In an Ethernet network, an MA serves the specified VLAN or no VLAN. An MA that serves a VLAN is considered to be carrying VLAN attribute. An MA that serves no VLAN is considered to be carrying no VLAN attribute.

In an MPLS Layer 2 VPN, an MA can only serve the specified cross-connect.

Maintenance point

An MP is configured on a port and belongs to an MA. MPs include the following types: maintenance association end points (MEPs) and maintenance association intermediate points (MIPs).

MEPs define the boundary of the MA. Each MEP is identified by a MEP ID.

In an Ethernet network, the MA to which a MEP belongs defines the VLAN of packets sent by the MEP.

In an MPLS Layer 2 VPN, the MA to which a MEP belongs defines the cross-connect of packets sent by the MEP.

MEPs include inward-facing MEPs and outward-facing MEPs:

· An inward-facing MEP does not send packets to its host port. Rather, it sends packets to other ports on the device. In an Ethernet network, the packets are broadcasted in the VLAN that the MA of the MEP serves. In an MPLS Layer 2 VPN, the packets are broadcast in the VLAN that the MA of the MEP serves.

· An outward-facing MEP sends packets to its host port.

A MIP is internal to an MA. It cannot send CFD packets actively, but it can handle and respond to CFD packets. MIPs are automatically created by the device. By cooperating with MEPs, a MIP can perform a function similar to ping and traceroute.

The MA to which a MIP belongs defines the VLAN of packets that the MIP can receive.

The MIP-related configuration takes effect only in Ethernet networks.

MEP list

A MEP list is a collection of local MEPs allowed to be configured and the remote MEPs to be monitored in the same MA. It lists all the MEPs configured on different devices in the same MA. The MEPs all have unique MEP IDs. When a MEP receives from a remote device a continuity check message (CCM) carrying a MEP ID not in the MEP list of the MA, it drops the message.

The local device must send CCM messages carrying the Remote Defect Indication (RDI) flag bits. Otherwise, the peer device cannot sense certain failures. When a local MEP has not learned all remote MEPs in the MEP list, the MEPs in the MA might not carry the RDI flag bits in CCMs.

CFD levels

MD levels

To accurately locate faults, CFD introduces eight levels (from 0 to 7) to MDs. The bigger the number, the higher the level and the larger the area covered. Domains can touch or nest (if the outer domain has a higher level than the nested one) but cannot intersect or overlap.

MD levels facilitate fault location and make fault location more accurate. As shown in Figure 1, MD_A in light blue nests MD_B in dark blue. If a connectivity fault is detected at the boundary of MD_A, any of the devices in MD_A, including Device A through Device E, might fail. If a connectivity fault is also detected at the boundary of MD_B, the failure points can be any of Device B through Device D. If the devices in MD_B can operate correctly, at least Device C is operational.

NOTE:

This section assumes that physical links between devices are in good condition.

Figure 1 Two nested MDs

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CFD exchanges messages and performs operations on a per-domain basis. By planning MDs correctly in a network, you can use CFD to rapidly locate failure points.

MA and MP levels

The level of an MA equals the level of the MD to which the MA belongs.

The level of a MEP equals the level of the MD to which the MEP belongs.

The level of a MIP is defined by its generation rule and the MD to which the MIP belongs. MIPs are generated on each port automatically according to the following MIP generation rules:

· Default rule—If no lower-level MIP exists on an interface, a MIP is created on the current level. A MIP can be created even if no MEP is configured on the interface.

· Explicit rule—If no lower-level MIP exists and a lower-level MEP exists on an interface, a MIP is created on the current level. A MIP can be created only when a lower-level MEP is created on the interface.

If a port has no MIP, the system will check the MAs in each MD (from low to high levels), and follow the procedure as described in Figure 2 to create or not to create MIPs at the current level.

Figure 2 Procedure of creating MIPs

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CFD grading example

Figure 3 demonstrates a grading example of the CFD module. Four levels of MDs (0, 2, 3, and 5) are designed. The bigger the number, the higher the level and the larger the area covered. MPs are configured on the ports of Device A through Device F. Port A of Device B is configured with the following MPs:

· A level 5 MIP.

· A level 3 inward-facing MEP.

· A level 2 inward-facing MEP.

· A level 0 outward-facing MEP.

Figure 3 CFD grading example

Packet processing of MPs

For an MA carrying VLAN attribute, MPs of the MA send packets only in the VLAN that the MA serves. The level of packets sent by an MP equals the level of the MD to which the MP belongs.

For an MA not carrying VLAN attribute, MPs of the MA can only be outward-facing MEPs. The level of packets sent by an outward-facing MEP equals the level of the MD to which the MEP belongs.

A MEP forwards packets at a higher level without any processing and only processes packets of its level or lower.

A MIP forwards packets of a different level without any processing and only processes packets of its level.

CFD functions

CFD functions, which are implemented through the MPs, include:

· Continuity check (CC).

· Loopback (LB).

· Linktrace (LT).

· Alarm indication signal (AIS).

· Loss measurement (LM).

· Delay measurement (DM).

· Test (TST).

Continuity check

Connectivity faults are usually caused by device faults or configuration errors. Continuity check examines the connectivity between MEPs. This function is implemented through periodic sending of CCMs by the MEPs. A CCM sent by one MEP is intended to be received by all the other MEPs in the same MA. If a MEP fails to receive the CCMs within 3.5 times the sending interval, the link is considered as faulty and a log is generated. When multiple MEPs send CCMs at the same time, the multipoint-to-multipoint link check is achieved. CCM frames are multicast frames.

Loopback

Similar to ping at the IP layer, loopback verifies the connectivity between a source device and a target device. To implement this function, the source MEP sends loopback messages (LBMs) to the target MP. Depending on whether the source MEP can receive a loopback reply message (LBR) from the target MEP, the link state between the two can be verified.

LBM frames are multicast and unicast frames. The device can send and receive unicast LBM frames, and can receive multicast LBM frames but cannot send multicast LBM frames. LBR frames are unicast frames.

Linktrace

Linktrace is similar to traceroute. It identifies the path between the source MEP and the target MP. The source MEP sends the linktrace messages (LTMs) to the target MP. After receiving the messages, the target MP and the MIPs that the LTM frames pass send back linktrace reply messages (LTRs) to the source MEP. Based on the reply messages, the source MEP can identify the path to the target MP. LTM frames are multicast frames and LTRs are unicast frames.

AIS

The AIS function suppresses the number of error alarms reported by MEPs. If a local MEP does not receive any CCM frames from its peer MEP within 3.5 times the CCM transmission interval, it immediately starts sending AIS frames. The AIS frames are sent periodically in the opposite direction of CCM frames. When the peer MEP receives the AIS frames, it suppresses the error alarms locally, and continues to send the AIS frames. If the local MEP receives CCM frames within 3.5 times the CCM transmission interval, it stops sending AIS frames and restores the error alarm function. AIS frames are multicast frames.

LM

The loss measurement (LM) function measures the frame loss between a pair of MEPs, including the following types:

· One-way LM—The source MEP sends loss measurement messages (LMMs) to the target MEP. The target MEP responds with loss measurement replies (LMRs). The source MEP calculates the number of lost frames according to the counter values of the two consecutive LMRs (the current LMR and the previous LMR). LMMs and LMRs are unicast frames.

The one-way LM function can be implemented in one of the following ways:

¡ Short-period LM—The source MEP sends a configurable number of LMMs at a configurable interval. The test result is printed when the test ends.

