3. The split IRF fabrics operate with the same IP address. IRF split causes routing and forwarding problems on the network. To quickly detect a multi-active collision, configure a minimum of one MAD mechanism (see "Configuring MAD").

Figure 3 IRF split

IRF merge

IRF merge occurs when two split IRF fabrics reunite or when two independent IRF fabrics are united, as shown in Figure 4.

Figure 4 IRF merge

Member priority

Member priority determines the possibility of a member device to be elected the master. A member with higher priority is more likely to be elected the master.

Interface naming conventions

An interface is named in the chassis-number/slot-number/port-index format.

· chassis-number—IRF member ID of the device. This argument defaults to 1. The IRF member ID always takes effect, whether or not the device has formed an IRF fabric with other devices. If the device is alone, the device is regarded a one-chassis IRF fabric.

· slot-number—Slot number of the front panel or expansion interface card.

? The front panel slot number is fixed at 0 for all S7500E-XS switches.

? The expansion interface card slot numbers vary by device model.

- On an S7502E-XS switch, the slot numbers are 1 and 2, from left to right, when you face the slots.

- On an S7504E-XS switch, the slot numbers are 1 to 4, clockwise from the top left, when you face the slots.

· port-index—Index of the port on the device. Port index depends on the number of ports available on the device. To identify the index of a port, examine its port index mark on the chassis.

For example:

· On the single-chassis IRF fabric Sysname, FortyGigE 1/0/1 represents the first fixed port on the device. Set its link type to trunk, as follows:

<Sysname> system-view

[Sysname] interface fortygige 1/0/1

[Sysname-FortyGigE1/0/1] port link-type trunk

· On the multichassis IRF fabric Master, FortyGigE 3/0/1 represents the first fixed port on member device 3. Set its link type to trunk, as follows:

<Master> system-view

[Master] interface fortygige 3/0/1

[Master-FortyGigE3/0/1] port link-type trunk

File system naming conventions

On a single-chassis fabric, you can use its storage device name to access its file system.

On a multichassis IRF fabric, you can use the storage device name to access the file system of the master. To access the file system of any other member device, use the name in the slotmember-ID#storage-device-name format.

For example:

To access the test folder under the root directory of the flash memory on the master device:

<Master> mkdir test

Creating directory flash:/test... Done.

<Master> dir

Directory of flash:

0 -rw- 43548660 Jan 01 2011 08:21:29 system.ipe

1 drw- - Jan 01 2011 00:00:30 diagfile

2 -rw- 567 Jan 02 2011 01:41:54 dsakey

3 -rw- 735 Jan 02 2011 01:42:03 hostkey

4 -rw- 36 Jan 01 2011 00:07:52 ifindex.dat

5 -rw- 0 Jan 01 2011 00:53:09 lauth.dat

6 drw- - Jan 01 2011 06:33:55 log

7 drw- - Jan 02 2000 00:00:07 logfile

8 -rw- 23724032 Jan 01 2011 00:49:47 switch-cmw710-system.bin

9 drw- - Jan 01 2000 00:00:07 seclog

10 -rw- 591 Jan 02 2011 01:42:03 serverkey

11 -rw- 4609 Jan 01 2011 00:07:53 startup.cfg

12 -rw- 3626 Jan 01 2011 01:51:56 startup.cfg_bak

13 -rw- 78833 Jan 01 2011 00:07:53 startup.mdb

14 drw- - Jan 01 2011 00:15:48 test

25 drw- - Jan 01 2011 04:16:53 versionInfo

524288 KB total (365292 KB free)

To create and access the test folder under the root directory of the flash memory on member device 3:

<Master> mkdir slot3#flash:/test

Creating directory slot3#flash:/test... Done.

<Master> cd slot3#flash:/test

<Master> pwd

slot3#flash:/test

Or:

<Master> cd slot3#flash:/

<Master> mkdir test

Creating directory slot3#flash:/test... Done.

To copy the file test.ipe on the master to the root directory of the flash memory on member device 3:

# Display the current working path. In this example, the current working path is the root directory of the flash memory on member device 3.

<Master> pwd

slot3#flash:

# Change the current working path to the root directory of the flash memory on the master device.

<Master> cd flash:/

<Master> pwd

flash:

# Copy the file to member device 3.

<Master> copy test.ipe slot3#flash:/

Copy flash:/test.ipe to slot3#flash:/test.ipe?[Y/N]:y

Copying file flash:/test.ipe to slot3#flash:/test.ipe... Done.

For more information about storage device naming conventions, see Fundamentals Configuration Guide.

Configuration synchronization

IRF uses a strict running-configuration synchronization mechanism. In an IRF fabric, all devices obtain and run the running configuration of the master. Configuration changes are automatically propagated from the master to the remaining devices. The configuration files of these devices are retained, but the files do not take effect. The devices use their own startup configuration files only after they are removed from the IRF fabric.

For more information about configuration management, see Fundamentals Configuration Guide.

Loop elimination mechanism

Loop control protocols such as the spanning tree feature cannot be configured on IRF physical interfaces. However, IRF has its own mechanism to eliminate loops. Before an IRF member device forwards a packet, it identifies whether loops exist on the forwarding path based on the source and destination physical interfaces and the IRF topology. If a loop exists, the device discards the packet on the source interface of the looped path. This loop elimination mechanism will drop a large number of broadcast packets on the IRF physical interfaces. When you use SNMP tools, do not monitor packet forwarding on the IRF physical interfaces to reduce SNMP notifications of packet drops.

Master election

Master election occurs each time the IRF fabric topology changes in the following situations:

· The IRF fabric is established.

· The master device fails or is removed.

· The IRF fabric splits.

· Independent IRF fabrics merge.

NOTE:

Master election does not occur when two split IRF fabrics merge. All member devices in the Recovery-state IRF fabric automatically reboot to join the active IRF fabric as subordinate devices. The master device of the active IRF fabric is the master device of the merged IRF fabric.

Master election selects a master in descending order:

1. Current master, even if a new member has higher priority.

When an IRF fabric is being formed, all members consider themselves as the master. This rule is skipped.

2. Member with higher priority.

3. Member with the longest system uptime.

Two members are considered to start up at the same time if the difference between their startup times is equal to or less than 10 minutes. For these members, the next tiebreaker applies.

4. Member with the lowest CPU MAC address.

For the setup of a new IRF fabric, the subordinate devices must reboot to complete the setup after the master election.

For an IRF merge, devices must reboot if they are in the IRF fabric that fails the master election.

Multi-active handling procedure

The multi-active handling procedure includes detection, collision handling, and failure recovery.

Detection

MAD identifies each IRF fabric with a domain ID and an active ID (the member ID of the master). If multiple active IDs are detected in a domain, MAD determines that an IRF collision or split has occurred.

For more information about the MAD mechanisms and their application scenarios, see "MAD mechanisms."

Collision handling

When MAD detects a multi-active collision, it sets all IRF fabrics except one to the Recovery state. The fabric that is not placed in Recovery state can continue to forward traffic. The Recovery-state IRF fabrics are inactive and cannot forward traffic.

LACP MAD and BFD MAD use the following process to handle a multi-active collision:

1. Compare the number of members in each fabric.

2. Set all fabrics to the Recovery state except the one that has the most members.

3. Compare the member IDs of their masters if all IRF fabrics have the same number of members.

4. Set all fabrics to the Recovery state except the one that has the lowest numbered master.

5. Shut down all network ports and interfaces in the Recovery-state fabrics except for the following ports and interfaces:

? IRF physical interfaces.

? Ports and interfaces you have specified with the mad exclude interface command.

In contrast, ARP MAD and ND MAD do not compare the number of members in fabrics. These MAD mechanisms use the following process to handle a multi-active collision:

1. Compare the member IDs of the masters in the IRF fabrics.

2. Set all fabrics to the Recovery state except the one that has the lowest numbered master.

3. Take the same action on the network ports and interfaces in Recovery-state fabrics as LACP MAD and BFD MAD.

Failure recovery

To merge two split IRF fabrics, first repair the failed IRF link and remove the IRF link failure.

· If the IRF fabric in Recovery state fails before the failure is recovered, repair the failed IRF fabric and the failed IRF link.

· If the active IRF fabric fails before the failure is recovered, enable the inactive IRF fabric to take over the active IRF fabric. Then, recover the MAD failure.

MAD mechanisms

IRF provides MAD mechanisms by extending LACP, BFD, ARP, and IPv6 ND. You can configure a minimum of one MAD mechanism on an IRF fabric for prompt IRF split detection.

· Do not configure LACP MAD together with ARP MAD or ND MAD, because they handle collisions differently.

· Do not configure BFD MAD together with ARP MAD or ND MAD. BFD MAD is exclusive with the spanning tree feature. ARP MAD and ND MAD require the spanning tree feature. At the same time, BFD MAD handles collisions differently than ARP MAD and ND MAD.

Table 1 compares the MAD mechanisms and their application scenarios.

Table 1 Comparison of MAD mechanisms

MAD mechanism	Advantages	Disadvantages	Application scenario
LACP MAD	· Detection speed is fast. · Does not require MAD-dedicated physical links or Layer 3 interfaces.	Requires an intermediate device that supports extended LACP for MAD.	Link aggregation is used between the IRF fabric and its upstream or downstream device. For information about LACP, see Layer 2—LAN Switching Configuration Guide.
BFD MAD	· Detection speed is fast. · No intermediate device is required for two-chassis IRF fabrics. · Intermediate device, if used, can come from any vendor.	· Requires MAD dedicated physical links and Layer 3 interfaces, which cannot be used for transmitting user traffic. · If no intermediate device is used, any two IRF members must have a BFD MAD link to each other. · If an intermediate device is used, every IRF member must have a BFD MAD link to the intermediate device.	· No special requirements for network scenarios. · If no intermediate device is used, this mechanism is only suitable for two-chassis IRF fabrics that have members that are geographically close to one another. For information about BFD, see High Availability Configuration Guide.
ARP MAD	· No intermediate device is required for two-chassis IRF fabrics. · Intermediate device, if used, can come from any vendor. · Does not require MAD dedicated ports.	· Detection speed is slower than BFD MAD and LACP MAD. · The spanning tree feature must be enabled if common Ethernet ports are used for ARP MAD link.	If common Ethernet ports are used, this MAD mechanism is applicable only to the spanning tree-enabled non-link aggregation IPv4 network scenario. For information about ARP, see Layer 3—IP Services Configuration Guide.
ND MAD	· No intermediate device is required for two-chassis IRF fabrics. · Intermediate device, if used, can come from any vendor. · Does not require MAD dedicated ports.	· Detection speed is slower than BFD MAD and LACP MAD. · The spanning tree feature must be enabled.	Spanning tree-enabled non-link aggregation IPv6 network scenario.

LACP MAD

As shown in Figure 5, LACP MAD has the following requirements:

· Every IRF member must have a link with an intermediate device.

· All the links form a dynamic link aggregation group.

· The intermediate device must be a device that supports extended LACP for MAD.

The IRF member devices send extended LACPDUs that convey a domain ID and an active ID. The intermediate device transparently forwards the extended LACPDUs received from one member device to all the other member devices.

· If the domain IDs and active IDs sent by all the member devices are the same, the IRF fabric is integrated.

· If the extended LACPDUs convey the same domain ID but different active IDs, a split has occurred. LACP MAD handles this situation as described in "Collision handling."

Figure 5 LACP MAD scenario

BFD MAD

On a two-chassis IRF fabric, BFD MAD can work with or without intermediate devices. On an IRF fabric that has more than two member devices, BFD MAD must work with an intermediate device.

BFD MAD can be used on common Ethernet ports or management Ethernet ports.

Figure 6 shows a typical BFD MAD application scenario on common Ethernet ports. Figure 7 shows a typical BFD MAD application scenario on management Ethernet ports.

To use BFD MAD:

· Set up dedicated BFD MAD link between each pair of IRF members or between each IRF member and the intermediate device. Do not use the BFD MAD links for any other purposes.

· If common Ethernet ports are used for BFD MAD links, you must configure BFD MAD on a VLAN interface. Perform the following tasks:

? Assign the ports connected by BFD MAD links to the same VLAN.

? Create a VLAN interface for the VLAN, and assign a MAD IP address to each member on the VLAN interface.

On the intermediate device (if any), you must create the VLAN and assign the ports on the BFD MAD links to the VLAN.

· If management Ethernet ports are used for BFD MAD, assign a MAD IP address to each member device on the master's management Ethernet port. On the intermediate device (if any), assign the ports on the BFD links to the same VLAN.

NOTE:

· The MAD IP addresses identify the member devices and must belong to the same subnet.

· Of all management Ethernet ports on an IRF fabric, only the master's management Ethernet port is accessible.

With BFD MAD, the master attempts to establish BFD sessions with other member devices by using its MAD IP address as the source IP address.

· If the IRF fabric is integrated, only the MAD IP address of the master takes effect. The master cannot establish a BFD session with any other member. If you execute the display bfd session command, the state of the BFD sessions is Down.

· When the IRF fabric splits, the IP addresses of the masters in the split IRF fabrics take effect. The masters can establish a BFD session. If you execute the display bfd session command, the state of the BFD session between the two devices is Up.

Figure 6 BFD MAD scenario for common Ethernet ports

Figure 7 BFD MAD scenario for management Ethernet ports

ARP MAD

ARP MAD detects multi-active collisions by using extended ARP packets that convey the IRF domain ID and the active ID.

On a two-chassis IRF fabric, ARP MAD can work with or without an intermediate device. On an IRF fabric that has more than two member devices, ARP MAD must work with an intermediate device.

