The switch series supports Ethernet interfaces, management Ethernet interfaces, Console interfaces, and USB interfaces. For the interface types and the number of interfaces supported by a switch model, see the installation guide.

This document describes how to configure management Ethernet interfaces and Ethernet interfaces.

Ethernet interface naming conventions

The Ethernet interfaces are named in the format of interface type A/B/C. The letters that follow the interface type represent the following elements:

· A—IRF member ID. If the switch is not in an IRF fabric, A is 1 by default.

· B—Card slot number. 0 indicates the interface is a fixed interface of the switch. 1 indicates the interface is on expansion interface-card 1. 2 indicates the interface is on expansion interface-card 2.

· C—Port index.

Configuring a management Ethernet interface

A management interface uses an RJ-45 connector. You can connect the interface to a PC for software loading and system debugging, or connect it to a remote NMS for remote system management.

Support for management Ethernet interfaces depends on the device model. For more information, see the installation guide.

To configure a management Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter management Ethernet interface view.	interface M-GigabitEthernet interface-number	N/A
3. (Optional.) Set the interface description.	description text	The default setting is M-GigabitEthernet0/0/0 Interface.
4. (Optional.) Shut down the interface.	shutdown	By default, the management Ethernet interface is up.

Configuring common Ethernet interface settings

This section describes the settings common to Layer 2 and Layer 3 Ethernet interfaces. You can set an Ethernet interface as a Layer 3 interface by using the port link-mode route command. For more information, see "Configuring the link mode of an Ethernet interface." For more information about the settings specific to Layer 2 and Layer 3 Ethernet interfaces, see "Configuring a Layer 2 Ethernet interface" and "Configuring a Layer 3 Ethernet interface."

Configuring a combo interface (only applicable to S5130-30F-HI switches)

A combo interface is a logical interface that physically contains one fiber combo port and one copper combo port. The two ports share one forwarding channel and one interface view. As a result, they cannot work simultaneously. When you activate one port, the other port is automatically disabled. In the interface view, you can activate the fiber or copper combo port, and configure other port attributes such as the interface rate and duplex mode.

For more information about the number of combo interfaces, see the installation guide.

Configuration prerequisites

Use the display interface command to determine which port (fiber or copper) of each combo interface is active:

· If the copper port is active, the output includes "Media type is twisted pair."

· If the fiber port is active, the output does not include this information.

Also, you can use the display this command in the view of each combo interface to display the combo interface configuration:

· If the fiber port is active, the combo enable fiber command exists in the output.

· If the copper port is active, the combo enable fiber command does not exist in the output.

Changing the active port of a combo interface

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Activate the copper combo port or fiber combo port.	combo enable { copper \| fiber }	By default, the copper combo port is active.

Configuring basic settings of an Ethernet interface

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Set the interface description.	description text	The default setting is in the format of interface-name Interface. For example, GigabitEthernet1/0/1 Interface.
4. Set the duplex mode of the Ethernet interface.	duplex { auto \| full \| half }	The default setting is auto for Ethernet interfaces. Copper ports operating at 1000 Mbps or 10 Gbps and fiber ports do not support the half keyword.
5. Set the port speed.	speed { 10 \| 100 \| 1000 \| 10000 \| 20000 \| auto }	The default setting is auto for Ethernet interfaces. Support for the keywords depends on the interface type. For more information, see Layer 2—LAN Switching Command Reference. An interface on an LSWM2SP2PM or LSWM2XGT2PM interface card supports only the 10000 keyword.
6. Configure the expected bandwidth of the interface.	bandwidth bandwidth-value	By default, the expected bandwidth (in kbps) is the interface baud rate divided by 1000.
7. Restore the default settings for the Ethernet interface.	default	N/A
8. Bring up the Ethernet interface.	undo shutdown	By default, Ethernet interfaces are in up state.

Configuring the link mode of an Ethernet interface

CAUTION:

After you change the link mode of an Ethernet interface, all commands (except the shutdown and combo enable commands) on the Ethernet interface are restored to their defaults in the new link mode.

The interfaces on this switch series can operate either as Layer 2 or Layer 3 Ethernet interfaces.

You can set the link mode to bridge or route.

To change the link mode of an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Change the link mode of the Ethernet interface.	port link-mode { bridge \| route }	By default, Ethernet interfaces operate in bridge mode.