¡ Continual LM—The source MEP continually sends LMMs at a configurable interval until continual LM is administratively disabled. To view the test result, use the display cfd slm history command on the target MEP.

Continual LM can work with port collaboration. Port collaboration shuts down or blocks a port based on the continual LM result. For more information about port collaboration, see "Port collaboration."

DM

The DM function measures frame delays between two MEPs, including the following types:

· One-way frame delay measurement

The source MEP sends a one-way delay measurement (1DM) frame, which carries the transmission time, to the target MEP. When the target MEP receives the 1DM frame, it does the following:

¡ Records the reception time.

¡ Calculates and records the link transmission delay and jitter (delay variation) according to the transmission time and reception time.

1DM frames are unicast frames.

The one-way DM function can be implemented in one of the following ways:

¡ Short-period DM—The source MEP sends a configurable number of 1DM frames at a configurable interval. To view the test result, use the display cfd dm one-way history command on the target MEP.

¡ Continual DM—The source MEP continually sends 1DM frames at a configurable interval until continual DM is administratively disabled. To view the test result, use the display cfd dm one-way history command on the target MEP.

· Two-way frame delay measurement

The source MEP sends a delay measurement message (DMM), which carries the transmission time, to the target MEP. When the target MEP receives the DMM, it responds with a delay measurement reply (DMR). The DMR carries the reception time and transmission time of the DMM and the transmission time of the DMR. When the source MEP receives the DMR, it does the following:

¡ Records the DMR reception time.

¡ Calculates the link transmission delay and jitter according to the DMR reception time and DMM transmission time.

DMM frames and DMR frames are unicast frames.

The two-way DM function can be implemented in one of the following ways:

¡ Short-period two-way DM—The source MEP sends a configurable number of DMMs at a configurable interval.

¡ Continual two-way DM—The source MEP continually sends DMMs at a configurable interval until continual two-way DM is administratively disabled. To view the test result, use the display cfd dm two-way history command on the target MEP.

Continual two-way DM can work with port collaboration. Port collaboration shuts down or blocks a port based on the continual two-way DM result. For more information about port collaboration, see "Port collaboration."

TST

The TST function tests the bit errors between two MEPs. The source MEP sends a TST frame, which carries the test pattern, such as pseudo random bit sequence (PRBS) or all-zero, to the target MEP. When the target MEP receives the TST frame, it determines the bit errors by calculating and comparing the content of the TST frame. TST frames are unicast frames.

This function can be implemented in one of the following ways:

· Short-period TST—The source MEP sends a configurable number of TST frames at a configurable interval.

· Continual TST—The source MEP continually sends TST frames at a configurable interval until continual TST is administratively disabled. To view the test result, use the display cfd tst history command on the target MEP.

Continual TST can work with port collaboration. Port collaboration shuts down or blocks a port based on the continual TST result. For more information about port collaboration, see "Port collaboration."

Threshold alarm

The threshold alarm function monitors the transmission performance of links. The system generates an alarm when the transmission performance metric of a link crosses the specified upper limit or lower limit three times in succession.

Port collaboration

Port collaboration shuts down or blocks ports based on the result of link detection performed by outward-facing MEPs.

Triggering events

Port collaboration can be triggered by the following events:

· Continuity check expires.

· The link transmission delay in continual two-way DM reaches or exceeds the upper limit, or reaches or falls below the lower limit.

· The CCMs with the RDI flag bit set are received.

· The packet loss ratio in continual LM reaches or exceeds the upper limit, or reaches or falls below the lower limit.

· The bit error ratio in continual TST reaches or exceeds the upper limit, or reaches or falls below the lower limit.

You can specify both triggering events for an interface. Both triggering events can take effect.

Triggered actions

Port collaboration takes one of the following triggered actions:

· Blocks the port by changing its link layer protocol state to DOWN (CFD). The port cannot send or receive any data packets.

· Shuts down the port by changing its physical state to CFD DOWN. The port cannot send or receive any data packets or protocol packets.

Link recovery

If a port is blocked by CFD, it can automatically come up when the link recovers, except that the block action is triggered by continual LM. To bring up the port blocked in continual LM, execute the undo cfd port-trigger slm action or cfd slm port-trigger up-delay command.

If a port is shut down by CFD, it cannot automatically come up when the link recovers. To bring up the port, you must execute the undo shutdown or undo cfd port-trigger command.

Collaboration between CFD and Track

CFD can collaborate with Track as follows:

· If CFD detects that the peer is reachable, it notifies the Track module. The track module sets the state of the track entry to Positive.

· If CFD detects that the peer is unreachable, it notifies the Track module. The track module sets the state of the track entry to Negative.

For more information about Track, see "Configuring Track."

Protocols and standards

· IEEE 802.1ag, Virtual Bridged Local Area Networks Amendment 5: Connectivity Fault Management

· ITU-T Y.1731, OAM functions and mechanisms for Ethernet based networks

Restrictions and guidelines: CFD configuration

When you configure CFD, follow these restrictions and guidelines:

· Configure CC before you use the MEP ID of the remote MEP to configure other CFD functions. This restriction does not apply when you use the MAC address of the remote MEP to configure other CFD functions.

· Typically, a port blocked by the spanning tree feature cannot receive or send CFD messages except in the following cases:

¡ The port is configured as an outward-facing MEP.

¡ The port is configured as a MIP or inward-facing MEP, which can still receive and send CFD messages except CCM messages.

For more information about the spanning tree feature, see Layer 2—LAN Switching Configuration Guide.

CFD tasks at a glance

To configure CFD, perform the following tasks:

1. Configuring basic CFD settings

a. Enabling CFD

b. Configuring service instances

c. Configuring MEPs

d. Configuring MIP auto-generation rules

2. Configuring CFD functions

a. Configuring CC

b. (Optional.) Configuring LB

c. (Optional.) Configuring LT

d. (Optional.) Configuring AIS

e. (Optional.) Configuring one-way LM

f. (Optional.) Configuring one-way DM

g. (Optional.) Configuring two-way DM

h. (Optional.) Configuring TST

i. (Optional.) Configuring threshold alarm

3. (Optional.) Configuring port collaboration

Prerequisites for CFD

For CFD to work correctly, design the network by performing the following tasks:

· Grade the MDs in the entire network, and define the boundary of each MD.

· Assign a name for each MD. Make sure the devices in the same MD use the same MD name.

· Define the MA in each MD according to the VLAN or cross-connect you want to monitor.

· Assign a name for each MA. Make sure that the devices in the same MA in the same MD use the same MA name.

· Determine the MEP list of each MA in each MD. Make sure devices in the same MA maintain the same MEP list.

· At the edges of MD and MA, MEPs must be designed at the device port. MIPs can be designed on devices or ports that are not at the edges of an Ethernet network.

Configuring basic CFD settings

Enabling CFD

1. Enter system view.

system-view

2. Enable CFD.

cfd enable

By default, CFD is disabled.

Configuring service instances

About this task

Before configuring the MEPs and MIPs, you must first configure service instances. A service instance is a set of service access points (SAPs), and belongs to an MA in an MD.

In an Ethernet network, for messages handled by the MPs in a service instance, the MD defines the level attribute, and the MA defines the VLAN attribute. The MPs of the MA that carries no VLAN attribute do not belong to any VLAN.

In an MPLS Layer 2 VPN, for messages handled by the MEPs in a service instance, the MD defines the level attribute, and the MA defines the cross-connect attribute.