You can use common or management Ethernet ports for ARP MAD.

Figure 8 shows a typical ARP MAD scenario that uses an intermediate device.

To use ARP MAD:

· Set up ARP MAD links.

? If an intermediate device is used, connect each IRF member device to the intermediate device. For common Ethernet ports, run the spanning tree feature between the IRF fabric and the intermediate device. In this situation, data links can be used.

? If an intermediate device is not used, connect each IRF member device to all other member devices. In this situation, IRF links cannot be used for ARP MAD.

· If common Ethernet ports are used for ARP MAD links, you must configure ARP MAD on a VLAN interface. Perform the following tasks:

? Assign the ports connected by ARP MAD links to the same VLAN.

? Create a VLAN interface for the VLAN, and assign an IP address to the VLAN interface.

On the intermediate device (if any), you must create the VLAN and assign the ports on the ARP MAD links to the VLAN.

· If management Ethernet ports are used for ARP MAD, assign an IP address to the master's management Ethernet port. On the intermediate device (if any), assign the ports on the ARP MAD links to the same VLAN.

Each IRF member compares the domain ID and the active ID in incoming extended ARP packets with its domain ID and active ID.

· If the domain IDs are different, the extended ARP packet is from a different IRF fabric. The device does not continue to process the packet with the MAD mechanism.

· If the domain IDs are the same, the device compares the active IDs.

? If the active IDs are different, the IRF fabric has split.

? If the active IDs are the same, the IRF fabric is integrated.

Figure 8 ARP MAD scenario

ND MAD

ND MAD detects multi-active collisions by using NS packets to transmit the IRF domain ID and the active ID.

You can set up ND MAD links between neighbor IRF member devices or between each IRF member device and an intermediate device (see Figure 9). If an intermediate device is used, you must also run the spanning tree protocol between the IRF fabric and the intermediate device.

Each IRF member device compares the domain ID and the active ID in incoming NS packets with its domain ID and active ID:

· If the domain IDs are different, the NS packet is from a different IRF fabric. The device does not continue to process the packet with the MAD mechanism.

· If the domain IDs are the same, the device compares the active IDs:

? If the active IDs are different, the IRF fabric has split.

? If the active IDs are the same, the IRF fabric is integrated.

Figure 9 ND MAD scenario

General restrictions and configuration guidelines

For a successful IRF setup, follow the restrictions and guidelines in this section and the setup procedure in "Setup and configuration task list."

IRF fabric size

An S7500E-XS IRF fabric can contain a maximum of ten chassis. If the IRF physical interfaces exceed eight for an IRF port, the S7500E-XS IRF fabric can contain a maximum of two chassis.

Hardware compatibility

An H3C S7500E-XS switch can form an IRF fabric only with devices in the same series.

Software requirements

All IRF member devices must run the same software image version. Make sure the software auto-update feature is enabled on all member devices.

IRF physical interface requirements

Candidate IRF physical interfaces

Use the following physical interfaces for IRF links:

· 10-GE fiber ports.

· 40-GE fiber ports.

Selecting transceiver modules and cables

When you select transceiver modules and cables, follow these restrictions and guidelines:

· Use SFP+ or QSFP+ transceiver modules and fibers for a long-distance connection.

· Use SFP+ or QSFP+ DAC cables for a short-distance connection.

· Make sure the transceiver modules at the two ends of an IRF link are the same type. For more information about transceiver modules, see the device installation guide.

Connecting IRF ports

When you connect two neighboring IRF members, follow these restrictions and guidelines:

· You must connect the physical interfaces of IRF-port 1 on one member to the physical interfaces of IRF-port 2 on the other.

· Do not connect physical interfaces of both IRF ports on one member device to the physical interfaces of both IRF ports on the other device.

· Make sure the two ends of an aggregate IRF link have the same number of IRF physical interfaces.

Feature compatibility and configuration restrictions

ECMP

To form an IRF fabric, all member devices in the IRF fabric must support the same maximum number of ECMP routes. For more information about ECMP, see Layer 3—IP Routing Configuration Guide.

IRF mode

To form an IRF fabric, all member devices must use the same IRF mode setting, normal or enhanced.

To add a new device or replace a device, make sure the added device or replacement device is operating in the same IRF mode as the IRF fabric.

To use the IRF fabric as the parent fabric in an IRF 3 system, all member devices must operate in enhanced IRF mode. In enhanced IRF mode, an IRF fabric can contain a maximum of two member devices.

For more information about IRF modes, see "Setting up an IRF 3 system."

System operating mode

All member devices in the IRF fabric must work in the same system operating mode (set by using the system-working-mode command). For more information about the system operating mode, see Fundamentals Configuration Guide.

Licensing requirements

For a license-based feature to run correctly on an IRF fabric, make sure the licenses installed for the feature on all member devices are the same. For more information about feature licensing, see Fundamentals Configuration Guide.

Configuration backup

As a best practice, back up the next-startup configuration file on a device before adding the device to an IRF fabric as a subordinate.

A subordinate device's next-startup configuration file might be overwritten if the master and the subordinate use the same file name for their next-startup configuration files. You can use the backup file to restore the original configuration after removing the subordinate from the IRF fabric.

Setup and configuration task list

To set up an IRF fabric, perform the following tasks:

Tasks at a glance	Remarks
1. (Required.) Planning the IRF fabric setup	N/A
2. (Required.) Assigning a member ID to each IRF member device	Perform this task on each member device.
3. (Optional.) Specifying a priority for each member device	Perform this task on one or multiple member devices to affect the master election result.
4. (Optional.) Installing expansion interface cards	This task is beyond the scope of this document. For information about installing expansion interface cards, see the switch installation guide.
5. (Required.) Connecting IRF physical interfaces	N/A
6. (Required.) Binding physical interfaces to IRF ports	Perform this task on each member device. When you complete IRF port binding and activation on all IRF member devices, the IRF fabric is formed.
7. (Required.) Accessing the IRF fabric	When you log in to the IRF fabric, you are placed at the master's CLI, where you complete subsequent IRF settings and configure other features for the member devices as if they were one device.
8. (Optional.) Bulk-configuring basic IRF settings for a member device	N/A
9. (Optional.) Configuring a member device description	N/A
10. (Optional.) Configuring IRF link load sharing mode: ? Configuring the global load sharing mode ? Configuring a port-specific load sharing mode	N/A
11. (Optional.) Configuring the IRF bridge MAC address: ? Specifying a MAC address as the IRF bridge MAC address ? Configuring IRF bridge MAC persistence	N/A
12. (Optional.) Enabling software auto-update for software image synchronization	As a best practice, enable software auto-update to ensure system software image synchronization.
13. (Optional.) Setting the IRF link down report delay	N/A
14. (Optional.) Configuring MAD: ? Configuring LACP MAD ? Configuring BFD MAD ? Configuring ARP MAD ? Configuring ND MAD ? Excluding a network port or interface from the shutdown action upon detection of multi-active collision	MAD mechanisms are independent of one another. You can configure multiple MAD mechanisms for an IRF fabric.
15. (Optional.) Maintain an IRF fabric: ? Recovering an IRF fabric ? Removing an expansion interface card that has IRF physical interfaces ? Replacing an expansion interface card that has IRF physical interfaces	N/A

Planning the IRF fabric setup

Consider the following items when you plan an IRF fabric:

· Hardware compatibility and restrictions.

· IRF fabric size.

· Master device.

· IRF physical interfaces.

· Member ID and priority assignment scheme.

· Fabric topology and cabling scheme.

For more information about hardware and cabling, see the switch installation guide.

Assigning a member ID to each IRF member device

CAUTION:

In an IRF fabric, changing IRF member IDs might cause undesirable configuration changes and data loss. Before you do that, back up the configuration, and make sure you fully understand the impact on your network. For example, all member switches in an IRF fabric are the same model. If you swapped the IDs of any two members, their interface settings would also be swapped.

To create an IRF fabric, you must assign a unique IRF member ID to each member device.

To prevent any undesirable configuration change or data loss, avoid changing member IDs after the IRF fabric is formed.

The new member ID takes effect at a reboot. After the device reboots, the settings on all member ID-related physical resources (including common physical network ports) are removed, regardless of whether you have saved the configuration.

To assign a member ID to a device:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Assign a member ID to a member device.	irf member member-id renumber new-member-id	The default IRF member ID is 1.
3. (Optional.) Save the configuration.	save	If you have bound physical interfaces to IRF ports or assigned member priority, you must perform this step for these settings to take effect after the reboot.
4. Reboot the device.	reboot [ slot slot-number ] [ force ]	N/A

Specifying a priority for each member device

IRF member priority represents the possibility for a device to be elected the master in an IRF fabric. The higher the priority, the higher the possibility.

A change to member priority affects the election result at the next master election, but it does not cause an immediate master re-election.

To specify a priority for a member device:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Specify a priority for the device.	irf member member-id priority priority	The default IRF member priority is 1.

Connecting IRF physical interfaces

When you connect two neighboring IRF members, connect the physical interfaces of IRF-port 1 on one member to the physical interfaces of IRF-port 2 on the other (see Figure 10).

For example, you have four chassis: A, B, C, and D. IRF-port 1 and IRF-port 2 are represented by A1 and A2 on chassis A, represented by B1 and B2 on chassis B, and so on. To connect the four chassis into a ring topology of A-B-C-D(A), the IRF link cabling scheme must be one of the following:

· A1-B2, B1-C2, C1-D2, and D1-A2.

· A2-B1, B2-C1, C2-D1, and D2-A1.

IMPORTANT:

No intermediate devices are allowed between neighboring members.

Figure 10 Connecting IRF physical interfaces

Connect the devices into a daisy-chain topology or a ring topology. A ring topology is more reliable (see Figure 11). In ring topology, the failure of one IRF link does not cause the IRF fabric to split as in daisy-chain topology. Rather, the IRF fabric changes to a daisy-chain topology without interrupting network services.

To use the ring topology, you must have a minimum of three member devices.

Figure 11 Daisy-chain topology vs. ring topology

Binding physical interfaces to IRF ports

To establish an IRF connection between two devices, you must bind a minimum of one physical interface to IRF-port 1 on one device and to IRF-port 2 on the other.

You must configure IRF physical interfaces as Layer 2 interfaces. Layer 3 interfaces cannot be bound to IRF ports. To configure a physical interface as a Layer 2 interface, use the port link-mode bridge command. For more information about this command, see Interface Configuration Guide.

You can only execute the following commands on an IRF physical interface:

· Basic Ethernet interface commands:

? description

? flow-interval

? priority-flow-control

? priority-flow-control no-drop dot1p

? shutdown

For more information about these commands, see Interface Command Reference.

· LLDP commands:

? lldp admin-status

? lldp check-change-interval

? lldp enable

? lldp encapsulation snap

? lldp notification remote-change enable

? lldp tlv-enable

For more information about these commands, see Layer 2—LAN Switching Command Reference.

To bind physical interfaces to an IRF port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter interface view: interface interface-type interface-number	To shut down a range of IRF physical interfaces, enter interface range view. To shut down one IRF physical interface, enter its interface view.
3. Shut down the physical interfaces.	shutdown	If you cannot shut down a physical interface, follow the system instruction to shut down its peer interface.
4. Return to system view.	quit	N/A
5. Enter IRF port view.	irf-port member-id/port-number	N/A
6. Bind each physical interface to the IRF port.	port group interface interface-type interface-number [ mode { enhanced \| extended } ]	By default, no physical interfaces are bound to an IRF port. Repeat this step to assign multiple physical interfaces to the IRF port. You can bind a maximum of 16 physical interfaces to an IRF port. Make sure the two ends of an IRF link use the same binding mode. Make sure all physical interfaces bound to an IRF port use the same binding mode.
7. Return to system view.	quit	N/A
8. Enter Ethernet interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter interface view: interface interface-type interface-number	N/A
9. Bring up the physical interfaces.	undo shutdown	N/A
10. Return to system view.	quit	N/A
11. Save the running configuration.	save	Activating IRF port settings causes IRF merge and reboot. To avoid data loss, save the running configuration to the startup configuration file before you perform the operation.
12. Activate the configuration on the IRF port.	irf-port-configuration active	After this step is performed, the state of the IRF port changes to UP. The member devices elect a master, and the subordinate device reboots automatically. After the IRF fabric is formed, you can add physical interfaces to an IRF port (in UP state) without repeating this step.

Accessing the IRF fabric

The IRF fabric appears as one device after it is formed. You configure and manage all IRF members at the CLI of the master. All settings you have made are automatically propagated to the IRF members.

The following methods are available for accessing an IRF fabric:

· Local login—Log in through the console port of any member device.

· Remote login—Log in at a Layer 3 interface on any member device by using methods including Telnet and SNMP.

When you log in to an IRF fabric, you are placed at the CLI of the master, regardless of at which member device you are logged in.

For more information, see login configuration in Fundamentals Configuration Guide.

Bulk-configuring basic IRF settings for a member device

IMPORTANT:

The member device reboots immediately after you specify a new member ID for it. Make sure you are aware of the impact on the network.

Use the easy IRF feature to bulk-configure basic IRF settings for a member device, including the member ID, domain ID, priority, and IRF port bindings.

The easy IRF feature provides the following configuration methods:

· Interactive method—Enter the easy-irf command without parameters. The system will guide you to set the parameters step by step.

· Non-interactive method—Enter the easy-irf command with parameters.

As a best practice, use the interactive method if you are new to IRF.

When you specify IRF physical interfaces for an IRF port, you must follow the IRF port binding restrictions in "IRF physical interface requirements."