Configuring jumbo frame support

An Ethernet interface might receive some frames larger than the standard Ethernet frame size during high-throughput data exchanges, such as file transfers. These frames are called jumbo frames.

The interface processes jumbo frames in the following ways:

· When the Ethernet interface is configured to deny jumbo frames (by using the undo jumboframe enable command), the Ethernet interface discards jumbo frames without further processing.

· When the Ethernet interface is configured with jumbo frame support, the Ethernet interface performs the following operations:

¡ Processes jumbo frames within the specified length.

¡ Discards jumbo frames exceeding the specified length without further processing.

To configure jumbo frame support in interface view:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Configure jumbo frame support.	jumboframe enable [ value ]	In Release 1118P02, the switch allows jumbo frames within 10000 bytes to pass through all Ethernet interfaces by default. In Release 1122 and later, the switch allows jumbo frames within 12288 bytes to pass through all Ethernet interfaces by default.

Configuring physical state change suppression on an Ethernet interface

IMPORTANT:

Do not configure physical state change suppression on an Ethernet interface that has RRPP, MSTP, or Smart Link enabled.

The physical link state of an Ethernet interface is either up or down. Each time the physical link of a port comes up or goes down, the interface immediately reports the change to the CPU. The CPU then performs the following operations:

· Notifies the upper-layer protocol modules (such as routing and forwarding modules) of the change for guiding packet forwarding.

· Automatically generates traps and logs, informing the user to take the correct actions.

To prevent frequent physical link flapping from affecting system performance, configure physical state change suppression to suppress the reporting of physical link state changes. The system reports physical layer changes only when the suppression interval expires.

When the link-delay delay-time command is configured:

· The link-down event is not reported to the CPU unless the interface is still down when the suppression interval (delay-time) expires.

· The link-up event is immediately reported.

When the link-delay delay-time mode up command is configured:

· The link-up event is not reported to the CPU unless the interface is still up when the suppression interval (delay-time) expires.

· The link-down event is immediately reported.

When the link-delay delay-time mode updown command is configured:

· The link-down event is not reported to the CPU unless the interface is still down when the suppression interval (delay-time) expires.

· The link-up event is not reported to the CPU unless the interface is still up when the suppression interval (delay-time) expires.

To configure physical state change suppression on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Configure physical state change suppression on the interface.	link-delay [ msec ] delay-time [ mode { up \| updown }]	By default, the link-down or link-up event is immediately reported to the CPU. If you configure this command multiple times on an Ethernet interface, the most recent configuration takes effect.

Performing a loopback test on an Ethernet interface

If an Ethernet interface does not work correctly, you can perform a loopback test on it to identify the problem. An Ethernet interface in a loopback test does not forward data traffic.

Loopback tests include the following types:

· Internal loopback test—Tests all on-chip functions related to the Ethernet interface.

· External loopback test—Tests the hardware of the Ethernet interface. To perform an external loopback test on the Ethernet interface, connect a loopback plug to the Ethernet interface. The switch sends test packets out of the interface, which are expected to loop over the plug and back to the interface. If the interface fails to receive any test packets, the hardware of the interface is faulty.

Configuration restrictions and guidelines

· On an administratively shut down Ethernet interface (displayed as in ADM or Administratively DOWN state), you cannot perform an internal or external loopback test.

· The speed, duplex, mdix-mode, and shutdown commands are not available during a loopback test.

· During a loopback test, the Ethernet interface operates in full duplex mode. When a loopback test is complete, the port returns to its duplex setting.

Configuration procedure

To perform a loopback test on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Perform a loopback test.	loopback { external \| internal }	By default, no loopback test is performed.

Configuring generic flow control on an Ethernet interface

CAUTION:

Configuring generic flow control on an Ethernet interface will cause link-up and link-down events before the interface finally stays up.

To avoid packet drops on a link, you can enable generic flow control at both ends of the link. When traffic congestion occurs at the receiving end, the receiving end sends a flow control (Pause) frame to ask the sending end to suspend sending packets.

· With TxRx mode generic flow control enabled, an interface can both send and receive flow control frames. When congestion occurs, the interface sends a flow control frame to its peer. When the interface receives a flow control frame from the peer, it suspends sending packets.