Procedure

1. Enter system view.

system-view

2. Create an MD.

cfd md md-name [ index index-value ] level level-value [ md-id { dns dns-name | mac mac-address subnumber | none } ]

3. Create a service instance.

¡ In an Ethernet network:

cfd service-instance instance-id ma-id { icc-based ma-name | integer ma-num | string ma-name | vlan-based [ vlan-id ] } [ ma-index index-value ] md md-name [ vlan vlan-id ]

¡ In an MPLS Layer 2 VPN:

cfd service-instance instance-id ma-id { icc-based ma-name | integer ma-num | string ma-name } [ ma-index index-value ] md md-name xconnect-group group-name connection connection-name

Configuring MEPs

About this task

CFD is implemented through various operations on MEPs. As a MEP is configured on a service instance, the MD level and VLAN attribute or cross-connect attribute of the service instance become the attributes of the MEP.

Restrictions and guidelines

In an Ethernet network:

· You can specify an interface as the MEP for only one of the non-VLAN-specific MAs at the same level. In addition, the MEP must be outward facing.

· To create a MEP for an MA that carries VLAN attribute on a Layer 3 Ethernet interface, make sure the following requirements are met:

¡ The device supports subinterfaces.

¡ The subinterfaces support VLAN termination. For more information about VLAN termination, see Layer 2—LAN Switching Configuration Guide.

In an MPLS Layer 2 VPN:

· You can configure only one inward-facing MEP for a CFD service instance.

· An inward-facing MEP can only be configured on an AC interface to detect PW or AC connectivity.

· To specify the VLAN ID when creating a MEP, you must first configure the vlan-type dot1q vid vlan-id-list command and set the same value for the vlan-id-list and vlan vlan-id parameters. For more information about the vlan-type dot1q vid vlan-id-list command, see VLAN termination commands in Layer 2—LAN Switching Command Reference.

· To specify the outer and inner VLAN IDs when creating a MEP, you must first configure the vlan-type dot1q vid second-dot1q command and set the same outer VLAN ID and the same inner VLAN ID in the two commands. For more information about the vlan-type dot1q vid second-dot1q command, see VLAN termination commands in Layer 2—LAN Switching Command Reference.

Prerequisites

Before you configure MEPs, you must configure service instances.

Configuring MEPs in an Ethernet network

1. Enter system view.

system-view

2. Configure a MEP list.

cfd meplist mep-list service-instance instance-id

All created MEPs must be included in the configured MEP list.

3. Enter interface view.

interface interface-type interface-number

4. Create a MEP.

¡ Create a MEP in Layer 2 Ethernet interface view or Layer 2 aggregate interface view.

cfd mep mep-id service-instance instance-id { inbound | outbound }

¡ Create a MEP in Layer 3 Ethernet interface view.

cfd mep mep-id service-instance instance-id outbound

Configuring MEPs in an MPLS Layer 2 VPN

1. Enter system view.

system-view

2. Configure a MEP list.

cfd meplist mep-list service-instance instance-id

The created MEP must be included in the configured MEP list.

3. Enter interface view.

¡ Enter Layer 3 Ethernet interface or Layer 3 aggregate interface view.

interface interface-type interface-number

¡ Enter Layer 3 Ethernet subinterface or Layer 3 aggregate subinterface view.

interface interface-type interface-number.subnumber

4. Create a MEP.

¡ In Layer 3 aggregate interface view or Layer 3 aggregate subinterface view:

cfd mep mep-id service-instance instance-id inbound

¡ In Layer 3 Ethernet interface view:

cfd mep mep-id service-instance instance-id { inbound | outbound }

¡ In Layer 3 Ethernet subinterface view:

cfd mep mep-id service-instance instance-id inbound

cfd mep mep-id service-instance instance-id [ vlan vlan-id | service-vid vlan-id customer-vid vlan-id ] outbound

Configuring MIP auto-generation rules

About this task

As functional entities in a service instance, MIPs respond to various CFD frames, such as LTM and LBM frames. You can configure MIP auto-generation rules for the system to automatically create MIPs.

Any of the following events can cause MIPs to be created or deleted after you have configured the cfd mip-rule command:

· Enabling or disabling CFD.

· Creating or deleting MEPs on a port.

· Changes occur to the VLAN attribute of a port.

· The rule specified in the cfd mip-rule command changes.

Restrictions and guidelines

An MA carrying no VLAN attribute is typically used to detect direct link status. The system cannot generate MIPs for such MAs.

For an MA carrying VLAN attribute, the system does not generate MIPs if the same or a higher level MEP exists on the interface.

Procedure

1. Enter system view.

system-view

2. Configure MIP auto-generation rules.

cfd mip-rule { default | explicit } service-instance instance-id

By default, no rules for generating MIPs are configured, and the system does not automatically create any MIP.

Configuring CFD functions

Configuring CC

About this task

After the CC function is configured, MEPs in an MA can periodically send CCM frames to maintain connectivity.

You must configure CC before you use the MEP ID of the remote MEP to configure other CFD functions. This restriction does not apply when you use the MAC address of the remote MEP to configure other CFD functions.

When the lifetime of a CCM frame expires, the link to the sending MEP is considered disconnected. When setting the CCM interval, use the settings described in Table 1.

Table 1 CCM interval field encoding

CCM interval field	Transmission interval	Maximum CCM lifetime
1	10/3 milliseconds	35/3 milliseconds
2	10 milliseconds	35 milliseconds
3	100 milliseconds	350 milliseconds
4	1 second	3.5 seconds
5	10 seconds	35 seconds
6	60 seconds	210 seconds
7	600 seconds	2100 seconds

NOTE:

· The CCM messages with an interval field value of 1 to 3 are short-interval CCM messages. The CCM messages with an interval field value of 4 to 7 are long-interval CCM messages.

Restrictions and guidelines

When you configure the CCM interval, follow these restrictions and guidelines:

· Configure the same CCM interval field value for all MEPs in the same MA.

· After the CCM interval field is modified, the MEP must wait for another CCM interval before sending CCMs.

Configuring CC in an Ethernet network

1. Enter system view.

system-view

2. (Optional.) Set the CCM interval field.

cfd cc interval interval-value service-instance instance-id

By default, the interval field value is 4.

3. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

4. Enable CCM sending on a MEP.

cfd cc service-instance instance-id mep mep-id enable

By default, CCM sending is disabled on a MEP.

Configuring CC in an MPLS Layer 2 VPN

1. Enter system view.

system-view

2. (Optional.) Set the CCM interval field.

cfd cc interval interval-value service-instance instance-id

By default, the interval field value is 4.

3. Enter interface view.

¡ Enter Layer 3 Ethernet interface or Layer 3 aggregate interface view.

interface interface-type interface-number

¡ Enter Layer 3 Ethernet subinterface or Layer 3 aggregate subinterface view.

interface interface-type interface-number.subnumber

4. Enable CCM sending on a MEP.

cfd cc service-instance instance-id mep mep-id enable

By default, CCM sending is disabled on a MEP.

5. (Optional.) Enable hardware CC for remote MEPs.

cfd hardware-cc service-instance instance-id remote-mep mep-list

By default, hardware CC is disabled for a remote MEP.

Configuring LB

To verify the link state between the local MEP and the remote MEP, execute the following command in any view:

cfd loopback service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ number number ]

Configuring LT

About this task

LT can trace the path between source and target MEPs, and can locate link faults by automatically sending LT messages. The two functions are implemented in the following way:

· Tracing path—The source MEP first sends LTM messages to the target MEP. Based on the LTR messages in response to the LTM messages, the path between the two MEPs is identified.