If you specify IRF physical interfaces by using the interactive method, you must also follow these restrictions and guidelines:

· Do not enter spaces between the interface type and interface number.

· Use a comma (,) to separate two physical interfaces. No spaces are allowed between interfaces.

To bulk-configure basic IRF settings for a device:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Bulk-configure basic IRF settings for the device.	easy-irf [ member member-id [ renumber new-member-id ] domain domain-id [ priority priority ] [ irf-port1 interface-list1 ] [ irf-port2 interface-list2 ] ]	Make sure the new member ID is unique in the IRF fabric to which the device will be added. If you execute this command multiple times, the following settings take effect: · The most recent settings for the member ID, domain ID, and priority. · IRF port bindings added through executions of the command. You can bind a maximum of 16 physical interfaces to an IRF port. To remove an IRF physical interface from an IRF port, you must use the undo port group interface command in IRF port view.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Bulk-configure basic IRF settings for the device.

easy-irf [ member member-id [ renumber new-member-id ] domain domain-id [ priority priority ] [ irf-port1 interface-list1 ] [ irf-port2 interface-list2 ] ]

Make sure the new member ID is unique in the IRF fabric to which the device will be added.

If you execute this command multiple times, the following settings take effect:

· The most recent settings for the member ID, domain ID, and priority.

· IRF port bindings added through executions of the command. You can bind a maximum of 16 physical interfaces to an IRF port.

To remove an IRF physical interface from an IRF port, you must use the undo port group interface command in IRF port view.

Configuring a member device description

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Configure a description for a member device.	irf member member-id description text	By default, no member device description is configured.

Configuring IRF link load sharing mode

On an IRF port, traffic is balanced across its physical links.

You can configure the IRF port to distribute traffic based on any combination of the following criteria:

· IP addresses.

· MAC addresses.

· Ingress ports.

The system displays an error message if a criteria combination is not supported.

Configure the IRF link load sharing mode for IRF links in system view or IRF port view:

· In system view, the configuration is global and takes effect on all IRF ports.

· In IRF port view, the configuration is port specific and takes effect only on the specified IRF port.

An IRF port preferentially uses the port-specific load sharing mode. If no port-specific load sharing mode is available, the IRF port uses the global load sharing mode.

Configuring the global load sharing mode

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Configure the global IRF link load sharing mode.	irf-port global load-sharing mode { destination-ip \| destination-mac \| ingress-port \| source-ip \| source-mac } *	The following are the default load sharing mode: · Non-IP traffic—Source and destination MAC addresses. · Non-TCP/-UDP IP traffic—Source and destination IP addresses. · TCP/UDP IP traffic—Source and destination service ports. If you execute this command multiple times, the most recent configuration takes effect.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Configure the global IRF link load sharing mode.

irf-port global load-sharing mode { destination-ip | destination-mac | ingress-port | source-ip | source-mac } *

The following are the default load sharing mode:

· Non-IP traffic—Source and destination MAC addresses.

· Non-TCP/-UDP IP traffic—Source and destination IP addresses.

· TCP/UDP IP traffic—Source and destination service ports.

If you execute this command multiple times, the most recent configuration takes effect.

Configuring a port-specific load sharing mode

Before you configure a port-specific load sharing mode, make sure you have bound a minimum of one physical interface to the IRF port.

To configure a port-specific load sharing mode for an IRF port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter IRF port view.	irf-port member-id/irf-port-number	N/A
3. Configure the port-specific load sharing mode.	irf-port load-sharing mode { destination-ip \| destination-mac \| ingress-port \| source-ip \| source-mac } *	The following are the default load sharing mode: · Non-IP traffic—Source and destination MAC addresses. · Non-TCP/-UDP IP traffic—Source and destination IP addresses. · TCP/UDP IP traffic—Source and destination service ports. If you execute this command multiple times, the most recent configuration takes effect.

Configuring the IRF bridge MAC address

CAUTION:

The bridge MAC address change causes transient traffic disruption.

Use this feature to configure the bridge MAC address of an IRF fabric. Layer 2 protocols, such as LACP, use the IRF bridge MAC address to identify an IRF fabric. On a switched LAN, the bridge MAC address must be unique.

When IRF fabrics merge, IRF ignores the IRF bridge MAC address and only checks the bridge MAC address of each member device in the IRF fabrics. IRF merge fails if any two member devices have the same bridge MAC address.

After IRF fabrics merge, the merged IRF fabric uses the bridge MAC address of the merging IRF fabric that won the master election as the IRF bridge MAC address.

The following methods are available to configure the IRF bridge MAC address for an IRF fabric:

· Specifying a MAC address as the IRF bridge MAC address.

The IRF fabric always uses the specified MAC address as the IRF bridge MAC address.

· Configuring IRF bridge MAC persistence.

This feature specifies the amount of time an IRF fabric can continue using a MAC address as the IRF bridge MAC address after the address owner leaves. By default, the bridge MAC address of the master device becomes the IRF bridge MAC address upon the setup of the IRF fabric.

Configuration restrictions and guidelines

When you configure the IRF bridge MAC address, follow these restrictions and guidelines:

· The IRF bridge MAC persistence feature does not take effect if you specify the IRF bridge MAC address by using the irf mac-address mac-address command.

· If ARP MAD or ND MAD is used with the spanning tree feature, you must configure IRF bridge MAC persistence by using the undo irf mac-address persistent command. Do not specify a MAC address as the IRF bridge MAC address.

· If TRILL is used, configure IRF bridge MAC persistence by using the irf mac-address persistent always command or specify a MAC address as the IRF bridge MAC address. The setting avoids unnecessary traffic disruption caused by IRF bridge MAC address changes on the TRILL network.

· If the IRF fabric has cross-member aggregate links, do not use the undo irf mac-address persistent command to avoid unnecessary traffic disruption.

Specifying a MAC address as the IRF bridge MAC address

You can specify the bridge MAC address of an existing IRF fabric for a new IRF fabric to replace the existing IRF fabric with transient packet loss.

To specify a MAC address as the IRF bridge MAC address:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Specify a MAC address as the IRF bridge MAC address.	irf mac-address mac-address	By default, an IRF fabric uses the bridge MAC address of the master as the IRF bridge MAC address. If an IRF fabric splits after you configure the IRF bridge MAC address, both the split IRF fabrics use the configured bridge MAC address as the IRF bridge MAC address.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Specify a MAC address as the IRF bridge MAC address.

irf mac-address mac-address

By default, an IRF fabric uses the bridge MAC address of the master as the IRF bridge MAC address.

If an IRF fabric splits after you configure the IRF bridge MAC address, both the split IRF fabrics use the configured bridge MAC address as the IRF bridge MAC address.

Configuring IRF bridge MAC persistence

Depending on the network condition, enable the IRF fabric to retain or change its bridge MAC address after the address owner leaves. Available options include:

· irf mac-address persistent timer—Bridge MAC address of the IRF fabric is retained for 6 minutes after the address owner leaves. If the owner does not return before the timer expires, the IRF fabric uses the bridge MAC address of the current master as its bridge MAC address. This option avoids unnecessary bridge MAC address changes caused by device reboot, transient link failure, or purposeful link disconnection.

· irf mac-address persistent always—Bridge MAC address of the IRF fabric does not change after the address owner leaves.

· undo irf mac-address persistent—Bridge MAC address of the current master replaces the original one as soon as the owner of the original bridge MAC address leaves.

To configure the IRF bridge MAC persistence setting:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Configure IRF bridge MAC persistence.	· Retain the bridge MAC address permanently even if the address owner has left the fabric: irf mac-address persistent always · Retain the bridge MAC address for 6 minutes after the address owner leaves the fabric: irf mac-address persistent timer · Change the bridge MAC address as soon as the address owner leaves the fabric: undo irf mac-address persistent	By default, the IRF bridge MAC address does not change after the address owner leaves the IRF fabric.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Configure IRF bridge MAC persistence.

· Retain the bridge MAC address permanently even if the address owner has left the fabric:
irf mac-address persistent always

· Retain the bridge MAC address for 6 minutes after the address owner leaves the fabric:
irf mac-address persistent timer

· Change the bridge MAC address as soon as the address owner leaves the fabric:
undo irf mac-address persistent

By default, the IRF bridge MAC address does not change after the address owner leaves the IRF fabric.

Enabling software auto-update for software image synchronization

IMPORTANT:

To ensure a successful software auto-update in a multi-user environment, prevent anyone from rebooting member devices during the auto-update process. To inform administrators of the auto-update status, configure the information center to output the status message to configuration terminals (see Network Management and Monitoring Configuration Guide).

The software auto-update feature automatically synchronizes the current software images of the master to devices that are attempting to join the IRF fabric.

To join an IRF fabric, a device must use the same software images as the master in the fabric.

When you add a device to the IRF fabric, software auto-update compares the startup software images of the device with the current software images of the IRF master. If the two sets of images are different, the device automatically performs the following operations:

1. Downloads the current software images of the master.

2. Sets the downloaded images as its main startup software images.

3. Reboots with the new software images to rejoin the IRF fabric.

You must manually update the new device with the software images running on the IRF fabric if software auto-update is disabled.

Configuration prerequisites

Make sure the device you are adding to the IRF fabric has sufficient storage space for the new software images.

If sufficient storage space is not available, the device automatically deletes the current software images. If the reclaimed space is still insufficient, the device cannot complete the auto-update. You must reboot the device, and then access the BootWare menus to delete files.

Configuration procedure

To enable software image synchronization:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enable software auto-update.	irf auto-update enable	By default, software auto-update is enabled.

Setting the IRF link down report delay

To prevent frequent IRF splits and merges during link flapping, configure the IRF ports to delay reporting link down events.

An IRF port does not report a link down event to the IRF fabric immediately after its link changes from up to down. If the IRF link state is still down when the delay is reached, the port reports the change to the IRF fabric.

IRF ports do not delay link up events. They report the link up event immediately after the IRF link comes up.

When you configure the IRF link down report delay, follow these restrictions and guidelines:

· Make sure the IRF link down report delay is shorter than the maximum CCM lifetime and BFD session lifetime. For more information about CFD and BFD, see High Availability Configuration Guide.

· As a best practice, set the delay to 0 seconds in the following situations:

? The IRF fabric requires a fast master/subordinate or IRF link switchover.

? The BFD, BFD MAD, GR, or RRPP feature is used.

To set the IRF link down report delay:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Set the IRF link down report delay.	irf link-delay interval	The default IRF link down report delay is 1 second. The greater the interval, the slower the service recovery.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Set the IRF link down report delay.

irf link-delay interval

The default IRF link down report delay is 1 second.

The greater the interval, the slower the service recovery.

Configuring MAD

When you configure MAD, follow these restrictions and guidelines:

· You can configure a minimum of one MAD mechanism on an IRF fabric for prompt IRF split detection.

? Do not configure LACP MAD together with ARP MAD or ND MAD, because they handle collisions differently.

? Do not configure BFD MAD together with ARP MAD or ND MAD. BFD MAD is exclusive with the spanning tree feature. ARP MAD and ND MAD require the spanning tree feature. At the same time, BFD MAD handles collisions differently than ARP MAD and ND MAD.

· If LACP MAD, ARP MAD, or ND MAD runs between two IRF fabrics, assign each fabric a unique IRF domain ID. (For BFD MAD, this task is optional.)

· An IRF fabric has only one IRF domain ID. You can change the IRF domain ID by using the following commands: irf domain, mad enable, mad arp enable, or mad nd enable. The IRF domain IDs configured by using these commands overwrite each other.

· To prevent a port or interface from being shut down when the IRF fabric transits to the Recovery state, use the mad exclude interface command. To bring up ports and interfaces in a Recovery-state IRF fabric, use the mad restore command instead of the undo shutdown command. The mad restore command activates the Recovery-state IRF fabric.

Configuring LACP MAD

When you use LACP MAD, follow these guidelines:

· The intermediate device must be a device that supports extended LACP for MAD.

· If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection.

· Use dynamic link aggregation mode. MAD is LACP dependent. Even though LACP MAD can be configured on both static and dynamic aggregate interfaces, it takes effect only on dynamic aggregate interfaces.

· Configure link aggregation settings on the intermediate device.

To configure LACP MAD:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Assign a domain ID to the IRF fabric.	irf domain domain-id	The default IRF domain ID is 0.
3. Create an aggregate interface and enter aggregate interface view.	· Enter Layer 2 aggregate interface view: interface bridge-aggregation interface-number · Enter Layer 3 aggregate interface view: interface route-aggregation interface-number	Perform this step also on the intermediate device.
4. Configure the aggregation group to operate in dynamic aggregation mode.	link-aggregation mode dynamic	By default, an aggregation group operates in static aggregation mode. Perform this step also on the intermediate device.
5. Enable LACP MAD.	mad enable	By default, LACP MAD is disabled.
6. Return to system view.	quit	N/A
7. Enter Ethernet interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter Ethernet interface view: interface interface-type interface-number	To assign a range of ports to the aggregation group, enter interface range view. To assign one port to the aggregation group, enter Ethernet interface view.
8. Assign the Ethernet port or the range of Ethernet ports to the specified aggregation group.	port link-aggregation group group-id	Multichassis link aggregation is allowed. Also perform this step on the intermediate device.

Configuring BFD MAD

Before you configure BFD MAD, choose a BFD MAD link scheme as described in "BFD MAD."

As a best practice, connect the BFD MAD links after you finish the BFD MAD configuration.

Configuring BFD MAD that uses common Ethernet ports

Configure BFD MAD on a VLAN interface if you use common Ethernet ports for BFD MAD.