· With Rx flow mode generic control enabled, an interface can receive flow control frames, but it cannot send flow control frames. When the interface receives a flow control frame from its peer, it suspends sending packets to the peer. When congestion occurs, the interface cannot send flow control frames to the peer.

To handle unidirectional traffic congestion on a link, configure the flow-control receive enable command at one end and the flow-control command at the other end. To enable both ends of a link to handle traffic congestion, configure the flow-control command at both ends.

To enable generic flow control on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable generic flow control.	· Enable TxRx mode generic flow control: flow-control · Enable Rx mode generic flow control: flow-control receive enable	By default, generic flow control is disabled on an Ethernet interface.

Configuring PFC on an Ethernet interface

PFC performs flow control based on 802.1p priorities. With PFC enabled, an interface requires its peer to suspend sending packets with certain 802.1p priorities when congestion occurs. By decreasing the transmission rate, PFC helps avoid packet loss.

If you enable PFC and configure the priority-flow-control no-drop dot1p dot1p-list command on both ends, the local port processes a received packet as follows when network congestion occurs:

· If PFC is enabled for the 802.1p priority carried in the packet, the local port perform the following tasks:

¡ Accepts the packet.

¡ Notifies the peer to stop sending packets carrying the 802.1p priority until the congestion is removed.

· If PFC is disabled for the 802.1p priority carried in the packet, the local port drops the packet.

To configure PFC on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable PFC on the interface through automatic negotiation or forcibly.	priority-flow-control { auto \| enable }	By default, PFC is disabled.
4. Enable PFC for 802.1p priorities.	priority-flow-control no-drop dot1p dot1p-list	By default, PFC is disabled for all 802.1p priorities.

When you configure PFC, follow these guidelines:

· To perform PFC on a network port of an IRF member device, configure PFC on both the network port and the IRF physical ports. For information about IRF, see IRF configuration Guide.

· To ensure correct operations of IRF and other protocols, H3C recommends not enabling PFC for 802.1p priorities 0, 6, and 7.

· Perform the same PFC configuration on all ports that traffic travels through.

· A port can receive PFC pause frames regardless of whether PFC is enabled on the port. However, only a port with PFC enabled can process PFC pause frames. To make PFC take effect, make sure PFC is enabled on both the local end and the peer end.

The relationship between the PFC feature and the generic flow control feature is shown in Table 1.

Table 1 The relationship between the PFC feature and the generic flow control feature

flow-control	priority-flow-control enable	priority-flow-control no-drop dot1p	Remarks
Unconfigurable	Configured	Configured	You cannot enable flow control by using the flow-control command on a port where PFC is enabled and PFC is enabled for the specified 802.1p priority values.
Configured	Configurable	Unconfigurable	· On a port configured with the flow-control command, you can enable PFC, but you cannot enable PFC for specific 802.1p priorities. · Enabling both generic flow control and PFC on a port disables the port from sending common or PFC pause frames to inform the peer of congestion conditions. However, the port can still handle common and PFC pause frames from the peer.

flow-control

priority-flow-control enable

priority-flow-control no-drop dot1p

Remarks

Unconfigurable

Configured

You cannot enable flow control by using the flow-control command on a port where PFC is enabled and PFC is enabled for the specified 802.1p priority values.

Configured

Configurable

Unconfigurable

· On a port configured with the flow-control command, you can enable PFC, but you cannot enable PFC for specific 802.1p priorities.

· Enabling both generic flow control and PFC on a port disables the port from sending common or PFC pause frames to inform the peer of congestion conditions. However, the port can still handle common and PFC pause frames from the peer.

Enabling energy saving features on an Ethernet interface

Enabling auto power-down on an Ethernet interface

IMPORTANT:

Fiber ports do not support this feature.

When the auto power-down feature is enabled on an interface and the interface has been down for a certain period of time, both of the following events occur:

· The switch automatically stops supplying power to the interface.

· The interface enters the power save mode.

The time period depends on the chip specifications and is not configurable.

When the interface comes up, both of the following events occur:

· The switch automatically restores power supply to the interface.

· The interface enters its normal state.

To enable auto power-down on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable auto power-down.	port auto-power-down	By default, auto power-down is disabled.

Enabling EEE energy saving for Ethernet interfaces in up state

IMPORTANT:

Fiber ports do not support this feature.