· LT messages automatic sending—If the source MEP fails to receive CCM frames from the target MEP within 3.5 times the transmission interval, it considers the link faulty. The source MEP then sends LTM frames, with the TTL field set to the maximum value 255, to the target MEP. Based on the returned LTRs, the fault source is located.

Prerequisites

In an Ethernet network, before you configure LT on a MEP in an MA carrying VLAN attribute, create the VLAN to which the MA belongs.

In an MPLS Layer 2 VPN, before you configure LT on a MEP in an MA carrying cross-connect attribute, create the cross-connect to which the MA belongs.

Procedure

1. Identify the path between a source MEP and a target MEP.

cfd linktrace service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ ttl ttl-value ] [ hw-only ]

This command is available in any view.

2. Enter system view.

system-view

3. Enable LT messages automatic sending.

cfd linktrace auto-detection [ size size-value ]

By default, LT messages automatic sending is disabled.

Configuring AIS

About this task

The AIS function suppresses the number of error alarms reported by MEPs.

Restrictions and guidelines

If you enable AIS without configuring a correct AIS frame transmission level, the MEP can suppress error alarms, but cannot send AIS frames to MDs with higher level.

This function can be configured only in Ethernet networks.

Procedure

1. Enter system view.

system-view

2. Enable AIS.

cfd ais enable

By default, AIS is disabled.

3. Configure the AIS frame transmission level.

cfd ais level level-value service-instance instance-id

By default, the AIS frame transmission level is not configured.

The AIS frame transmission level must be higher than the MD level of the service instance.

4. Configure the AIS frame transmission interval.

cfd ais period period-value service-instance instance-id

By default, the AIS frame transmission interval is 1 second.

Configuring one-way LM

About this task

The one-way LM function measures frame loss between MEPs. Frame loss statistics include the number of lost frames, the frame loss ratio, and the average number of lost frames for the source and target MEPs.

Restrictions and guidelines

To configure one-way LM in a Layer 2 VPN, first configure the same frame counting mode on the source MEP and target MEP.

Inward-facing MEPs created in an Ethernet network do not support one-way continual LM.

Configuring the frame counting mode

1. Enter system view.

system-view

2. Enter interface view.

¡ Enter Layer 3 Ethernet interface or Layer 3 aggregate interface view.

interface interface-type interface-number

¡ Enter Layer 3 Ethernet subinterface or Layer 3 aggregate subinterface view.

interface interface-type interface-number.subnumber

3. Configure the frame counting mode.

cfd frame-count mode { dot1p-based | port-based }

By default, no frame counting mode is configured for LM.

This command takes effect only in Layer 2 VPNs.

Configuring short-period LM

To configure short-period LM, execute the following command in any view:

cfd slm service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ dot1p dot1p-value ] [ number number ] [ interval { interval | msec msec-interval } ]

Configuring continual LM

1. Enter system view.

system-view

2. Configure continual LM.

cfd slm continual service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } ] [ dot1p dot1p-value ] [ interval { interval | msec msec-interval }][ period period ]

By default, continual LM is not configured.

Configuring one-way DM

About this task

The one-way DM function measures the one-way frame delay between two MEPs, and monitors and manages the link transmission performance.

Restrictions and guidelines

One-way DM requires that the time settings at the source MEP and the target MEP be the same. For the purpose of frame delay variation measurement, the requirement can be relaxed.

To view the test result, use the display cfd dm one-way history command on the target MEP.

Inward-facing MEPs created in an Ethernet network do not support one-way continual DM.

Configuring short-period DM

To configure one-way DM, execute the following command in any view:

cfd dm one-way service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [dot1p dot1p-value ] [ number number ]

Configuring continual DM

1. Enter system view.

system-view

2. Configure continual DM

cfd dm one-way continual service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ dot1p dot1p-value ][ interval interval ]

By default, continual DM is not configured.

Configuring two-way DM

About this task

The two-way DM function measures the two-way frame delay, average two-way frame delay, and two-way frame delay variation between two MEPs. It also monitors and manages the link transmission performance.

Restrictions and guidelines

Inward-facing MEPs created in an Ethernet network do not support two-way continual DM.

Configuring short-period two-way DM

To configure two-way DM, execute the following command in any view:

cfd dm two-way service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ dot1p dot1p-value ] [ number number ] [ interval interval ]

Configuring continual two-way DM

1. Enter system view.

system-view

2. Configure continual two-way DM.

cfd dm two-way continual service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ dot1p dot1p-value ] [ interval interval ]

By default, continual two-way DM is not configured.

Configuring TST

About this task

The TST function detects bit errors on a link, and monitors and manages the link transmission performance.

Restrictions and guidelines

To view the test result, use the display cfd tst history command on the target MEP.

This function can be configured only in Ethernet networks.

Inward-facing MEPs created in an Ethernet network do not support this function.

Configuring short-period TST

To configure short-period TST, execute the following command in any view:

cfd tst service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ number number ] [ length-of-test length ] [ pattern-of-test { all-zero | prbs } [ with-crc ] ]

Configuring continual TST

1. Enter system view.

system-view

2. Configure continual TST.

cfd tst continual service-instance instance-id mep mep-id { target-mac mac-address | target-mep target-mep-id } [ length-of-test length ] [ pattern-of-test { all-zero | prbs } [ with-crc ] ] [ interval interval ]

By default, continual TST is not configured.

Configuring threshold alarm

About this task

The threshold alarm function allows you to monitor the packet loss ratio, delay, and bit error rate of MEPs and view the monitoring results.

Restrictions and guidelines

The lower limit must be smaller than the upper limit.

Configuring threshold alarm for continual one-way LM

1. Enter system view.

system-view

2. Configure threshold alarm for continual LM.

cfd slm { far-end | near-end } threshold service-instance instance-id mep mep-id { lower-limit lower-limit | upper-limit upper-limit }

This command takes effect only after you configure continual one-way LM.

Configuring threshold alarm for continual two-way DM

1. Enter system view.

system-view

2. Configure threshold alarm for continual two-way DM.

cfd dm two-way threshold service-instance instance-id mep mep-id { lower-limit lower-limit | upper-limit upper-limit }

This command takes effect only after you configure continual two-way DM.

Configuring port collaboration

Restrictions and guidelines

Port collaboration takes effect only on the ports with outward-facing MEPs configured.

Configuring port collaboration for CC

1. Enter system view.

system-view

2. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

3. Specify the port collaboration action for CC.

cfd port-trigger cc-expire action { block | shutdown }

Configuring port collaboration for continual two-way DM

1. Enter system view.

system-view

2. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

3. Specify the port collaboration action for continual two-way DM.

cfd port-trigger dm action { block | shutdown }

4. Return to system view.

quit

5. Configure the lower limit and upper limit for continual two-way DM.

cfd dm two-way threshold service-instance instance-id mep mep-id { lower-limit lower-limit | upper-limit upper-limit } *

By default, the lower limit and upper limit for continual two-way DM are 0 and 4294967295 microseconds, respectively.

Configuring port collaboration for RDI

1. Enter system view.

system-view

2. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

3. Specify the port collaboration action for RDI.

cfd port-trigger rdi action { block | shutdown }

Configuring port collaboration for continual LM

1. Enter system view.

system-view

2. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

3. Specify the port collaboration action for continual LM.

cfd port-trigger slm action { block | shutdown }

4. Return to system view.

quit

5. Configure the lower limit and upper limit for continual LM.

cfd slm { far-end | near-end } threshold service-instance instance-id mep mep-id { lower-limit lower-limit | upper-limit upper-limit } *

By default, the lower limit and upper limit for continual LM are 0 and 100%, respectively.