When you configure BFD MAD settings, follow these restrictions and guidelines:

Category	Restrictions and guidelines
BFD MAD VLAN	· Do not enable BFD MAD on VLAN-interface 1. · If you are using an intermediate device, create the VLAN and VLAN interface on both the IRF fabric and the intermediate device. Assign the ports of BFD MAD links to the BFD MAD VLAN on both the IRF fabric and the intermediate device. · Make sure the IRF fabrics on the network use different BFD MAD VLANs. · Make sure the BFD MAD VLAN contains only ports on the BFD MAD links. Exclude a port from the BFD MAD VLAN if the port is not on the BFD MAD link. For example, if you have assigned the port to all VLANs by using the port trunk permit vlan all command, use the undo port trunk permit command to exclude the port from the BFD MAD VLAN.
BFD MAD VLAN and feature compatibility	Do not use the BFD MAD VLAN for any purpose other than configuring BFD MAD. · Configure only the mad bfd enable and mad ip address commands on the BFD MAD-enabled VLAN interface. If you configure other features, both BFD MAD and other features on the interface might run incorrectly. · Disable the spanning tree feature on any Layer 2 Ethernet ports in the BFD MAD VLAN. The MAD feature is mutually exclusive with the spanning tree feature. · Do not bind a BFD MAD-enabled VLAN interface to a VPN instance. The MAD feature is mutually exclusive with VPN.
MAD IP address	· To avoid problems, only use the mad ip address command to configure IP addresses on the BFD MAD-enabled VLAN interface. Do not configure an IP address by using the ip address command or configure a VRRP virtual address on the BFD MAD-enabled VLAN interface. · Make sure all the MAD IP addresses are on the same subnet. · MAD IP addresses must be unique among all IP addresses on the IRF fabric.
BFD MAD and IRF link down report delay restrictions	Set the IRF link down report delay to 0 seconds to avoid unnecessary recalculations.

To configure BFD MAD that uses common Ethernet ports:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. (Optional.) Assign a domain ID to the IRF fabric.	irf domain domain-id	By default, the domain ID of an IRF fabric is 0.
3. Set the IRF link down report delay to 0 seconds.	irf link-delay 0	The default IRF link down report delay is 1 second.
4. Create a VLAN dedicated to BFD MAD.	vlan vlan-id	The default VLAN on the device is VLAN 1.
5. Return to system view.	quit	N/A
6. Enter interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter interface view: interface interface-type interface-number	To assign a range of ports to the BFD MAD VLAN, enter interface range view. To assign one port to the BFD MAD VLAN, enter Ethernet interface view.
7. Assign the port or the range of ports to the BFD MAD VLAN.	· Assign the port to the VLAN as an access port: port access vlan vlan-id · Assign the port to the VLAN as a trunk port: port trunk permit vlan vlan-id · Assign the port to the VLAN as a hybrid port: port hybrid vlan vlan-id { tagged \| untagged }	The link type of BFD MAD ports can be access, trunk, or hybrid. The default link type of a port is access.
8. Return to system view.	quit	N/A
9. Enter VLAN interface view.	interface vlan-interface vlan-interface-id	N/A
10. Enable BFD MAD.	mad bfd enable	By default, BFD MAD is disabled.
11. Assign a MAD IP address to a member device on the VLAN interface.	mad ip address ip-address { mask \| mask-length } member member-id	By default, no MAD IP address is configured for a member device on a VLAN interface. Repeat this step to assign a MAD IP address to each member device on the VLAN interface.

Configuring BFD MAD that uses management Ethernet ports

When you configure BFD MAD that uses management Ethernet ports, follow these restrictions and guidelines:

Category	Restrictions and guidelines
Management Ethernet ports for BFD MAD	If you are using an intermediate device, connect the management Ethernet port on each member device to the common Ethernet ports on the intermediate device.
BFD MAD VLAN	· On the intermediate device (if any), create a VLAN for BFD MAD, and assign the ports used for BFD MAD to the VLAN. On the IRF fabric, you do not need to assign the management Ethernet ports to the VLAN. · As a best practice, do not configure other features on the VLAN used for BFD MAD for successful detection. · Make sure the IRF fabrics on the network use different BFD MAD VLANs.
BFD MAD-enabled management Ethernet port and feature compatibility	Do not bind a BFD MAD-enabled management Ethernet port to a VPN instance. The MAD feature is mutually exclusive with VPN.
MAD IP address	· Use the mad ip address command instead of the ip address command to configure MAD IP addresses on the BFD MAD-enabled management Ethernet ports. · Make sure all the MAD IP addresses are on the same subnet. · MAD IP addresses must be unique among all IP addresses on the IRF fabric.
BFD MAD and IRF link down report delay restrictions	Set the IRF link down report delay to 0 seconds to avoid unnecessary recalculations.

To configure BFD MAD that uses management Ethernet ports:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. (Optional.) Assign a domain ID to the IRF fabric.	irf domain domain-id	By default, the domain ID of an IRF fabric is 0.
3. Set the IRF link down report delay to 0 seconds.	irf link-delay 0	The default IRF link down report delay is 1 second.
4. Enter management Ethernet interface view.	interface M-GigabitEthernet interface-number	Of all management Ethernet ports on an IRF fabric, only the master's management Ethernet port is accessible.
5. Enable BFD MAD.	mad bfd enable	By default, BFD MAD is disabled.
6. Assign a MAD IP address to each member device.	mad ip address ip-address { mask \| mask-length } member member-id	By default, no MAD IP address is configured for any member device.

Configuring ARP MAD

Before you configure ARP MAD, choose an ARP MAD link scheme as described in "ARP MAD."

As a best practice, connect the ARP MAD links after you finish the ARP MAD configuration if you are not using existing data links as ARP MAD links.

Configuring ARP MAD that uses common Ethernet ports

Configure ARP MAD on a VLAN interface if you use common Ethernet ports for ARP MAD.

When you configure ARP MAD that uses common Ethernet ports, follow these restrictions and guidelines:

Category	Restrictions and guidelines
ARP MAD VLAN	· Do not enable ARP MAD on VLAN-interface 1. · If you are using an intermediate device, perform the following tasks on both the IRF fabric and the intermediate device: ? Create a VLAN and VLAN interface for ARP MAD. ? Assign the ports of ARP MAD links to the ARP MAD VLAN. · Do not use the ARP MAD VLAN for any other purposes.
ARP MAD and feature configuration	If an intermediate device is used, make sure the following requirements are met: · Run the spanning tree feature between the IRF fabric and the intermediate device to ensure that there is only one ARP MAD link in forwarding state. For more information about the spanning tree feature and its configuration, see Layer 2—LAN Switching Configuration Guide. · Enable the IRF fabric to change its bridge MAC address as soon as the address owner leaves. · If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection.

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Assign a domain ID to the IRF fabric.	irf domain domain-id	The default IRF domain ID is 0.
3. Configure the IRF bridge MAC address to change as soon as the address owner leaves.	undo irf mac-address persistent	By default, the IRF bridge MAC address does not change after the address owner leaves.
4. Create a VLAN dedicated to ARP MAD.	vlan vlan-id	The default VLAN on the device is VLAN 1.
5. Return to system view.	quit	N/A
6. Enter Ethernet interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter interface view: interface interface-type interface-number	To assign a range of ports to the ARP MAD VLAN, enter interface range view. To assign one port to the ARP MAD VLAN, enter Ethernet interface view.
7. Assign the port or the range of ports to the ARP MAD VLAN.	· Assign the port to the VLAN as an access port: port access vlan vlan-id · Assign the port to the VLAN as a trunk port: port trunk permit vlan vlan-id · Assign the port to the VLAN as a hybrid port: port hybrid vlan vlan-id { tagged \| untagged }	The link type of ARP MAD ports can be access, trunk, or hybrid. The default link type of a port is access.
8. Return to system view.	quit	N/A
9. Enter VLAN interface view.	interface vlan-interface vlan-interface-id	N/A
10. Assign the interface an IP address.	ip address ip-address { mask \| mask-length }	By default, no IP addresses are assigned to a VLAN interface.
11. Enable ARP MAD.	mad arp enable	By default, ARP MAD is disabled.

Configuring ARP MAD that uses management Ethernet ports

When you configure ARP MAD that uses management Ethernet ports, follow these restrictions and guidelines:

Category	Restrictions and guidelines
Ports on the intermediate device for ARP MAD	Use common Ethernet ports on the intermediate device to connect the management Ethernet ports on the IRF fabric.
ARP MAD VLAN	On the intermediate device, create a VLAN for ARP MAD, and assign the ports used for ARP MAD to the VLAN. On the IRF fabric, you do not need to assign the management Ethernet ports to the VLAN.
ARP MAD and feature configuration	· Enable the IRF fabric to change its bridge MAC address as soon as the address owner leaves. · If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection.

To configure ARP MAD that uses management Ethernet ports:

Step	Command		Remarks
1. Enter system view.	system-view		N/A
2. Assign a domain ID to the IRF fabric.	irf domain domain-id		By default, the domain ID of an IRF fabric is 0.
3. Configure the IRF bridge MAC address to change as soon as the address owner leaves.		undo irf mac-address persistent	By default, the IRF bridge MAC address does not change after the address owner leaves.
4. Enter management Ethernet interface view.	interface M-GigabitEthernet interface-number		Of all management Ethernet ports on an IRF fabric, only the master's management Ethernet port is accessible.
5. Assign an IP address to the management Ethernet ports.	ip address ip-address { mask \| mask-length }		By default, no IP addresses are configured.
6. Enable ARP MAD.	mad arp enable		By default, ARP MAD is disabled.

Configuring ND MAD

When you use ND MAD, follow these guidelines:

· Do not configure ND MAD on VLAN-interface 1.

· Do not use the VLAN configured for ND MAD for any other purposes.

· If an intermediate device is used, you can use common data links as ND MAD links. If no intermediate device is used, set up dedicated ND MAD links between IRF member devices.

· If an intermediate device is used, make sure the following requirements are met:

? Run the spanning tree feature between the IRF fabric and the intermediate device. Make sure there is only one ND MAD link in forwarding state. For more information about the spanning tree feature and its configuration, see Layer 2—LAN Switching Configuration Guide.

? Enable the IRF fabric to change its bridge MAC address as soon as the bridge MAC owner leaves.

? Create an ND MAD VLAN and assign the ports on the ND MAD links to the VLAN.

? If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection.

To configure ND MAD:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Assign a domain ID to the IRF fabric.	irf domain domain-id	The default IRF domain ID is 0.
3. Configure the IRF bridge MAC address to change as soon as the address owner leaves.	undo irf mac-address persistent	By default, the IRF bridge MAC address does not change after the address owner leaves.
4. Create a VLAN dedicated to ND MAD.	vlan vlan-id	The default VLAN on the device is VLAN 1.
5. Return to system view.	quit	N/A
6. Enter Ethernet interface view or interface range view.	· Enter interface range view: ? Method 1: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ? Method 2: interface range name name [ interface { interface-type interface-number [ to interface-type interface-number ] } &<1-24> ] · Enter interface view: interface interface-type interface-number	To assign a range of ports to the ND MAD VLAN, enter interface range view. To assign one port to the ND MAD VLAN, enter Ethernet interface view.
7. Assign the port or the range of ports to the ND MAD VLAN.	· Assign the port to the VLAN as an access port: port access vlan vlan-id · Assign the port to the VLAN as a trunk port: port trunk permit vlan vlan-id · Assign the port to the VLAN as a hybrid port: port hybrid vlan vlan-id { tagged \| untagged }	The link type of ND MAD ports can be access, trunk, or hybrid. The default link type of a port is access.
8. Return to system view.	quit	N/A
9. Enter VLAN interface view.	interface vlan-interface vlan-interface-id	N/A
10. Assign the interface an IPv6 address.	ipv6 address { ipv6-address/pre-length \| ipv6 address pre-length }	By default, no IPv6 addresses are assigned to a VLAN interface.
11. Enable ND MAD.	mad nd enable	By default, ND MAD is disabled.

Excluding a network port or interface from the shutdown action upon detection of multi-active collision

By default, all ports and interfaces except the console port and IRF physical interfaces shut down automatically when the IRF fabric transits to the Recovery state.

You can exclude a network port or interface from the shutdown action for management or other special purposes. For example:

· Exclude a port from the shutdown action so you can Telnet to the port for managing the device.

· Exclude a VLAN interface and its Layer 2 ports from the shutdown action so you can log in through the VLAN interface.

Configuration restrictions and guidelines

When you configure this feature, follow these restrictions and guidelines:

· If the Layer 2 ports of a VLAN interface are distributed on multiple member devices, the exclusion operation might introduce IP collision risks. The VLAN interface might be up on both active and inactive IRF fabrics.

· Do not exclude the following ports and interfaces from the shutdown action:

? Aggregate interfaces used for MAD and their member ports.

? VLAN interfaces used for MAD and the Ethernet ports in the VLANs.

? Management Ethernet ports used for MAD.

Configuration procedure

To configure a network port or interface to not shut down when the IRF fabric transits to the Recovery state:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Configure a network port or interface to not shut down when the IRF fabric transits to the Recovery state.	mad exclude interface interface-type interface-number	By default, all network ports and interfaces on a Recovery-state IRF fabric are shut down, except for the IRF physical interfaces and console port.

Recovering an IRF fabric

After the failed IRF link between two split IRF fabrics is recovered, the member devices on the inactive IRF fabric automatically reboot. After these member devices join the active IRF fabric as subordinates, IRF merge is complete, as shown in Figure 12.