With the Energy Efficient Ethernet (EEE) energy saving feature, a link-up port enters the low power state if it has not received any packet for a certain period of time. The time period depends on the chip specifications and is not configurable. When a packet arrives later, the switch automatically restores power supply to the interface and the port enters the normal state.

To enable EEE energy saving:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable EEE energy saving.	eee enable	By default, EEE energy saving is disabled.

Setting the statistics polling interval

To set the statistics polling interval in Ethernet interface view:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Set the statistics polling interval.	flow-interval interval	By default, the statistics polling interval is 300 seconds.

To display the interface statistics collected in the last polling interval, use the display interface command.

To clear interface statistics, use the reset counters interface command.

Enabling automatic negotiation for speed downgrading

Perform this task to enable interfaces at two ends of a link to automatically negotiate about downgrading their speed to 100 Mbps when the following conditions exist:

· The interfaces automatically negotiate a speed of 1000 Mbps.

· The interfaces can only operate at 100 Mbps because of link restrictions.

This feature is available only on 1000-Mbps Ethernet interfaces.

To enable automatic negotiation for speed downgrading:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable automatic negotiation for speed downgrading.	speed auto downgrade	By default, automatic negotiation for speed downgrading is enabled.

Configuring a Layer 2 Ethernet interface

Configuring storm suppression

You can use the storm suppression feature to limit the size of a particular type of traffic (broadcast, multicast, or unknown unicast traffic) on an interface. When the broadcast, multicast, or unknown unicast traffic on the interface exceeds this threshold, the system discards packets until the traffic drops below this threshold.

Any of the storm-constrain, broadcast-suppression, multicast-suppression, and unicast-suppression commands can suppress storm on a port. The broadcast-suppression, multicast-suppression, and unicast-suppression commands suppress traffic in hardware. They have less impact on device performance than the storm-constrain command, which performs suppression in software.

Configuration guidelines

For the same type of traffic, do not configure the storm constrain command together with any of the broadcast-suppression, multicast-suppression, and unicast-suppression commands. Otherwise, the traffic suppression result is not determined. For more information about the storm-constrain command, see "Configuring storm control on an Ethernet interface."

When you configure the suppression threshold in kbps, the actual suppression threshold might be different from the configured one as follows:

· If the configured value is smaller than 64, the value of 64 takes effect.

· If the configured value is greater than 64 but not an integer multiple of 64, the integer multiple of 64 that is greater than and closest to the configured value takes effect.

For the suppression threshold that takes effect, see the prompt on the switch.

Configuration procedure

To set storm suppression thresholds on one or multiple Ethernet interfaces:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Enable broadcast suppression and set the broadcast suppression threshold.	broadcast-suppression { ratio \| pps max-pps \| kbps max-kbps }	By default, broadcast traffic is allowed to pass through an interface.
4. Enable multicast suppression and set the multicast suppression threshold.	multicast-suppression { ratio \| pps max-pps \| kbps max-kbps }	By default, multicast traffic is allowed to pass through an interface.
5. Enable unknown unicast suppression and set the unknown unicast suppression threshold.	unicast-suppression { ratio \| pps max-pps \| kbps max-kbps }	By default, unknown unicast traffic is allowed to pass through an interface.

Configuring storm control on an Ethernet interface

Storm control compares broadcast, multicast, known unicast, and unknown unicast traffic regularly with their respective traffic thresholds on an Ethernet interface. For each type of traffic, storm control provides a lower threshold and a higher threshold.

For management purposes, you can configure the interface to output threshold event traps and log messages when monitored traffic meets one of the following conditions:

· Exceeds the upper threshold.

· Falls below the lower threshold from the upper threshold.

Depending on your configuration, when a particular type of traffic exceeds its upper threshold, the interface does either of the following:

· Blocks this type of traffic, while forwarding other types of traffic—Even though the interface does not forward the blocked traffic, it still counts the traffic. When the blocked traffic drops below the lower threshold, the port begins to forward the traffic.

· Goes down automatically—The interface goes down automatically and stops forwarding any traffic. When the blocked traffic is detected dropping below the lower threshold, the port does not forward the traffic. To bring up the interface, use the undo shutdown command or disable the storm control feature.