6. Enable automatic port recovery for continual LM and set the delay time for automatic recovery.

cfd slm port-trigger up-delay delay

By default, the undo cfd port-trigger slm action command is required to bring up a port blocked in continual LM.

Configuring port collaboration for continual TST

1. Enter system view.

system-view

2. Enter Layer 2 or Layer 3 Ethernet interface view or Layer 2 aggregate interface view.

interface interface-type interface-number

3. Specify the port collaboration action for continual TST.

cfd port-trigger tst action { block | shutdown }

4. Return to system view.

quit

5. Configure the lower limit and upper limit for continual TST.

cfd tst threshold service-instance instance-id mep mep-id { lower-limit lower-limit | upper-limit upper-limit } *

By default, the lower limit and upper limit for continual TST are 0 and 100%, respectively.

Verifying and maintaining CFD

Verifying CFD configuration and running status

Verifying basic CFD configuration

Perform display tasks in any view.

· Display CFD status.

display cfd status

· Display MD configuration information.

display cfd md

· Display service instance configuration.

display cfd service-instance [ instance-id ]

Verifying AIS configuration and running status

To verify the AIS configuration and running status on the specified MEP, execute the following command in any view:

display cfd ais [ service-instance instance-id [ mep mep-id ] ]

Verifying MP configuration and running status

Perform display tasks in any view.

· Display MP information.

display cfd mp [ interface interface-type interface-number ]

· Display the attribute and running information of a MEP.

display cfd mep mep-id service-instance instance-id

· Display information about a remote MEP.

display cfd remote-mep service-instance instance-id mep mep-id

· Display the MEP list in a service instance.

display cfd meplist [ service-instance instance-id ]

Displaying CFD packet information

Perform display tasks in any view.

· Display LTR information received by a MEP.

display cfd linktrace-reply [ service-instance instance-id [ mep mep-id ] ]

· Display the content of the LTR messages received as responses to the automatically sent LTMs.

display cfd linktrace-reply auto-detection [ size size-value ]

Displaying and clearing CFD test results

Displaying CFD test results

Perform display tasks in any view.

· Display the one-way DM result on the specified MEP.

display cfd dm one-way history [ service-instance instance-id [ mep mep-id ] ]

· Display the two-way DM result on the specified MEP.

display cfd dm two-way history [ service-instance instance-id [ mep mep-id ] ] [ number number ]

· Display the LM result on the specified MEP.

display cfd slm history [ service-instance instance-id [ mep mep-id ] ] [ number number ]

· Display the TST result on the specified MEP.

display cfd tst history [ service-instance instance-id [ mep mep-id ] ] [ number number ]

Clearing CFD test results

Perform clear tasks in user view.

· Clear the one-way DM result on the specified MEP.

reset cfd dm one-way history [ service-instance instance-id [ mep mep-id ] ]

· Clear the TST result on the specified MEP.

reset cfd tst [ service-instance instance-id [ mep mep-id ] ]

CFD configuration examples

Example: Configuring CFD in an Ethernet network

Network configuration

As shown in Figure 4:

· The network comprises five devices and is divided into two MDs: MD_A (level 5) and MD_B (level 3). All ports belong to VLAN 100, and the MAs in the two MDs all serve VLAN 100. Assume that the MAC addresses of Device A through Device E are 0010-FC01-6511, 0010-FC02-6512, 0010-FC03-6513, 0010-FC04-6514, and 0010-FC05-6515, respectively.

· MD_A has three edge ports: GigabitEthernet 0/0/1 on Device A, GigabitEthernet 0/0/3 on Device D, and GigabitEthernet 0/0/4 on Device E. They are all inward-facing MEPs. MD_B has two edge ports: GigabitEthernet 0/0/3 on Device B and GigabitEthernet 0/0/1 on Device D. They are both outward-facing MEPs.

· In MD_A, Device B is designed to have MIPs when its port is configured with low level MEPs. Port GigabitEthernet 0/0/3 is configured with MEPs of MD_B, and the MIPs of MD_A can be configured on this port. You must configure the MIP generation rule of MD_A as explicit.

· The MIPs of MD_B are designed on Device C, and are configured on all ports. You must configure the MIP generation rule as default.

· Configure CC to monitor the connectivity among all the MEPs in MD_A and MD_B. Configure LB to locate link faults, and use the AIS function to suppress the error alarms that are reported.

· Configure port collaboration on GigabitEthernet 0/0/3 of Device B. After the outward-facing MEP on the interface detects a link fault, the interface is shut down or blocked.

· After the status information of the entire network is obtained, use LT, LM, one-way DM, two-way DM, and TST to detect link faults.

Figure 4 Network diagram

‌

Prerequisites

On each device shown in Figure 4, create VLAN 100 and assign ports GigabitEthernet 0/0/1 through GigabitEthernet 0/0/4 to VLAN 100.

Procedure

1. Enable CFD:

# Enable CFD on Device A.

<DeviceA> system-view

[DeviceA] cfd enable

# Configure Device B through Device E in the same way Device A is configured. (Details not shown.)

2. Configure service instances:

# Create MD_A (level 5) on Device A, and create service instance 1 (in which the MA is identified by a VLAN and serves VLAN 100).

[DeviceA] cfd md MD_A level 5

[DeviceA] cfd service-instance 1 ma-id vlan-based md MD_A vlan 100

# Configure Device E in the same way Device A is configured. (Details not shown.)

# Create MD_A (level 5) on Device B, and create service instance 1 (in which the MA is identified by a VLAN and serves VLAN 100).

[DeviceB] cfd md MD_A level 5

[DeviceB] cfd service-instance 1 ma-id vlan-based md MD_A vlan 100

# Create MD_B (level 3), and create service instance 2 (in which the MA is identified by a VLAN and serves VLAN 100).

[DeviceB] cfd md MD_B level 3

[DeviceB] cfd service-instance 2 ma-id vlan-based md MD_B vlan 100

# Configure Device D in the same way Device B is configured. (Details not shown.)

# Create MD_B (level 3) on Device C, and create service instance 2 (in which the MA is identified by a VLAN and serves VLAN 100).

[DeviceC] cfd md MD_B level 3

[DeviceC] cfd service-instance 2 ma-id vlan-based md MD_B vlan 100

3. Configure MEPs:

# On Device A, configure a MEP list in service instance 1, and create inward-facing MEP 1001 in service instance 1 on GigabitEthernet 0/0/1.