Figure 12 Recovering the IRF fabric

If the active IRF fabric fails before the IRF link is recovered (see Figure 13), use the mad restore command on the inactive IRF fabric to recover the inactive IRF fabric. The command also brings up all network ports and interfaces that were shut down by MAD. After you repair the IRF link, the two parts merge into a unified IRF fabric.

Figure 13 Active IRF fabric fails before the IRF link is recovered

To manually recover an inactive IRF fabric:

Step	Command
1. Enter system view.	system-view
2. Recover the inactive IRF fabric.	mad restore

After the IRF fabric is recovered, all ports and interfaces that have been shut down by MAD come up automatically.

Removing an expansion interface card that has IRF physical interfaces

To remove an expansion interface card that provides IRF physical interfaces:

1. Perform one of the following tasks to eliminate temporary packet loss:

? Remove cables from the IRF physical interfaces on the card.

? Shut down the IRF physical interfaces on the card by using the shutdown command.

2. Remove the card.

Replacing an expansion interface card that has IRF physical interfaces

To replace the old card with a different model replacement card:

1. Shut down the IRF physical interfaces on the old card by using the shutdown command.

2. Remove the IRF port bindings that contain the physical interfaces.

3. Remove the old card, and then install the replacement card.

4. Verify that the replacement card has been correctly installed by using the display device command.

5. Reconfigure the IRF port bindings, as described in "Binding physical interfaces to IRF ports."

6. Activate the IRF port settings by using the irf-port-configuration active command.

You may skip this step if the IRF port is in UP state when you add bindings.

To replace the old card with the same model replacement card:

1. Shut down the IRF physical interfaces on the old card by using the shutdown command.

2. Remove the old card, and then install the replacement card.

3. Verify that the replacement card has been correctly installed by using the display device command.

4. Bring up the physical interfaces by using the undo shutdown command after the interface card completes startup.

Displaying and maintaining an IRF fabric

Execute display commands in any view.

Task	Command
Display information about all IRF members.	display irf
Display the IRF fabric topology.	display irf topology
Display IRF link information.	display irf link
Display IRF configuration.	display irf configuration
Display load sharing mode for IRF links.	display irf-port load-sharing mode [ irf-port [ member-id/irf-port-number ] ]
Display MAD configuration.	display mad [ verbose ]

Configuration examples

This section provides IRF configuration examples for IRF fabrics that use different MAD mechanisms.

LACP MAD-enabled IRF configuration example

Network requirements

As shown in Figure 14, set up a four-chassis IRF fabric at the access layer of the enterprise network.

Configure LACP MAD on the multichassis aggregation to Device E, an H3C device that supports extended LACP.

Figure 14 Network diagram

Configuration procedure

1. Configure Device A:

# Shut down the physical interfaces used for IRF links in batch. For information about bulk Ethernet port configuration, see Layer 2—LAN Switching Configuration Guide.

<Sysname> system-view

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 1/1/1 and FortyGigE 1/1/2 to IRF-port 1/1.

[Sysname] irf-port 1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/2

[Sysname-irf-port1/1] quit

# Bind FortyGigE 1/1/3 and FortyGigE 1/1/4 to IRF-port 1/2.

[Sysname] irf-port 1/2

[Sysname-irf-port1/2] port group interface fortygige 1/1/3

[Sysname-irf-port1/2] port group interface fortygige 1/1/4

[Sysname-irf-port1/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

2. Configure Device B:

# Change the member ID of Device B to 2 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 2

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device B to Device A as shown in Figure 14, and log in to Device B.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 2/1/1 and FortyGigE 2/1/2 to IRF-port 2/1.

[Sysname] irf-port 2/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/2

[Sysname-irf-port2/1] quit

# Bind FortyGigE 2/1/3 and FortyGigE 2/1/4 to IRF-port 2/2.

[Sysname] irf-port 2/2

[Sysname-irf-port2/2] port group interface fortygige 2/1/3

[Sysname-irf-port2/2] port group interface fortygige 2/1/4

[Sysname-irf-port2/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

The two devices perform master election, and the one that has lost the election reboots to form an IRF fabric with the master.

3. Configure Device C:

# Change the member ID of Device C to 3 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 3

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device C to Device A as shown in Figure 14, and log in to Device C.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 3/1/1 and FortyGigE 3/1/2 to IRF-port 3/1.

[Sysname] irf-port 3/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/2

[Sysname-irf-port3/1] quit

# Bind FortyGigE 3/1/3 and FortyGigE 3/1/4 to IRF-port 3/2.

[Sysname] irf-port 3/2

[Sysname-irf-port3/2] port group interface fortygige 3/1/3

[Sysname-irf-port3/2] port group interface fortygige 3/1/4

[Sysname-irf-port3/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device C reboots to join the IRF fabric.

4. Configure Device D:

# Change the member ID of Device D to 4 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 4

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device D to Device B and Device C as shown in Figure 14, and log in to Device D.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 4/1/1 and FortyGigE 4/1/2 to IRF-port 4/1.

[Sysname] irf-port 4/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/2

[Sysname-irf-port4/1] quit

# Bind FortyGigE 4/1/3 and FortyGigE 4/1/4 to IRF-port 4/2.

[Sysname] irf-port 4/2

[Sysname-irf-port4/2] port group interface fortygige 4/1/3

[Sysname-irf-port4/2] port group interface fortygige 4/1/4

[Sysname-irf-port4/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device D reboots to join the IRF fabric. A four-chassis IRF fabric is formed.

5. Configure LACP MAD on the IRF fabric:

# Set the domain ID of the IRF fabric to 1.

<Sysname> system-view

[Sysname] irf domain 1

# Create a dynamic aggregate interface and enable LACP MAD.

[Sysname] interface bridge-aggregation 2

[Sysname-Bridge-Aggregation2] link-aggregation mode dynamic

[Sysname-Bridge-Aggregation2] mad enable

You need to assign a domain ID (range: 0-4294967295)

[Current domain is: 1]:

The assigned domain ID is: 1

Info: MAD LACP only enable on dynamic aggregation interface.

[Sysname-Bridge-Aggregation2] quit

# Assign FortyGigE 1/1/5, FortyGigE 2/1/5, FortyGigE 3/1/5, and FortyGigE 4/1/5 to the aggregate interface.

[Sysname] interface range fortygige 1/1/5 fortygige 2/1/5 fortygige 3/1/5 fortygige 4/1/5

[Sysname-if-range] port link-aggregation group 2

[Sysname-if-range] quit

6. Configure Device E as the intermediate device:

CAUTION:

If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection. False detection causes IRF split.

# Create a dynamic aggregate interface.

<Sysname> system-view

[Sysname] interface bridge-aggregation 2

[Sysname-Bridge-Aggregation2] link-aggregation mode dynamic

[Sysname-Bridge-Aggregation2] quit

# Assign FortyGigE 1/1/1 through FortyGigE 1/1/4 to the aggregate interface.

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] port link-aggregation group 2

[Sysname-if-range] quit

BFD MAD-enabled IRF configuration example

Network requirements

As shown in Figure 15, set up an IRF fabric at the distribution layer of the network.

· Configure BFD MAD in the IRF fabric and set up BFD MAD links between Device E and each member device.

· Disable the spanning tree feature on the ports used for BFD MAD, because the two features conflict with each other.

Figure 15 Network diagram

Configuration procedure

1. Configure Device A:

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 1/1/1 and FortyGigE 1/1/2 to IRF-port 1/1.

[Sysname] irf-port 1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/2

[Sysname-irf-port1/1] quit

# Bind FortyGigE 1/1/3 and FortyGigE 1/1/4 to IRF-port 1/2.

[Sysname] irf-port 1/2

[Sysname-irf-port1/2] port group interface fortygige 1/1/3

[Sysname-irf-port1/2] port group interface fortygige 1/1/4

[Sysname-irf-port1/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

2. Configure Device B:

# Change the member ID of Device B to 2 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 2

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device B to Device A as shown in Figure 15, and log in to Device B.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 2/1/1 and FortyGigE 2/1/2 to IRF-port 2/1.

[Sysname] irf-port 2/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/2

[Sysname-irf-port2/1] quit

# Bind FortyGigE 2/1/3 and FortyGigE 2/1/4 to IRF-port 2/2.

[Sysname] irf-port 2/2

[Sysname-irf-port2/2] port group interface fortygige 2/1/3

[Sysname-irf-port2/2] port group interface fortygige 2/1/4

[Sysname-irf-port2/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

The two devices perform master election, and the one that has lost the election reboots to form an IRF fabric with the master.

3. Configure Device C:

# Change the member ID of Device C to 3 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 3

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device C to Device A as shown in Figure 15, and log in to Device C.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 3/1/1 and FortyGigE 3/1/2 to IRF-port 3/1.

[Sysname] irf-port 3/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/2

[Sysname-irf-port3/1] quit

# Bind FortyGigE 3/1/3 and FortyGigE 3/1/4 to IRF-port 3/2.

[Sysname] irf-port 3/2

[Sysname-irf-port3/2] port group interface fortygige 3/1/3

[Sysname-irf-port3/2] port group interface fortygige 3/1/4

[Sysname-irf-port3/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device C reboots to join the IRF fabric.

4. Configure Device D:

# Change the member ID of Device D to 4 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 4

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device D to Device B and Device C as shown in Figure 15, and log in to Device D.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 4/1/1 and FortyGigE 4/1/2 to IRF-port 4/1.

[Sysname] irf-port 4/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/2

[Sysname-irf-port4/1] quit

# Bind FortyGigE 4/1/3 and FortyGigE 4/1/4 to IRF-port 4/2.

[Sysname] irf-port 4/2

[Sysname-irf-port4/2] port group interface fortygige 4/1/3

[Sysname-irf-port4/2] port group interface fortygige 4/1/4

[Sysname-irf-port4/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device D reboots to join the IRF fabric. A four-chassis IRF fabric is formed.

5. Configure BFD MAD:

# Set the IRF link down report delay to 0 seconds.

<Sysname> system-view

[Sysname] irf link-delay 0

# Create VLAN 3, and add FortyGigE 1/1/5, FortyGigE 2/1/5, FortyGigE 3/1/5, and FortyGigE 4/1/5 to VLAN 3.

[Sysname] vlan 3

[Sysname-vlan3] port fortygige 1/1/5 fortygige 2/1/5 fortygige 3/1/5 fortygige 4/1/5

[Sysname-vlan3] quit

# Create VLAN-interface 3, and configure a MAD IP address for each member device on the VLAN interface.

[Sysname] interface vlan-interface 3

[Sysname-Vlan-interface3] mad bfd enable

[Sysname-Vlan-interface3] mad ip address 192.168.2.1 24 member 1

[Sysname-Vlan-interface3] mad ip address 192.168.2.2 24 member 2

[Sysname-Vlan-interface3] mad ip address 192.168.2.3 24 member 3

[Sysname-Vlan-interface3] mad ip address 192.168.2.4 24 member 4

[Sysname-Vlan-interface3] quit

# Disable the spanning tree feature on FortyGigE 1/1/5, FortyGigE 2/1/5, FortyGigE 3/1/5, and FortyGigE 4/1/5.

[Sysname] interface range fortygige 1/1/5 fortygige 2/1/5 fortygige 3/1/5 fortygige 4/1/5

[Sysname-if-range] undo stp enable

[Sysname-if-range] quit

6. Configure Device E as the intermediate device:

CAUTION:

If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection. False detection causes IRF split.

# Create VLAN 3.

<DeviceE> system-view

[DeviceE] vlan 3

# Assign FortyGigE 1/1/1 through FortyGigE 1/1/4 to the VLAN.

[DeviceE-vlan3] port fortygige 1/1/1 to fortygige 1/1/4

[DeviceE-vlan3] quit

ARP MAD-enabled IRF configuration example

Network requirements

As shown in Figure 16, set up a four-chassis IRF fabric at the distribution layer of the enterprise network.

· Configure ARP MAD for the IRF fabric and use Device E as an intermediate device. Device E can come from any vendor.

· To prevent loops, enable the spanning tree feature between the IRF fabric and Device E.

Figure 16 Network diagram

Configuration procedure

1. Configure Device A:

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 1/1/1 and FortyGigE 1/1/2 to IRF-port 1/1.

[Sysname] irf-port 1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/2

[Sysname-irf-port1/1] quit

# Bind FortyGigE 1/1/3 and FortyGigE 1/1/4 to IRF-port 1/2.

[Sysname] irf-port 1/2

[Sysname-irf-port1/2] port group interface fortygige 1/1/3

[Sysname-irf-port1/2] port group interface fortygige 1/1/4

[Sysname-irf-port1/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

2. Configure Device B:

# Change the member ID of Device B to 2 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 2

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device B to Device A as shown in Figure 16, and log in to Device B.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 2/1/1 and FortyGigE 2/1/2 to IRF-port 2/1.

[Sysname] irf-port 2/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/2

[Sysname-irf-port2/1] quit

# Bind FortyGigE 2/1/3 and FortyGigE 2/1/4 to IRF-port 2/2.

[Sysname] irf-port 2/2

[Sysname-irf-port2/2] port group interface fortygige 2/1/3

[Sysname-irf-port2/2] port group interface fortygige 2/1/4

[Sysname-irf-port2/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

The two devices perform master election, and the one that has lost the election reboots to form an IRF fabric with the master.

3. Configure Device C:

# Change the member ID of Device C to 3 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 3

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device C to Device A as shown in Figure 16, and log in to Device C.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 3/1/1 and FortyGigE 3/1/2 to IRF-port 3/1.