Any of the storm-constrain, broadcast-suppression, multicast-suppression, and unicast-suppression commands can suppress storm on a port. The broadcast-suppression, multicast-suppression, and unicast-suppression commands suppress traffic in hardware, and have less impact on device performance than the storm-constrain command, which performs suppression in software.

Storm control uses a complete polling cycle to collect traffic data, and analyzes the data in the next cycle. An interface takes one to two polling intervals to take a storm control action.

Configuration guidelines

For the same type of traffic, do not configure the storm constrain command together with any of the broadcast-suppression, multicast-suppression, and unicast-suppression commands. Otherwise, the traffic suppression result is not determined. For more information about the broadcast-suppression, multicast-suppression, and unicast-suppression commands, see "Configuring storm suppression."

Configuration procedure

To configure storm control on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. (Optional.) Set the traffic polling interval of the storm control module.	storm-constrain interval seconds	The default setting is 10 seconds. For network stability, use the default or set a higher traffic polling interval (10 seconds).
3. Enter Ethernet interface view.	interface interface-type interface-number	N/A
4. (Optional.) Enable storm control, and set the lower and upper thresholds for broadcast, multicast, or unknown unicast traffic.	storm-constrain { broadcast \| known-unicast \| multicast \| unicast } { pps \| kbps \| ratio } max-pps-values min-pps-values	By default, storm control is disabled. The known-unicast keyword is available in Release 1122 and later.
5. Set the control action to take when monitored traffic exceeds the upper threshold.	storm-constrain control { block \| shutdown }	By default, storm control is disabled.
6. (Optional.) Enable the interface to log storm control threshold events.	storm-constrain enable log	By default, the interface outputs log messages when monitored traffic exceeds the upper threshold or falls below the lower threshold from the upper threshold.
7. (Optional.) Enable the interface to send storm control threshold event traps.	storm-constrain enable trap	By default, the interface sends traps when monitored traffic exceeds the upper threshold or drops below the lower threshold from the upper threshold.

Forcibly bringing up a fiber port

CAUTION:

The following operations on a fiber port will cause link updown events before the port finally stays up:

· Configure the port up-mode command and the speed or duplex command at the same time.

· Install or remove fiber links or transceiver modules after you forcibly bring up the fiber port.

IMPORTANT:

Copper ports do not support this feature.

As shown in Figure 1, a fiber port typically uses separate fibers for transmitting and receiving packets. The physical state of the fiber port is up only when both transmit and receive fibers are physically connected. If one of the fibers is disconnected, the fiber port does not work.

To enable a fiber port to forward traffic over a single link, you can use the port up-mode command. This command brings up a fiber port by force, even when no fiber links or optical modules are present. If one fiber link is present and up, the fiber port can forward packets over the link unidirectionally.

Figure 1 Forcibly bring up a fiber port

Configuration restrictions and guidelines

When you forcibly bring up a fiber port, follow these guidelines:

· The port up-mode command is mutually exclusive with either of the shutdown and commands.

· A GE fiber port cannot correctly forward traffic if you configure the port up-mode command on the port and install an electro-optical module, 100/1000-Mbps transceiver module, or 100-Mbps transceiver module into the port. To solve the problem, use the undo port up-mode command on the fiber port.

Configuration procedure

To forcibly bring up a fiber port:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Forcibly bring up the fiber port.	port up-mode	By default, a fiber Ethernet port is not forcibly brought up, and the physical state of a fiber port depends on the physical state of the fibers.

Setting the MDIX mode of an Ethernet interface

IMPORTANT:

Fiber ports do not support the MDIX mode setting.

A physical Ethernet interface contains eight pins, each of which plays a dedicated role. For example, pins 1 and 2 transmit signals, and pins 3 and 6 receive signals. You can use both crossover and straight-through Ethernet cables to connect copper Ethernet interfaces. To accommodate these types of cables, a copper Ethernet interface can operate in one of the following Medium Dependent Interface-Crossover (MDIX) modes:

· MDIX mode—Pins 1 and 2 are receive pins and pins 3 and 6 are transmit pins.

· MDI mode—Pins 1 and 2 are transmit pins and pins 3 and 6 are receive pins.

· AutoMDIX mode—The interface negotiates pin roles with its peer.