[DeviceA] cfd meplist 1001 4002 5001 service-instance 1

[DeviceA] interface gigabitethernet 0/0/1

[DeviceA-GigabitEthernet0/0/1] cfd mep 1001 service-instance 1 inbound

[DeviceA-GigabitEthernet0/0/1] quit

# On Device B, configure a MEP list in service instances 1 and 2.

[DeviceB] cfd meplist 1001 4002 5001 service-instance 1

[DeviceB] cfd meplist 2001 4001 service-instance 2

# Create outward-facing MEP 2001 in service instance 2 on GigabitEthernet 0/0/3.

[DeviceB] interface gigabitethernet 0/0/3

[DeviceB-GigabitEthernet0/0/3] cfd mep 2001 service-instance 2 outbound

[DeviceB-GigabitEthernet0/0/3] quit

# On Device D, configure a MEP list in service instances 1 and 2.

[DeviceD] cfd meplist 1001 4002 5001 service-instance 1

[DeviceD] cfd meplist 2001 4001 service-instance 2

# Create outward-facing MEP 4001 in service instance 2 on GigabitEthernet 0/0/1.

[DeviceD] interface gigabitethernet 0/0/1

[DeviceD-GigabitEthernet0/0/1] cfd mep 4001 service-instance 2 outbound

[DeviceD-GigabitEthernet0/0/1] quit

# Create inward-facing MEP 4002 in service instance 1 on GigabitEthernet 0/0/3.

[DeviceD] interface gigabitethernet 0/0/3

[DeviceD-GigabitEthernet0/0/3] cfd mep 4002 service-instance 1 inbound

[DeviceD-GigabitEthernet0/0/3] quit

# On Device E, configure a MEP list in service instance 1.

[DeviceE] cfd meplist 1001 4002 5001 service-instance 1

# Create inward-facing MEP 5001 in service instance 1 on GigabitEthernet 0/0/4.

[DeviceE] interface gigabitethernet 0/0/4

[DeviceE-GigabitEthernet0/0/4] cfd mep 5001 service-instance 1 inbound

[DeviceE-GigabitEthernet0/0/4] quit

4. Configure MIPs:

# Configure the MIP generation rule in service instance 1 on Device B as explicit.

[DeviceB] cfd mip-rule explicit service-instance 1

# Configure the MIP generation rule in service instance 2 on Device C as default.

[DeviceC] cfd mip-rule default service-instance 2

5. Configure CC:

# On Device A, enable the sending of CCM frames for MEP 1001 in service instance 1 on GigabitEthernet 0/0/1.

[DeviceA] interface gigabitethernet 0/0/1

[DeviceA-GigabitEthernet0/0/1] cfd cc service-instance 1 mep 1001 enable

[DeviceA-GigabitEthernet0/0/1] quit

# On Device B, enable the sending of CCM frames for MEP 2001 in service instance 2 on GigabitEthernet 0/0/3.

[DeviceB] interface gigabitethernet 0/0/3

[DeviceB-GigabitEthernet0/0/3] cfd cc service-instance 2 mep 2001 enable

[DeviceB-GigabitEthernet0/0/3] quit

# On Device D, enable the sending of CCM frames for MEP 4001 in service instance 2 on GigabitEthernet 0/0/1.

[DeviceD] interface gigabitethernet 0/0/1

[DeviceD-GigabitEthernet0/0/1] cfd cc service-instance 2 mep 4001 enable

[DeviceD-GigabitEthernet0/0/1] quit

# Enable the sending of CCM frames for MEP 4002 in service instance 1 on GigabitEthernet 0/0/3.

[DeviceD] interface gigabitethernet 0/0/3

[DeviceD-GigabitEthernet0/0/3] cfd cc service-instance 1 mep 4002 enable

[DeviceD-GigabitEthernet0/0/3] quit

# On Device E, enable the sending of CCM frames for MEP 5001 in service instance 1 on GigabitEthernet 0/0/4.

[DeviceE] interface gigabitethernet 0/0/4

[DeviceE-GigabitEthernet0/0/4] cfd cc service-instance 1 mep 5001 enable

[DeviceE-GigabitEthernet0/0/4] quit

6. Configure AIS:

# Enable AIS on Device B. Configure the AIS frame transmission level as 5 and AIS frame transmission interval as 1 second in service instance 2.

[DeviceB] cfd ais enable

[DeviceB] cfd ais level 5 service-instance 2

[DeviceB] cfd ais period 1 service-instance 2

7. Configure port collaboration on GigabitEthernet 0/0/3:

# Specify the triggering event as cc-expire and triggered action as shutdown for port collaboration on the interface.

[DeviceB-GigabitEthernet0/0/3] cfd port-trigger cc-expire action shutdown

# Specify the triggering event as rdi and triggered action as block for port collaboration on the interface.

[DeviceB-GigabitEthernet0/0/3] cfd port-trigger rdi action block

[DeviceB-GigabitEthernet0/0/3] quit

Verifying the configuration

1. Verify the LB function when the CC function detects a link fault:

# Enable LB on Device A to check the status of the link between MEP 1001 and MEP 5001 in service instance 1.

[DeviceA] cfd loopback service-instance 1 mep 1001 target-mep 5001

Loopback to MEP 5001 with the sequence number start from 1001-43404:

Reply from 0010-fc05-6515: sequence number=1001-43404 time=5ms

Reply from 0010-fc05-6515: sequence number=1001-43405 time=5ms

Reply from 0010-fc05-6515: sequence number=1001-43406 time=5ms

Reply from 0010-fc05-6515: sequence number=1001-43407 time=5ms

Reply from 0010-fc05-6515: sequence number=1001-43408 time=5ms

Sent: 5 Received: 5 Lost: 0

2. Verify the LT function after the CC function obtains the status information of the entire network:

# Identify the path between MEP 1001 and MEP 5001 in service instance 1 on Device A.

[DeviceA] cfd linktrace service-instance 1 mep 1001 target-mep 5001

Linktrace to MEP 5001 with the sequence number 1001-43462:

MAC address TTL Last MAC Relay action

0010-fc05-6515 63 0010-fc02-6512 Hit

3. Verify the LM function after the CC function obtains the status information of the entire network:

# Use short-period LM to test the frame loss from MEP 1001 to MEP 4002 in service instance 1 on Device A.

[DeviceA] cfd slm service-instance 1 mep 1001 target-mep 4002

Reply from 0010-fc02-6514:

Far-end frame loss : 10 Far-end frame loss rate : 10.00%

Near-end frame loss: 20 Near-end frame loss rate: 20.00%

Reply from 0010-fc02-6514:

Far-end frame loss : 40 Far-end frame loss rate : 40.00%

Near-end frame loss: 40 Near-end frame loss rate: 40.00%

Reply from 0010-fc02-6514:

Far-end frame loss : 0 Far-end frame loss rate : 0.00%

Near-end frame loss: 10 Near-end frame loss rate: 10.00%

Reply from 0010-fc02-6514:

Far-end frame loss : 30 Far-end frame loss rate : 30.00%

Near-end frame loss: 30 Near-end frame loss rate: 30.00%

Average:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

Packet statistics:

Sent LMMs: 5 Received: 5

# Use continual LM to test the frame loss from MEP 1001 to MEP 5001 in service instance 1 on Device A.

[DeviceA] cfd slm continual service-instance 1 mep 1001 target-mep 5001

# Display the LM result on MEP 5001 in service instance 1 on Device A.

[DeviceA] display cfd slm history service-instance 1 mep 1001

Service instance: 1

MEP ID: 1001

Send status: Testing

Test state: Active

Reply from 0010-fc04-6514:

Far-end frame loss : 10 Far-end frame loss rate : 10.00%

Near-end frame loss: 20 Near-end frame loss rate: 20.00%

Reply from 0010-fc04-6514:

Far-end frame loss : 40 Far-end frame loss rate : 40.00%

Near-end frame loss: 40 Near-end frame loss rate: 40.00%

Reply from 0010-fc04-6514:

Far-end frame loss : 0 Far-end frame loss rate : 0.00%

Near-end frame loss: 10 Near-end frame loss rate: 10.00%

Reply from 0010-fc04-6514:

Far-end frame loss : 30 Far-end frame loss rate : 30.00%

Near-end frame loss: 30 Near-end frame loss rate: 30.00%

Reply from 0010-fc04-6514:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

Average:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

4. Verify the one-way DM function after the CC function obtains the status information of the entire network:

# Test the one-way frame delay from MEP 1001 to MEP 4002 in service instance 1 on Device A.

[DeviceA] cfd dm one-way service-instance 1 mep 1001 target-mep 4002

5 1DMs have been sent. Please check the result on the remote device.