[Sysname] irf-port 3/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/2

[Sysname-irf-port3/1] quit

# Bind FortyGigE 3/1/3 and FortyGigE 3/1/4 to IRF-port 3/2.

[Sysname] irf-port 3/2

[Sysname-irf-port3/2] port group interface fortygige 3/1/3

[Sysname-irf-port3/2] port group interface fortygige 3/1/4

[Sysname-irf-port3/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device C reboots to join the IRF fabric.

4. Configure Device D:

# Change the member ID of Device D to 4 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 4

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device D to Device B and Device C as shown in Figure 16, and log in to Device D.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 4/1/1 and FortyGigE 4/1/2 to IRF-port 4/1.

[Sysname] irf-port 4/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/2

[Sysname-irf-port4/1] quit

# Bind FortyGigE 4/1/3 and FortyGigE 4/1/4 to IRF-port 4/2.

[Sysname] irf-port 4/2

[Sysname-irf-port4/2] port group interface fortygige 4/1/3

[Sysname-irf-port4/2] port group interface fortygige 4/1/4

[Sysname-irf-port4/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device D reboots to join the IRF fabric. A four-chassis IRF fabric is formed.

5. Configure ARP MAD on the IRF fabric:

# Enable the spanning tree feature globally, and map the ARP MAD VLAN to MSTI 1 in the MST region.

<Sysname> system-view

[Sysname] stp global enable

[Sysname] stp region-configuration

[Sysname-mst-region] region-name arpmad

[Sysname-mst-region] instance 1 vlan 3

[Sysname-mst-region] active region-configuration

[Sysname-mst-region] quit

# Configure the bridge MAC address of the IRF fabric to change as soon as the bridge MAC owner leaves.

[Sysname] undo irf mac-address persistent

# Set the domain ID of the IRF fabric to 1.

[Sysname] irf domain 1

# Create VLAN 3, and add FortyGigE 1/1/5, FortyGigE 2/1/5, FortyGigE 3/1/5, and FortyGigE 4/1/5 to VLAN 3.

[Sysname] vlan 3

[Sysname-vlan3] port fortygige 1/1/5 fortygige 2/1/5 fortygige 3/1/5 fortygige 4/1/5

[Sysname-vlan3] quit

# Create VLAN-interface 3, assign it an IP address, and enable ARP MAD on the interface.

[Sysname] interface vlan-interface 3

[Sysname-Vlan-interface3] ip address 192.168.2.1 24

[Sysname-Vlan-interface3] mad arp enable

You need to assign a domain ID (range: 0-4294967295)

[Current domain is: 1]:

The assigned domain ID is: 1

6. Configure Device E as the intermediate device:

CAUTION:

If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection. False detection causes IRF split.

# Enable the spanning tree feature globally, and map the ARP MAD VLAN to MSTI 1 in the MST region.

<DeviceE> system-view

[DeviceE] stp global enable

[DeviceE] stp region-configuration

[DeviceE-mst-region] region-name arpmad

[DeviceE-mst-region] instance 1 vlan 3

[DeviceE-mst-region] active region-configuration

[DeviceE-mst-region] quit

# Create VLAN 3, and add FortyGigE 1/1/1 through FortyGigE 1/1/4 to VLAN 3.

[DeviceE] vlan 3

[DeviceE-vlan3] port fortygige 1/1/1 to fortygige 1/1/4

[DeviceE-vlan3] quit

ND MAD-enabled IRF configuration example

Network requirements

As shown in Figure 17, set up a four-chassis IRF fabric at the distribution layer of the enterprise network.

· Configure ND MAD for the IRF fabric and use Device E as an intermediate device. Device E can come from any vendor.

· To prevent loops, enable the spanning tree feature between the IRF fabric and Device E.

Figure 17 Network diagram

Configuration procedure

1. Configure Device A:

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 1/1/1 and FortyGigE 1/1/2 to IRF-port 1/1.

[Sysname] irf-port 1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/1

[Sysname-irf-port1/1] port group interface fortygige 1/1/2

[Sysname-irf-port1/1] quit

# Bind FortyGigE 1/1/3 and FortyGigE 1/1/4 to IRF-port 1/2.

[Sysname] irf-port 1/2

[Sysname-irf-port1/2] port group interface fortygige 1/1/3

[Sysname-irf-port1/2] port group interface fortygige 1/1/4

[Sysname-irf-port1/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 1/1/1 to fortygige 1/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

2. Configure Device B:

# Change the member ID of Device B to 2 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 2

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device B to Device A as shown in Figure 17, and log in to Device B.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 2/1/1 and FortyGigE 2/1/2 to IRF-port 2/1.

[Sysname] irf-port 2/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/1

[Sysname-irf-port2/1] port group interface fortygige 2/1/2

[Sysname-irf-port2/1] quit

# Bind FortyGigE 2/1/3 and FortyGigE 2/1/4 to IRF-port 2/2.

[Sysname] irf-port 2/2

[Sysname-irf-port2/2] port group interface fortygige 2/1/3

[Sysname-irf-port2/2] port group interface fortygige 2/1/4

[Sysname-irf-port2/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 2/1/1 to fortygige 2/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

The two devices perform master election, and the one that has lost the election reboots to form an IRF fabric with the master.

3. Configure Device C:

# Change the member ID of Device C to 3 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 3

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device C to Device A as shown in Figure 17, and log in to Device C.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 3/1/1 and FortyGigE 3/1/2 to IRF-port 3/1.

[Sysname] irf-port 3/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/1

[Sysname-irf-port3/1] port group interface fortygige 3/1/2

[Sysname-irf-port3/1] quit

# Bind FortyGigE 3/1/3 and FortyGigE 3/1/4 to IRF-port 3/2.

[Sysname] irf-port 3/2

[Sysname-irf-port3/2] port group interface fortygige 3/1/3

[Sysname-irf-port3/2] port group interface fortygige 3/1/4

[Sysname-irf-port3/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 3/1/1 to fortygige 3/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device C reboots to join the IRF fabric.

4. Configure Device D:

# Change the member ID of Device D to 4 and reboot the device to validate the change.

<Sysname> system-view

[Sysname] irf member 1 renumber 4

Renumbering the member ID may result in configuration change or loss. Continue? [Y/N]:y

[Sysname] quit

<Sysname> reboot

# Connect Device D to Device B and Device C as shown in Figure 17, and log in to Device D.

# Shut down the physical interfaces used for IRF links.

<Sysname> system-view

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Bind FortyGigE 4/1/1 and FortyGigE 4/1/2 to IRF-port 4/1.

[Sysname] irf-port 4/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/1

[Sysname-irf-port4/1] port group interface fortygige 4/1/2

[Sysname-irf-port4/1] quit

# Bind FortyGigE 4/1/3 and FortyGigE 4/1/4 to IRF-port 4/2.

[Sysname] irf-port 4/2

[Sysname-irf-port4/2] port group interface fortygige 4/1/3

[Sysname-irf-port4/2] port group interface fortygige 4/1/4

[Sysname-irf-port4/2] quit

# Bring up the physical interfaces and save the configuration.

[Sysname] interface range fortygige 4/1/1 to fortygige 4/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] quit

[Sysname] save

# Activate the IRF port configuration.

[Sysname] irf-port-configuration active

Device D reboots to join the IRF fabric. A four-chassis IRF fabric is formed.

5. Configure ND MAD on the IRF fabric:

# Enable the spanning tree feature globally, and map the ND MAD VLAN to MSTI 1 in the MST region.

<Sysname> system-view

[Sysname] stp global enable

[Sysname] stp region-configuration

[Sysname-mst-region] region-name ndmad

[Sysname-mst-region] instance 1 vlan 3

[Sysname-mst-region] active region-configuration

[Sysname-mst-region] quit

# Configure the bridge MAC address of the IRF fabric to change as soon as the bridge MAC owner leaves.

[Sysname] undo irf mac-address persistent

# Set the domain ID of the IRF fabric to 1.

[Sysname] irf domain 1

# Create VLAN 3, and add FortyGigE 1/1/5, FortyGigE 2/1/5, FortyGigE 3/1/5, and FortyGigE 4/1/5 to VLAN 3.

[Sysname] vlan 3

[Sysname-vlan3] port fortygige 1/1/5 fortygige 2/1/5 fortygige 3/1/5 fortygige 4/1/5

[Sysname-vlan3] quit

# Create VLAN-interface 3, assign it an IP address, and enable ND MAD on the interface.

[Sysname] interface vlan-interface 3

[Sysname-Vlan-interface3] ipv6 address 2001::1 64

[Sysname-Vlan-interface3] mad nd enable

You need to assign a domain ID (range: 0-4294967295)

[Current domain is: 1]:

The assigned domain ID is: 1

6. Configure Device E as the intermediate device:

CAUTION:

If the intermediate device is also an IRF fabric, assign the two IRF fabrics different domain IDs for correct split detection. False detection causes IRF split.

# Enable the spanning tree feature globally, and map the ND MAD VLAN to MSTI 1 in the MST region.

<DeviceE> system-view

[DeviceE] stp global enable

[DeviceE] stp region-configuration

[DeviceE-mst-region] region-name ndmad

[DeviceE-mst-region] instance 1 vlan 3

[DeviceE-mst-region] active region-configuration

[DeviceE-mst-region] quit

# Create VLAN 3, and add FortyGigE 1/1/1 through FortyGigE 1/1/4 to VLAN 3.

[DeviceE] vlan 3

[DeviceE-vlan3] port fortygige 1/1/1 to fortygige 1/1/4

[DeviceE-vlan3] quit

Setting up an IRF 3 system

Overview

IRF 3 integrates multiple lower-layer devices with a higher-layer IRF fabric to provide high-density, low-cost connectivity at the access layer.

In an IRF 3 system, the higher-layer IRF fabric is called the parent fabric and the lower-layer devices are called port extenders (PEXs). You can manage and configure the PEXs from the parent fabric as if they were interface cards on the parent fabric.

Typically, IRF 3 works at the access layer of data centers. As shown in Figure 18, the access layer of a network is virtualized into an IRF 3 system. The system contains one parent fabric (a two-chassis IRF fabric) and multiple PEXs to provide connectivity for servers and hosts.

Figure 18 IRF 3 application scenario

IRF 3 provides the following benefits:

· Simplified topology—Devices in an IRF 3 system appear as one node. For redundancy and load balancing, a downstream or upstream device can connect to the IRF 3 system through multichassis link aggregation. Together with link aggregation, IRF 3 creates a loop-free Layer 2 network. The spanning tree feature is not needed among devices in the IRF 3 system or on the link aggregations. IRF 3 also simplifies the Layer 3 network topology because it reduces the number of routing peers. The network topology does not change when a device is added to or removed from the IRF 3 system.

· Single point of management—An IRF 3 system is accessible at a single IP address on the network. You can use this IP address to log in through any network port to manage all the devices in the system. For an SNMP NMS, an IRF 3 system is one managed network node.

· Network scalability and resiliency—You can increase the number of ports in an IRF 3 system by adding PEXs without changing network topology.

· High availability—Each PEX has multiple high-speed physical ports for uplink connectivity to the parent fabric. The links on these ports are aggregated and load balanced automatically.

· Decreased TCO—IRF 3 decreases hardware investments and management costs. In an IRF 3 system, the parent fabric performs all the management and routing functions, and the PEXs only forwards traffic. You can add low-performance devices as PEXs to an IRF 3 system for network scalability. In addition, PEXs can load software and synchronize configuration from the parent fabric without administrative intervention.

Basic concepts

IRF 3 includes IRF concepts and adds the concepts in this section. For more information about IRF concepts, see "Setting up an IRF fabric."

IRF 3 roles

The devices in an IRF 3 system have the following roles:

· Parent fabric—Higher-layer single-chassis or multichassis IRF fabric that controls the entire IRF 3 system, including PEXs. Each IRF 3 system has one parent fabric.

· Parent device—Member devices in the parent fabric.

· Master device—Controls and manages the entire IRF 3 system, including all parent devices and PEXs. The master device in the IRF fabric is also the master device for the IRF 3 system. You configure all devices (including PEXs and parent devices) from the master device.

· PEX—Operates as I/O modules of the parent fabric to receive and transmit traffic. All forwarding decisions are made on the parent fabric. Table 2 shows the operating states of PEXs.

Table 2 PEX operating states

State	Description
Loading	The PEX is starting up. To avoid problems, do not reboot a PEX while it is in Loading state.
Online	The PEX has started up and registered with the parent fabric.
Offline	The PEX is offline.

PEX port

A PEX port is a logical port created on the parent fabric for managing a PEX. For each PEX, you must create a unique PEX port, and assign all physical interfaces connected to the PEX to the PEX port.

PEX physical interface

PEX physical interfaces connect PEXs and the parent fabric.

You can set up multiple PEX links between the parent fabric and a PEX. These links aggregate automatically for backup and load balancing.

On the parent fabric, you must assign the PEX physical interfaces for one PEX to the same PEX port. On a PEX, you must connect all its PEX physical interfaces to the physical interfaces in the same PEX port.

Table 3 describes the states of PEX physical interfaces.

Table 3 PEX physical interface states

State	Description
Forwarding	The PEX physical interface is operating correctly and can forward data traffic.
Down	The physical link is disconnected. The PEX physical interface cannot forward any packets.
Blocked	The PEX physical interface cannot forward any packets except for IRF 3 packets. The Blocked state is a transitional state between Forwarding and Down. A PEX physical interface changes to the Blocked state in the following situations: · Incorrect physical connection: ? The PEX has PEX links to more than one PEX port on the parent fabric. ? The PEX port on the parent fabric contains physical links to more than one PEX. · The data link is forced to the Blocked state. In the startup phase, the PEX blocks a PEX physical interface if the interface's physical link is up, but it is not used for loading startup software. · The physical state of the interface is up, but the PEX link to the parent fabric has been disconnected. The PEX and the parent fabric cannot receive IRF 3 heartbeat packets from each other.