To enable the interface to communicate with its peer, set the MDIX mode of the interface mode by using the following guidelines:

· Typically, set the MDIX mode of the interface to AutoMDIX. Set the MDIX mode of the interface to MDI or MDIX only when the switch cannot determine the cable type.

· When a straight-through cable is used, set the interface to operate in the MDIX mode different than its peer.

· When a crossover cable is used, perform either of the following tasks:

¡ Set the interface to operate in the same MDIX mode as its peer.

¡ Set either end to operate in AutoMDIX mode.

To set the MDIX mode of an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Set the MDIX mode of the Ethernet interface.	mdix-mode { automdix \| mdi \| mdix }	By default, a copper Ethernet interface operates in auto mode to negotiate pin roles with its peer.

Testing the cable connection of an Ethernet interface

IMPORTANT:

· If the link of an Ethernet port is up, testing its cable connection will cause the link to go down and then come up.

· Fiber ports do not support this feature.

This feature tests the cable connection of an Ethernet interface and displays cable test results within 5 seconds. The test results include the cable's status and some physical parameters. If any fault is detected, the test results include the length of the faulty cable segment.

To test the cable connection of an Ethernet interface:

Step	Command
1. Enter system view.	system-view
2. Enter Ethernet interface view.	interface interface-type interface-number
3. Test the cable connected to the Ethernet interface.	virtual-cable-test

Enabling bridging on an Ethernet interface

When a packet arrives at an interface, the switch looks up the destination MAC address of the packet in the MAC address table. If an entry is found and the outgoing interface is the same as the incoming interface, the switch drops the packet.

To enable the switch to forward such packets rather than drop them, enable the bridging feature on the Ethernet interface.

To enable bridging on an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
1. Enter Ethernet interface view.	interface interface-type interface-number	N/A
2. Enable bridging on the Ethernet interface.	port bridge enable	By default, bridging is disabled.

Configuring a Layer 3 Ethernet interface

Setting the MTU for an Ethernet interface

The value of maximum transmission unit (MTU) affects the fragmentation and reassembly of IP packets. Typically, you do not need to modify the MTU of an interface.

To set the MTU for an Ethernet interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter Ethernet interface view.	interface interface-type interface-number	N/A
3. Set the MTU.	mtu size	The default setting is 1500 bytes.

Displaying and maintaining an Ethernet interface

Execute display commands in any view and reset commands in user view.

Task	Command
Display interface traffic statistics.	display counters { inbound \| outbound } interface [ interface-type [ interface-number ] ]
Display traffic rate statistics of interfaces in up state over the last sampling interval.	display counters rate { inbound \| outbound } interface [ interface-type [ interface-number ] ]
Display the operational and status information of the specified interface or all interfaces.	display interface [ interface-type [ interface-number ] ]
Display summary information about the specified interface or all interfaces.	display interface [ interface-type [ interface-number ] ] brief [ description ]
Display information about dropped packets on the specified interface or all interfaces.	display packet-drop { interface [ interface-type [ interface-number ] ] \| summary }
Display information about storm control on the specified interface or all interfaces.	display storm-constrain [ broadcast \| known-unicast \| multicast \| unicast ] [ interface interface-type interface-number ]
Display the Ethernet statistics.	display ethernet statistics slot slot-number
Clear the interface statistics.	reset counters interface [ interface-type [ interface-number ] ]
Clear the statistics of dropped packets on the specified interfaces.	reset packet-drop interface [ interface-type [ interface-number ] ]
Clear the Ethernet statistics.	reset ethernet statistics

03-Layer 2-LAN Switching Configuration Guide

Configuring Ethernet interfaces

Configuring common Ethernet interface settings

Configuring a combo interface (only applicable to S5130-30F-HI switches)

Configuration prerequisites

Changing the active port of a combo interface

Configuration restrictions and guidelines

Configuration procedure

Enabling energy saving features on an Ethernet interface

Enabling auto power-down on an Ethernet interface

Enabling EEE energy saving for Ethernet interfaces in up state

Configuring storm suppression

Configuration guidelines

Configuration procedure

Configuring storm control on an Ethernet interface

Configuration guidelines

Configuration procedure

Forcibly bringing up a fiber port

Configuration restrictions and guidelines

Configuration procedure

Configuring a Layer 3 Ethernet interface

Displaying and maintaining an Ethernet interface

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

Service Business

News & Events

Contact Us