# Display the one-way DM result on MEP 4002 in service instance 1 on Device D.

[DeviceD] display cfd dm one-way history service-instance 1 mep 4002

Service instance: 1

MEP ID: 4002

Sent 1DM total number: 0

Received 1DM total number: 5

Frame delay: 10ms 9ms 11ms 5ms 5ms

Delay average: 8ms

Delay variation: 5ms 4ms 6ms 0ms 0ms

Variation average: 3ms

5. Verify the two-way DM function after the CC function obtains the status information of the entire network:

# Use short-period two-way DM to test the two-way frame delay from MEP 1001 to MEP 4002 in service instance 1 on Device A.

[DeviceA] cfd dm two-way service-instance 1 mep 1001 target-mep 4002

Frame delay:

Reply from 0010-fc04-6514: 10us

Reply from 0010-fc04-6514: 9us

Reply from 0010-fc04-6514: 11us

Reply from 0010-fc04-6514: 5us

Average: 8us

Frame delay variation: 1us 2us 6us 0us

Average: 2us

Packet statistics:

Sent DMMs: 5 Received: 5 Lost: 0

# Use continual two-way DM to test the two-way frame delay from MEP 1001 to MEP 4002 in service instance 1 on Device A.

[DeviceA] cfd dm two-way continual service-instance 1 mep 1001 target-mep 4002

# Display the two-way DM result on MEP 1001 in service instance 1 on Device A.

[DeviceA] display cfd dm two-way history service-instance 1 mep 1001

Service instance: 1

MEP ID: 1001

Send status: Testing

Frame delay:

Reply from 0010-fc04-6514: 564us

Reply from 0010-fc04-6514: 606us

Reply from 0010-fc04-6514: 650us

Reply from 0010-fc04-6514: 626us

Reply from 0010-fc04-6514: 660us

Average: 621us

Frame delay variation: 42us 44us 24us 34us

Average: 36us

Packet statistics:

Sent DMMs: 5 Received: 5 Lost: 0

6. Verify the TST function after the CC function obtains the status information of the entire network:

# Use short-period TST to test the bit errors on the link from MEP 1001 to MEP 4002 in service instance 1 on Device A.

[DeviceA] cfd tst service-instance 1 mep 1001 target-mep 4002

5 TSTs have been sent. Please check the result on the remote device.

# Display the TST result on MEP 4002 in service instance 1 on Device D.

[DeviceD] display cfd tst history service-instance 1 mep 4002

Service instance: 1

MEP ID: 4002

Send status: Testing

Received from 0010-fc01-6511, Bit True, sequence number 0

Received from 0010-fc01-6511, Bit True, sequence number 1

Received from 0010-fc01-6511, Bit True, sequence number 2

Received from 0010-fc01-6511, Bit True, sequence number 3

Received from 0010-fc01-6511, Bit True, sequence number 4

Sent TST total number: 7

Received TST total number: 5

Received bit error TST number: 0

Percentage of error messages: 0.00%

Example: Configuring CFD in a Layer 2 VPN (L2VPN networking)

Network configuration

As shown in Figure 5:

· Configure a static PW between PE 1 and PE 2 to enable CE 1 and CE 2 to communicate with each other. Assume that the MAC addresses of Device A through Device D are 0010-FC01-6511, 0010-FC02-6512, 0010-FC03-6513, and 0010-FC04-6514, respectively.

· Configure GigabitEthernet 0/0/1.1 on Device A and Device B as AC interfaces, and associate them with cross-connect svc of cross-connect group vpna.

· Assign the network to MD_A (level 5). MD_A has two edge interfaces: GigabitEthernet 0/0/1.1 on Device A and GigabitEthernet 0/0/1.1 on Device B. They are both inward-facing MEPs.

· Configure CC to monitor the connectivity between the inward-facing MEPs. Configure LB to locate link faults.

· After the status information of the entire network is obtained, use LT, LM, and DM to detect link faults.

Figure 5 Network diagram

‌

Procedure

1. Configure a static PW. (Details not shown.)

For information about configuring a static PW, see MPLS L2VPN in MPLS Configuration Guide.

2. Enable CFD:

# Enable CFD on Device A.

<DeviceA> system-view

[DeviceA] cfd enable

# Configure Device B in the same way Device A is configured. (Details not shown.)

3. Configure service instances:

# Create MD_A (level 5) on Device A, and create service instance 1 (in which the MA is identified by vpnma and serves cross-connect svc of cross-connect group vpna).

[DeviceA] cfd md MD_A level 5

[DeviceA] cfd service-instance 1 ma-id string vpnma md MD_A xconnect-group vpna connection svc

# Configure Device B in the same way Device A is configured. (Details not shown.)

4. Configure MEPs:

# On Device A, configure a MEP list in service instance 1, and create inward-facing MEP 1001 in service instance 1 on GigabitEthernet 0/0/1.1.

[DeviceA] cfd meplist 1001 2001 service-instance 1

[DeviceA] interface gigabitethernet 0/0/1.1

[DeviceA-GigabitEthernet0/0/1.1] cfd mep 1001 service-instance 1 inbound

[DeviceA-GigabitEthernet0/0/1.1] quit

# On Device B, configure a MEP list in service instance 1, and create inward-facing MEP 2001 in service instance 1 on GigabitEthernet 0/0/1.1.

[DeviceB] cfd meplist 1001 2001 service-instance 1

[DeviceB] interface gigabitethernet 0/0/1.1

[DeviceB-GigabitEthernet0/0/1.1] cfd mep 2001 service-instance 1 inbound

[DeviceB-GigabitEthernet0/0/1.1] quit

5. Configure CC:

# On Device A, enable the sending of CCM frames for MEP 1001 in service instance 1 on GigabitEthernet 0/0/1.1.

[DeviceA] interface gigabitethernet 0/0/1.1

[DeviceA-GigabitEthernet0/0/1.1] cfd cc service-instance 1 mep 1001 enable

[DeviceA-GigabitEthernet0/0/1.1] quit

# On Device B, enable the sending of CCM frames for MEP 2001 in service instance 1 on GigabitEthernet 0/0/1.1.

[DeviceB] interface gigabitethernet 0/0/1.1

[DeviceB-GigabitEthernet0/0/1.1] cfd cc service-instance 1 mep 2001 enable

[DeviceB-GigabitEthernet0/0/1.1] quit

6. Configure the frame counting mode:

# Configure the frame counting mode as port-based for GigabitEthernet 0/0/1.1 on Device A.

[DeviceA] interface gigabitethernet 0/0/1.1

[DeviceA-GigabitEthernet0/0/1.1] cfd frame-count mode port-based

[DeviceA-GigabitEthernet0/0/1.1] quit

# Configure the frame counting mode as port-based for GigabitEthernet 0/0/1.1 on Device B.

[DeviceB] interface gigabitethernet 0/0/1.1

[DeviceB-GigabitEthernet0/0/1.1] cfd frame-count mode port-based

[DeviceB-GigabitEthernet0/0/1.1] quit

Verifying the configuration

1. Verify the LB function when the CC function detects a link fault:

# Enable LB on Device A to check the status of the link between MEP 1001 and MEP 2001 in service instance 1.

[DeviceA] cfd loopback service-instance 1 mep 1001 target-mep 2001

Loopback to MEP 2001 with the sequence number start from 1001-43404:

Reply from 0010-fc02-6512: sequence number=1001-43404 time=5ms

Reply from 0010-fc02-6512: sequence number=1001-43405 time=5ms

Reply from 0010-fc02-6512: sequence number=1001-43406 time=5ms

Reply from 0010-fc02-6512: sequence number=1001-43407 time=5ms

Reply from 0010-fc02-6512: sequence number=1001-43408 time=5ms

Sent: 5 Received: 5 Lost: 0

2. Verify the LT function after the CC function obtains the status information of the entire network:

# Identify the path between MEP 1001 and MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd linktrace service-instance 1 mep 1001 target-mep 2001

Linktrace to MEP 2001 with the sequence number 1001-43462:

MAC address TTL Last MAC Relay action

0010-fc02-6512 63 0010-fc02-6512 Hit

3. Verify the one-way LM function after the CC function obtains the status information of the entire network:

# Use short-period LM to test the frame loss from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd slm service-instance 1 mep 1001 target-mep 2001

Reply from 0010-fc02-6512:

Far-end frame loss : 10 Far-end frame loss rate : 10.00%

Near-end frame loss: 20 Near-end frame loss rate: 20.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 40 Far-end frame loss rate : 40.00%

Near-end frame loss: 40 Near-end frame loss rate: 40.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 0 Far-end frame loss rate : 0.00%

Near-end frame loss: 10 Near-end frame loss rate: 10.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 30 Far-end frame loss rate : 30.00%

Near-end frame loss: 30 Near-end frame loss rate: 30.00%

Average:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

Packet statistics:

Sent LMMs: 5 Received: 5

# Use continual LM to test the frame delay from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd slm continual service-instance 1 mep 1001 target-mep 2001

# Display the one-way LM result on MEP 1001 in service instance 1 on Device A.

[DeviceA] display cfd slm history service-instance 1 mep 1001

Service instance: 1

MEP ID: 1001

Send status: Testing

Test state: Active

Reply from 0010-fc02-6512:

Far-end frame loss : 10 Far-end frame loss rate : 10.00%

Near-end frame loss: 20 Near-end frame loss rate: 20.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 40 Far-end frame loss rate : 40.00%

Near-end frame loss: 40 Near-end frame loss rate: 40.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 0 Far-end frame loss rate : 0.00%

Near-end frame loss: 10 Near-end frame loss rate: 10.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 30 Far-end frame loss rate : 30.00%

Near-end frame loss: 30 Near-end frame loss rate: 30.00%

Reply from 0010-fc02-6512:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

Average:

Far-end frame loss : 20 Far-end frame loss rate : 20.00%

Near-end frame loss: 25 Near-end frame loss rate: 25.00%

Packet statistics:

Sent LMMs: 100 Received: 100

4. Verify the one-way DM function after the CC function obtains the status information of the entire network:

# Use short-period DM to test the frame delay from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd dm one-way service-instance 1 mep 1001 target-mep 2001

5 1DMs have been sent. Please check the result on the remote device.

# Display the one-way DM result on MEP 1001 in service instance 1 on Device B.

[DeviceB] display cfd dm one-way history service-instance 1 mep 2001

Service instance: 1

MEP ID: 2001

Sent 1DM total number: 0

Received 1DM total number: 5

Frame delay: 10us 9us 11us 5us 5us

Delay average: 8us

Frame delay variation: 2us 1us 5us 0us

Variation average: 2us

# Use continual DM to test the frame delay from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd dm one-way continual service-instance 1 mep 1001 target-mep 2001

# Display the one-way DM result on MEP 1001 in service instance 1 on Device B.

[DeviceB] display cfd dm one-way history service-instance 1 mep 2001

Service instance: 1

MEP ID: 2001

Sent 1DM total number: 0

Received 1DM total number: 5

Frame delay: 10us 9us 11us 5us 5us

Delay average: 8us

Frame delay variation: 2us 1us 5us 0us

Variation average: 2us

5. Verify the two-way DM function after the CC function obtains the status information of the entire network:

# Use short-period DM to test the two-way frame delay from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd dm two-way service-instance 1 mep 1001 target-mep 2001

Frame delay:

Reply from 0010-fc02-6512: 10us

Reply from 0010-fc02-6512: 9us

Reply from 0010-fc02-6512: 11us

Reply from 0010-fc02-6512: 5us

Average: 8us

Frame delay variation: 1us 2us 6us 0us

Average: 2us

Packet statistics:

Sent DMMs: 5 Received: 5 Lost: 0

# Use continual DM to test the frame delay from MEP 1001 to MEP 2001 in service instance 1 on Device A.

[DeviceA] cfd dm one-way continual service-instance 1 mep 1001 target-mep 2001

# Display the two-way DM result on MEP 1001 in service instance 1 on Device A.

[DeviceA] display cfd dm two-way history service-instance 1 mep 1001

Service instance: 1

MEP ID: 1001

Send status: Testing

Test state: Active

Frame delay:

Reply from 0010-fc02-6512: 10us

Reply from 0010-fc02-6512: 9us

Reply from 0010-fc02-6512: 11us

Reply from 0010-fc02-6512: 5us

Average: 8us

Frame delay variation: 1us 2us 6us 0us

Average: 2us

Packet statistics:

Sent DMMs: 5 Received: 5 Lost: 0

20-High Availability Configuration Guide

Configuring CFD

Maintenance domain

Maintenance association

Maintenance point

MEP list

MD levels

MA and MP levels

CFD grading example

CFD functions

Continuity check

Loopback

Linktrace

LM

DM

TST

Threshold alarm

Triggering events

Triggered actions

Link recovery

CFD tasks at a glance

Configuring basic CFD settings

Enabling CFD

Configuring service instances

About this task

Configuring MEPs

About this task

Restrictions and guidelines

Prerequisites

Configuring MEPs in an Ethernet network

Configuring MEPs in an MPLS Layer 2 VPN

Configuring MIP auto-generation rules

About this task

Restrictions and guidelines

Procedure

Configuring CFD functions

Configuring CC

About this task

Restrictions and guidelines

Configuring CC in an Ethernet network

Configuring CC in an MPLS Layer 2 VPN

Configuring LB

Configuring LT

About this task

Prerequisites

Procedure

Configuring AIS

About this task

Restrictions and guidelines

Procedure

About this task

Restrictions and guidelines

Configuring the frame counting mode

Configuring short-period LM

Configuring continual LM

About this task

Restrictions and guidelines

Configuring short-period DM

Configuring continual DM

About this task

Restrictions and guidelines

Configuring short-period two-way DM

Configuring continual two-way DM

About this task

Restrictions and guidelines

Configuring short-period TST

Configuring continual TST

About this task

Restrictions and guidelines

Configuring threshold alarm for continual one-way LM

Configuring threshold alarm for continual two-way DM

Restrictions and guidelines

Configuring port collaboration for CC

Configuring port collaboration for continual two-way DM

Configuring port collaboration for RDI

Configuring port collaboration for continual LM

Configuring port collaboration for continual TST

Verifying and maintaining CFD

Verifying basic CFD configuration

Verifying AIS configuration and running status