Virtual slot number

Each PEX is identified by a unique virtual slot number in an IRF 3 system.

After a PEX joins an IRF 3 system, the first segment in its interface numbers changes to the virtual slot number assigned to the PEX. For example, a PEX has an interface numbered 1/0/1 before it is added to an IRF 3 system. After it is added to an IRF 3 system as slot 100, the interface number changes to 100/0/1.

IRF 3 operating mechanisms

IRF 3 membership establishment

After you complete PEX configuration for a PEX, the master device monitors the PEX physical interfaces for the slot number request from the PEX. The PEX uses the following process to join the IRF 3 system:

1. Virtual slot assignment:

a. At startup, the PEX sends a slot number request to the master device.

b. The master device assigns the user-configured slot number to the PEX.

2. Software loading and PEX registration:

a. The PEX sends a startup software request to the master device.

b. The master device provides the correct Boot ROM and startup software images to the PEX.

c. The PEX loads the software images, and then automatically reboots to register with the master device.

3. Configuration synchronization:

a. The parent device issues its running configuration to the PEX.

b. The PEX runs with the configuration received from the master device instead of reading the configuration from its local startup configuration file.

4. PEX link maintenance:

The master device and the PEX send heartbeat packets on the PEX links to detect link failure. You can determine whether a PEX link is available by checking the state of its physical interfaces.

Configuration management

An IRF 3 system manages all its settings (including settings for PEXs) on the master device. You can configure and manage PEXs only from the master device. The running configuration on the master device has all settings in the IRF 3 system, including settings for PEXs. When a PEX reboots or is added, the master device issues its running configuration to the PEX.

Data forwarding

The PEXs do not have local forwarding capability.

The PEXs send any incoming traffic to the parent fabric. The parent fabric makes the forwarding decisions and sends the traffic to the outgoing interfaces. Figure 19 shows the data forwarding model.

Figure 19 Data forwarding model

IRF fabric split handling

When the parent fabric splits, a PEX uses the same conflict handling rules as LACP MAD and BFD MAD to select one split IRF fabric as its parent fabric. After selecting one IRF fabric as the parent fabric, the PEX blocks all PEX links to other IRF fabrics.

As a best practice, use LACP MAD or BFD MAD on the parent fabric to ensure that the PEX selects the same IRF fabric to forward traffic as IRF. If any other MAD mechanisms are used, the parent fabric selected by the PEX might be placed in Recovery state.

NOTE:

Ports on a PEX cannot be used for IRF MAD. When you configure MAD mechanisms, use ports on the parent fabric and devices that are not in the IRF 3 system.

Hardware compatibility

H3C S7500E-XS switches can only operate as parent devices. The switches support S5130-EI and S6300 PEXs.

Configuration restrictions and guidelines

For a successful IRF 3 system setup, read the configuration restrictions and guidelines carefully before you connect and set up a PEX.

PEX physical interface requirements

Make sure the PEX physical interfaces at the two ends of a PEX link are at the same rate.

Use Table 4 to identify physical interfaces for PEX links.

Table 4 Candidate PEX physical interfaces

Switch model	Candidate PEX physical interfaces	Remarks
S7500E-XS	Use the SFP+ or QSFP+ ports for PEX links.	N/A
S6300	Use the following physical interfaces for PEX links: · The highest numbered four SFP+ ports on the front panel. · QSFP+ ports on the front panel.	Do not use both SFP+ and QSFP+ ports for PEX links.
S5130-EI	Use SFP+ ports on the front panel for PEX links.	N/A

PEX physical interface shutdown restrictions on PEXs

The shutdown command cannot be executed on any ports of the PEXs for PEX links.

PEX cabling requirements

When you connect the parent fabric and PEXs, follow these cabling restrictions and guidelines:

· On the parent fabric, connect a PEX port's all physical interfaces to the same PEX.

· On a PEX, connect all its PEX physical interfaces to the physical interfaces in the same PEX port.

· Do not connect PEXs to each other.

· IRF 3 only supports one layer of PEXs. You cannot attach a lower-layer PEX to a higher-layer PEX.

· Do not attach a lower-layer network device to a PEX.

IRF member ID restrictions

In an IRF 3 system, change the member IDs of parent devices with caution. If the member ID of a parent device is changed, you must reconfigure the PEX port bindings on the parent device.

sFlow compatibility

sFlow is not available on PEX physical interfaces.

Cross-PEX link aggregation

Ports on PEXs of different switch series cannot be aggregated into one aggregation group.

Feature availability of PEXs

Some software features supported on the parent devices are not available for PEXs. For more information about these features, see the software release notes for the parent devices.

IRF 3 system setup and configuration task list

To set up and configure an IRF 3 system:

Tasks at a glance	Remarks
1. (Required.) Planning the IRF 3 system setup	N/A
2. (Optional.) Setting up the parent fabric	The parent fabric must be a single-chassis or multichassis IRF fabric.
3. Configuring IRF 3 settings on the parent fabric: a. (Optional.) Enabling IRF 3 capability b. (Required.) Creating PEX ports c. (Required.) Assigning virtual slot numbers to PEXs d. (Required.) Assigning physical interfaces to PEX ports e. (Optional.) Configuring PEX link load sharing mode f. (Required.) Specifying startup software images for PEXs	Specifying startup software images for PEXs is optional if the PEXs have storage media and can load PEX-capable startup software images locally. For more information about PEX software specification, see software upgrade in Fundamentals Configuration Guide.
4. (Required.) Connecting the PEXs to the parent fabric	Make sure the PEX cabling is consistent with the PEX physical interface assignment on the parent fabric. PEXs join the IRF 3 system when PEX links come up. To remove PEXs from the IRF 3 system, see "Removing PEXs from an IRF 3 system."

Planning the IRF 3 system setup

Consider the following items when you plan an IRF 3 system:

· Hardware compatibility and restrictions.

· Parent devices and PEXs.

· PEX physical interfaces and cabling scheme.

· Virtual slot assignment for PEXs.

The plan must meet the requirements described in "Hardware compatibility" and "Configuration restrictions and guidelines."

For more information about hardware and cabling, see the installation guide for the device.

Setting up the parent fabric

To set up an H3C S7500E-XS parent fabric, use the procedure described in "Setting up an IRF fabric."

Configuring IRF 3 settings on the parent fabric

Enabling IRF 3 capability

For a device to operate as a parent device, you must enable its IRF 3 capability by setting the IRF mode to enhanced. An IRF 3 system can contain a maximum of 2 S7500E-XS parent devices and a maximum of 30 PEXs.

To enable IRF 3 capability:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enable enhanced IRF mode.	irf mode enhanced	The default IRF mode is normal. IRF capability is enabled, and IRF 3 capability is disabled. To disable IRF 3 capability, use the following commands: · irf mode normal. · undo irf mode enhanced.
3. Return to user view.	quit	N/A
4. Save the running configuration.	save	N/A
5. Reboot the system for the setting to take effect.	reboot	N/A

Creating PEX ports

You must create a PEX port for each PEX.

To create a PEX port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Create a PEX port and enter PEX port view.	pex-port pex-id	By default, no PEX ports have been created. You can create a maximum of 120 PEX ports.
3. (Optional.) Configure a port description.	description text	The default PEX port description is pex-port pex-number, for example, pex-port 0002.

Assigning virtual slot numbers to PEXs

You must assign a unique virtual slot number to each PEX.

You cannot change the slot number of a PEX while it is starting up.

An operating PEX will reboot if you change or remove its slot number.

To assign a virtual slot number to a PEX:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter PEX port view.	pex-port pex-id	N/A
3. Assign a virtual slot number to the PEX.	associate slot-number	By default, a PEX is not assigned a virtual slot number.

Assigning physical interfaces to PEX ports

A PEX port must have a minimum of one physical interface in Forwarding state for its PEX to communicate with the parent fabric correctly. If a PEX port has only one physical interface in Forwarding state, the PEX will reboot when any of the following events occur:

· The interface is removed from the PEX port.

· The interface goes down.

For more information about physical interfaces that can be used for PEX links, see "PEX physical interface requirements."

To assign physical interfaces to a PEX port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter interface view or interface range view.	· Enter interface view: interface interface-type interface-number · Enter interface range view: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24>	To configure one interface, enter interface view. To configure a range of interfaces, enter interface range view.
3. Shut down the physical interface or interfaces.	shutdown	By default, all physical interfaces are up.
4. Return to system view.	quit	N/A
5. Enter PEX port view.	pex-port pex-id	N/A
6. Assign a physical interface to the PEX port.	port group interface interface-type interface-number	By default, a PEX port does not contain physical interfaces. Repeat this step to assign multiple physical interfaces to the PEX port. A physical interface's configuration is automatically restored to the default after you assign the interface to a PEX port. Each PEX port can have a maximum of six physical interfaces.
7. Return to system view.	quit	N/A
8. Enter interface view or interface range view.	· Enter interface view: interface interface-type interface-number · Enter interface range view: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24>	N/A
9. Bring up the physical interface or interfaces.	undo shutdown	N/A

Configuring PEX link load sharing mode

IMPORTANT:

Before you configure the PEX link load sharing mode for a PEX port, make sure you have bound a minimum of one physical interface to the PEX port.

On a PEX port, traffic is balanced across its physical links.

You can configure the PEX port to distribute traffic based on any combination of the following criteria:

· Source IP address.

· Source MAC address.

· Destination IP address.

· Destination MAC address.

· Ingress port.

The system displays an error message if a criteria combination is not supported.

To configure the PEX link load sharing mode for a PEX port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter PEX port view.	pex-port pex-id	N/A
3. Configure the PEX link load sharing mode.	pex-port load-sharing mode { destination-ip \| destination-mac \| ingress-port \| source-ip \| source-mac } *	The following are the default load sharing mode: · Non-IP traffic—Source and destination MAC addresses. · Non-TCP/-UDP IP traffic—Source and destination IP addresses. · TCP/UDP IP traffic—Source and destination service ports. If you execute this command multiple times, the most recent configuration takes effect.

Connecting the PEXs to the parent fabric

Connect all the PEX physical interfaces to the physical interfaces assigned to the same PEX port on the parent fabric.

For more information about connection restrictions and guidelines, see "PEX cabling requirements."

Removing PEXs from an IRF 3 system

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Change PEXs to switch mode.	pex working-mode switch { all \| slot slot-number1 [ to slot-number2 ] }	PEXs operate in PEX mode in the IRF 3 system. The switch mode change will take effect at reboot. To cancel the change, configure the undo pex working-mode switch { all \| slot slot-number1 [ to slot-number2 ] } command before the reboot. In switch mode, PEXs operate independently from the parent fabric and cannot be managed from the parent fabric.
3. Return to user view.	quit	N/A
4. Reboot each PEX that is placed in switch mode.	reboot slot slot-number	Repeat this step to reboot all PEXs that are placed in switch mode. The devices will be removed from the IRF 3 system and operate as independent switches. IMPORTANT: After the removed devices reboot, the mode change is included in their running configuration but not in their startup configuration files. To prevent the original mode from being restored when another reboot occurs, you must save the configuration on each removed device.
5. Enter system view.	system-view	N/A
6. Enter interface view or interface range view.	· Enter interface view: interface interface-type interface-number · Enter interface range view: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24>	Specify all physical interfaces that are connected to the removed PEXs.
7. Shut down the physical interfaces.	shutdown	By default, all physical interfaces are up.
8. Return to system view.	quit	N/A
9. Remove the PEX settings for a removed PEX.	a Enter PEX port view. pex-port pex-id b Remove each physical interface from the PEX port. undo port group interface interface-type interface-number c Return to system view. quit d Remove the PEX port. undo pex-port pex-id	Repeat this step to remove the PEX settings for each removed PEX.
10. Enter interface view or interface range view.	· Enter interface view: interface interface-type interface-number · Enter interface range view: interface range { interface-type interface-number [ to interface-type interface-number ] } &<1-24>	N/A
11. Bring up the physical interfaces.	undo shutdown	N/A

Displaying and maintaining PEXs

Execute display commands in any view.

Task	Command
Display PEX port information.	display pex-port [ pex-id ] [ verbose ]
Display the operating mode settings for PEXs in the IRF 3 system.	display pex working-mode { all \| slot slot-number1 [ to slot-number2 ] }
Display the PEX startup software images stored on the parent fabric.	display boot-loader pex [ pex-model ]

For more information about the display boot-loader pex command, see Fundamentals Command Reference.

IRF 3 system configuration example

Network requirements

As shown in Figure 20, set up an IRF 3 system that contains a two-chassis H3C S7500E-XS parent fabric and two S6300-52QF PEXs.

Figure 20 Network diagram

Configuration procedure

IMPORTANT:

Make sure the switches to be used as PEXs run PEX-capable Boot ROM and Comware images. For software versions that support PEX, see the release notes for the switches.

Configuring the parent fabric

# Set up a two-chassis IRF fabric, as described in "Setting up an IRF fabric." (Details not shown.)

# Enable enhanced IRF mode on the IRF fabric.

<Sysname> system-view

[Sysname] irf mode enhanced

[Sysname] quit

<Sysname> reboot

# Create PEX port 1 for PEX 1.

<Sysname> system-view

[Sysname] pex-port 1

# Assign virtual slot number 100 to PEX 1.

[Sysname-pex-port1] associate 100

[Sysname-pex-port1] quit

# Shut down the ports Ten-GigabitEthernet 1/1/1 through Ten-GigabitEthernet 1/1/4 and Ten-GigabitEthernet 2/1/1 through Ten-GigabitEthernet 2/1/4.

[Sysname] interface range ten-gigabitethernet 1/1/1 to ten-gigabitethernet 1/1/4 ten-gigabitethernet 2/1/1 to ten-gigabitethernet 2/1/4

[Sysname-if-range] shutdown

[Sysname-if-range] quit

# Assign Ten-GigabitEthernet 1/1/1 and Ten-GigabitEthernet 2/1/1 to PEX port 1.

[Sysname] pex-port 1

[Sysname-pex-port1] port group interface ten-gigabitethernet 1/1/1

[Sysname-pex-port1] port group interface ten-gigabitethernet 2/1/1

# Configure the description of PEX port 1 as connect-to-pex1.

[Sysname-pex-port1] description connect-to-pex1

[Sysname-pex-port1] quit

# Create PEX port 2 for PEX 2.

[Sysname] pex-port 2

# Assign virtual slot number 101 to PEX 2.

[Sysname-pex-port2] associate 101

# Assign Ten-GigabitEthernet 1/1/2 and Ten-GigabitEthernet 2/1/2 to PEX port 2.

[Sysname-pex-port2] port group interface ten-gigabitethernet 1/1/2

[Sysname-pex-port2] port group interface ten-gigabitethernet 2/1/2

# Configure the description of PEX port 2 as connect-to-pex2.

[Sysname-pex-port2] description connect-to-pex2

[Sysname-pex-port2] quit

# Bind all other physical interfaces in the same group as the PEX physical interfaces to PEX port 1 and PEX port 2.

[Sysname] pex-port 1

[Sysname-pex-port1] port group interface ten-gigabitethernet 1/1/3

[Sysname-pex-port1] port group interface ten-gigabitethernet 1/1/4

[Sysname-pex-port1] quit

[Sysname] pex-port 2

[Sysname-pex-port2] port group interface ten-gigabitethernet 2/1/3

[Sysname-pex-port2] port group interface ten-gigabitethernet 2/1/4

[Sysname-pex-port2] quit

# Bring up the ports Ten-GigabitEthernet 1/1/1 through Ten-GigabitEthernet 1/1/4 and Ten-GigabitEthernet 2/1/1 through Ten-GigabitEthernet 2/1/4.

[Sysname] interface range ten-gigabitethernet 1/1/1 to ten-gigabitethernet 1/1/4 ten-gigabitethernet 2/1/1 to ten-gigabitethernet 2/1/4

[Sysname-if-range] undo shutdown

[Sysname-if-range] return

# Save the configuration.

<Sysname> save

The current configuration will be written to the device. Are you sure? [Y/N]:y

Please input the file name(*.cfg)[flash:/startup.cfg]

(To leave the existing filename unchanged, press the enter key):

flash:/startup.cfg exists, overwrite? [Y/N]:y

Validating file. Please wait...

Saved the current configuration to mainboard device successfully.

# Use FTP or TFTP to transfer PEX startup software image file to the parent device. (Details not shown.)

NOTE:

You must store the image file in the root directory of the flash memory on the master device.

# Specify the file as the startup image file for S6300-52QF switches.

<Sysname> boot-loader pex PEX-S6300 file ipe flash:/S6300PEX.ipe main

Verifying the IPE file and the images....Done.

Decompressing file S6300PEX-CMW710-BOOT-A0045P57.bin to flash:/S6300PEX-CMW710-BOOT-A0045P57.bin.....................Done.

Decompressing file S6300PEX-CMW710-SYSTEM-A0045P57.bin to flash:/S6300PEX-CMW710-SYSTEM-A0045P57.bin............................................................................................................Done.

The system reads the images from the file after they pass verification.

Connecting the PEXs to the parent fabric

# Connect the PEXs to the parent fabric, as shown in Figure 20. (Details not shown.)

Configuring the PEXs

1. Change the operating mode to PEX from the Boot menu or CLI:

? Change the operating mode to PEX from the Boot menu:

# Reboot PEX 1 and press Ctrl+B at the prompt. If you have set a Boot menu password, you must enter the correct password to access the Boot menu.

Starting......

Press Ctrl+D to access BASIC BOOT MENU

******************************************************************************

* *

* H3C S6300-52QF BOOTROM, Version 150 *

* *

******************************************************************************

Creation Date : Jan 12 2016,19:17:00

CPU Clock Speed : 1000MHz

Memory Size : 2048MB

Flash Size : 512MB

CPLD Version : 002/002

PCB Version : Ver.B

Mac Address : 70F96D3DBB2B

PEX mode is disabled.

Press Ctrl+B to access EXTENDED BOOT MENU...0

Password recovery capability is enabled.

# In the Boot menu, press Ctrl+Y to change the operating mode to PEX.

EXTENDED BOOT MENU

1. Download image to flash

2. Select image to boot

3. Display all files in flash

4. Delete file from flash

5. Restore to factory default configuration

6. Enter BootRom upgrade menu

7. Skip current system configuration

8. Set switch startup mode

0. Reboot

Ctrl+Z: Access EXTENDED ASSISTANT MENU

Ctrl+F: Format file system

Ctrl+P: Change authentication for console login

Ctrl+Y: Change Work Mode

Ctrl+R: Download image to SDRAM and run

Enter your choice(0-8):

# Enter Y to confirm the operating mode change.

PEX mode is disabled. Are you sure you want to enable PEX mode? [Y/N]Y

Mode changed successfully

# Enter 0 in the Boot menu to reboot PEX 1.

? Change the operating mode to PEX from the CLI:

# Enter system view.

<Sysname> system-view

# Change the operating mode to PEX.

[Sysname] pex working-mode pex slot 1

Are you sure you want to change to the PEX mode? [Y/N]: y

If you want to change parent device to PEX mode or change PEX device to switch mode, you must reboot the device.

Reboot PEX 1 for the change to take effect.

At startup, PEX 1 loads the startup images from the parent fabric.

******************************************************************************

* *

* H3C S6300-52QF BOOTROM, Version 150 *

* *

******************************************************************************

Creation Date : Jan 12 2016,19:17:00

CPU Clock Speed : 1000MHz

Memory Size : 2048MB

Flash Size : 512MB

CPLD Version : 002/002

PCB Version : Ver.B

Mac Address : 70BAEF5CA028

PEX mode is enabled.

Press Ctrl+B to access EXTENDED BOOT MENU...0

Loading the main image files...

Loading file flash:/s5800v2_s6300pex-cmw710-system-e2130l15.bin..........................................................................................................................................................................................................................................................................Done.

Loading file flash:/s5800v2_s6300pex-cmw710-boot-e2130l15.bin........................................................................Done.

Image file flash:/s5800v2_s6300pex-cmw710-boot-e2130l15.bin is

self-decompressing...........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Done.

System is starting...

Started downloading S6300PEX-CMW710-SYSTEM-A0045P57.bin

........................................................................................................................Done

Writing to flash

........................................................................................................................................................................................................................................................................................Done

Started downloading S6300PEX-CMW710-BOOT-A0045P57.bin

........................................................................................................................Done

Writing to flash

................................................................Done

Starting......

Press Ctrl+D to access BASIC BOOT MENU

********************************************************************************

* *

* H3C S6300-52QF BOOTROM, Version 150 *

* *

********************************************************************************

Creation Date : Jan 12 2016,19:17:00

CPU Clock Speed : 1000MHz

Memory Size : 2048MB

Flash Size : 512MB

CPLD Version : 002/002

PCB Version : Ver.B

Mac Address : 70BAEF5CA028

PEX mode is enabled.

Press Ctrl+B to access EXTENDED BOOT MENU...0

Loading the main image files...

Loading file flash:/S6300PEX-CMW710-SYSTEM-A0045P57.bin..................................................................................................................................................................................................................................................................................Done.

Loading file flash:/S6300PEX-CMW710-BOOT-A0045P57.bin..............................................................................Done.

Image file flash:/S6300PEX-CMW710-BOOT-A0045P57.bin is self-decompressing.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Done.

System is starting...

Cryptographic algorithms tests passed.

Done.

While the PEX is starting up, the parent fabric displays messages about PEX port state changes, PEX registration, and PEX startup.

%Jan 12 10:32:43:326 2016 H3C PEX/4/PEX_LINK_BLOCK: -Slot=1; Status of Ten-GigabitEthernet1/1/1 changed from down to blocked.

%Jan 12 10:32:43:326 2016 H3C PEX/4/PEX_LINK_BLOCK: -Slot=2; Status of Ten-GigabitEthernet2/1/1 changed from down to blocked.

%Jan 12 10:32:43:352 2016 H3C IFNET/3/PHY_UPDOWN: Ten-GigabitEthernet1/1/1 link status is up.

%Jan 12 10:32:43:352 2016 H3C IFNET/3/PHY_UPDOWN: Ten-GigabitEthernet2/1/1 link status is up.

%Jan 12 10:32:43:353 2016 H3C IFNET/5/LINK_UPDOWN: Line protocol on the interface Ten-GigabitEthernet1/1/1 is up.

%Jan 12 10:32:43:353 2016 H3C IFNET/5/LINK_UPDOWN: Line protocol on the interface Ten-GigabitEthernet2/1/1 is up.

%Jan 12 10:32:52:753 2016 H3C PEX/5/PEX_REG_REQUEST: Received a REGISTER request on PEX port 1 from PEX (slot 100).

%Jan 12 10:32:52:766 2016 H3C DEV/4/BOARD_LOADING: Board in slot 100 is loading software images.

%Jan 12 10:32:52:742 2016 H3C PEX/5/PEX_LINK_FORWARD: -Slot=1; Status of Ten-GigabitEthernet1/1/1 changed from blocked to forwarding.

%Jan 12 10:32:52:742 2016 H3C PEX/5/PEX_LINK_FORWARD: -Slot=2; Status of Ten-GigabitEthernet2/1/1 changed from blocked to forwarding.

%Jan 12 10:33:09:127 2016 H3C DEV/2/BOARD_STATE_FAULT: Board state changed to Fault on slot 100, type is unknown.

%Jan 12 10:33:21:290 2016 H3C DEV/5/BOARD_STATE_NORMAL: Board state changed to Normal on slot 100, type is S6300-52QF.

%Jan 12 10:33:27:754 2016 H3C PEX/5/PEX_REG_JOININ: PEX (slot 100) registered successfully on PEX port 1.

%Jan 12 10:33:28:645 2016 H3C IFNET/3/PHY_UPDOWN: Pex100/0/51 link status is up.

%Jan 12 10:33:28:645 2016 H3C IFNET/3/PHY_UPDOWN: Pex100/0/52 link status is up.

%Jan 12 10:33:28:647 2016 H3C IFNET/5/LINK_UPDOWN: Line protocol on the interface Pex100/0/51 is up.

%Jan 12 10:33:28:647 2016 H3C IFNET/5/LINK_UPDOWN: Line protocol on the interface Pex100/0/52 is up.

2. Configure PEX 2 in the same way PEX 1 is configured. (Details not shown.)

Verifying the configuration

# Verify that the IRF 3 system has been set up. You can configure the PEXs from the parent fabric if the PEXs are in Online state and each have a minimum of one PEX link in Forwarding state.

<Sysname> display pex-port verbose

PEX port 1:

Description: connect-to-pex1

Associated slot numbers: 1

Slot PEX status

*100 Online

Member interfaces: 4

Member interface Status Peer interface

XGE1/1/1 Forwarding PEX100/0/51

XGE1/1/3 Down --

XGE1/1/4 Down --

XGE2/1/1 Forwarding PEX100/0/52

PEX port 2:

Description: connect-to-pex2

Associated slot numbers: 1

Slot PEX status

*101 Online

Member interfaces: 4

Member interface Status Peer interface

XGE1/1/2 Forwarding PEX101/0/52

XGE2/1/2 Forwarding PEX101/0/51

XGE2/1/3 Down --

XGE2/1/4 Down --

02-Virtual Technologies Configuration Guide

Basic concepts

IRF member roles

IRF member ID

IRF port

IRF physical interface

MAD

IRF domain ID

IRF split

IRF merge

Member priority

Detection

Failure recovery

Candidate IRF physical interfaces

Selecting transceiver modules and cables

ECMP

IRF mode

System operating mode

Configuring a member device description

Specifying a MAC address as the IRF bridge MAC address

Configuring BFD MAD that uses common Ethernet ports

Configuring BFD MAD that uses management Ethernet ports

Configuring ARP MAD that uses common Ethernet ports

Configuring ARP MAD that uses management Ethernet ports

Configuration restrictions and guidelines

Configuration procedure

Removing an expansion interface card that has IRF physical interfaces

Displaying and maintaining an IRF fabric

Network requirements

Configuration procedure

Network requirements

Configuration procedure

Network requirements

Configuration procedure

Network requirements

Configuration procedure

IRF 3 roles

PEX port

PEX physical interface

Virtual slot number

IRF 3 membership establishment

Configuration management

Data forwarding

PEX physical interface requirements

PEX cabling requirements

Displaying and maintaining PEXs

Configuring the parent fabric

Connecting the PEXs to the parent fabric

Configuring the PEXs

Intelligent Terminal Products

Product Support Services

Technical Service Solutions

Resource Center

Policy

Online Help

Become a Partner

Partner Policy & Program

Global Learning

Partner Sales Resources