03-Interface Configuration Guide

02-Ethernet interface configuration

Chapters Download  (190.3 KB)

02-Ethernet interface configuration


Configuring Ethernet interfaces

Your device supports the following types of Ethernet interfaces:

·     Layer 2 Ethernet interfacesPhysical Ethernet interfaces operating at the data link layer (Layer 2) to switch packets.

·     Layer 3 Ethernet interfacesPhysical Ethernet interfaces operating at the network layer (Layer 3) to route packets. You can assign an IP address to a Layer 3 Ethernet interface.

·     Layer-configurable Ethernet interfacesPhysical Ethernet interfaces that can be configured to operate in bridge mode as Layer 2 Ethernet interfaces or in route mode as Layer 3 Ethernet interfaces.

Configuring common Ethernet interface settings

This section describes the settings common to Layer 2 Ethernet interfaces and Layer 3 Ethernet interfaces. For more information about the settings specific to Layer 2 Ethernet interfaces, see "Configuring a Layer 2 Ethernet interface." For more information about the settings specific to Layer 3 Ethernet interfaces, see "Configuring a Layer 3 Ethernet interface."

Ethernet interface naming conventions

When the switches operate in standalone mode, the Ethernet interfaces are named in the format of interface-type A/B/C, where the following definitions apply:

·     A—Represents the slot number of the card.

·     B—Represents the number of a subcard on a card. If the card has no subcards, this value is 0.

·     C—Represents the number of an interface.

When the switches operate in IRF mode, the Ethernet interfaces are named in the format of interface-type A/B/C/D, where the following definitions apply:

·     A—Represents the member ID of an IRF member switch. This value is 1 or 2.

·     B—Represents the slot number of the card.

·     C—Represents the number of a subcard on a card. If the card has no subcards, this value is 0.

·     D—Represents the number of an interface.

Configuring a combo interface

A combo interface is a logical interface that physically comprises 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.

Configuration prerequisites

Before you configure combo interfaces, complete the following tasks:

·     Determine the combo interfaces on your device. Identify the two physical interfaces that belong to each combo interface according to the marks on the device panel.

·     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, Port hardware type is 1000_BASE_T."

¡     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 fiber combo port is active.

 

Splitting a 40-GE interface and combining 10-GE breakout interfaces

IMPORTANT

IMPORTANT:

This feature is not supported on non-default MDCs.

 

Splitting a 40-GE interface into four 10-GE breakout interfaces

IMPORTANT

IMPORTANT:

Before you reboot a switch configured with the using tengige command, save the splitting configuration on the switch even if the switch is an IRF member switch. Otherwise, the splitting configuration cannot take effect.

 

You can use a 40-GE interface as a single interface. To improve port density, reduce costs, and improve network flexibility, you can also split a 40-GE interface into four 10-GE breakout interfaces.

For example, you can split a 40-GE interface FortyGigE 1/1/16 into four 10-GE breakout interfaces Ten-GigabitEthernet 1/1/16:1 through Ten-GigabitEthernet 1/1/16:4.

After you configure this feature on a 40-GE interface, reboot the interface module. The system deletes the 40-GE interface and creates the four 10-GE breakout interfaces.

To split a 40-GE interface into four 10-GE breakout interfaces:

 

Step

Command

Remarks

1.     Enter system view.

system-view

N/A

2.     Enter 40-GE interface view.

interface interface-type interface-number

N/A

3.     Split the 40-GE interface into four 10-GE breakout interfaces.

using tengige

By default, a 40-GE interface is not split and operates as a single interface.

The 10-GE breakout interfaces support the same configuration and attributes as common 10-GE interfaces, except that they are numbered differently.

A 40-GE interface split into four 10-GE breakout interfaces must use a dedicated 1-to-4 cable. For more information about the cables, see H3C S7500E-X Switch Series Installation Guide.

 

Combining four 10-GE breakout interfaces into a 40-GE interface

IMPORTANT

IMPORTANT:

Before you reboot a switch configured with the using fortygige command, save the combining configuration on the switch even if the switch is an IRF member switch. Otherwise, the combining configuration cannot take effect.

 

If you need higher bandwidth on a single interface, you can combine the four 10-GE breakout interfaces into a 40-GE interface.

After you configure this feature on a 10-GE breakout interface, reboot the interface module. The system deletes the four 10-GE breakout interfaces and creates the 40-GE interface.

To combine four 10-GE breakout interfaces into a 40-GE interface:

 

Step

Command

Remarks

1.     Enter system view.

system-view

N/A

2.     Enter the view of any 10-GE breakout interface.

interface interface-type interface-number

N/A

3.     Combine the four 10-GE breakout interfaces into a 40-GE interface.

using fortygige

By default, a 40-GE interface is not split and operates as a single interface.

After you combine the four 10-GE breakout interfaces, replace the dedicated 1-to-4 cable with a dedicated 1-to-1 cable or a 40-GE transceiver module. For more information about the cable or transceiver module, see H3C S7500E-X Switch Series Installation Guide.

 

Configuring basic settings of an Ethernet interface

You can configure an Ethernet interface to operate in one of the following duplex modes:

·     Full-duplex mode—The interface can send and receive packets simultaneously.

·     Half-duplex modeThe interface can only send or receive packets at a given time.

·     Autonegotiation mode—The interface negotiates a duplex mode with its peer.

To configure 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 description for the Ethernet interface.

description text

The default setting is interface-name Interface. For example, GigabitEthernet1/0/1 Interface.

4.     Set the duplex mode for the Ethernet interface.

duplex { auto | full | half }

By default:

·     The duplex mode is full for 10-GE, 40-GE, and 100-GE interfaces.

·     The duplex mode is auto for other Ethernet interfaces.

Copper ports on LSQM2GT24PTSSC0, LSQM2GT24TSSC0, LSQM2GT48SC0, LSQM4GV48SC0, and LSQM2GT48SA0 interface modules and fiber ports do not support the half keyword or autonegotiated half duplex mode.

For Ethernet interfaces connected to the same cable to operate correctly, you must configure the same duplex mode for them.

5.     Set the speed for the Ethernet interface.

speed { 10 | 100 | 1000 | 10000 | 40000 | 100000 | auto }

Support for the keywords of the command depends on the interface type. For more information, see Interface Command Reference.

By default:

·     The speed of a 10-GE XFP fiber port is 10000 Mbps.

·     The speeds of other Ethernet interfaces are autonegotiated.

For Ethernet interfaces connected to the same cable to operate correctly, you must configure the same speed for them.

6.     Set the expected bandwidth for the Ethernet 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, an Ethernet interface is up.

 

Configuring the link mode of an Ethernet interface

WARNING

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.

 

An Ethernet interface can operate in either of the following modes:

·     bridge—The Ethernet interface operates as an Layer 2 interface.

·     route—The Ethernet interface operates as an Layer 3 interface.

This feature is not applicable to IRF ports, internal interfaces on an LSQ OAP module, reflector ports of a remote source group, and EVB-enabled ports. For more information about internal interfaces on an OAP module, see OAA Configuration Guide. For more information about reflector ports, see Network Management and Monitoring Configuration Guide. For more information about EVB, see EVB Configuration Guide.

To configure 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.     Configure the link mode of the Ethernet interface.

port link-mode { bridge | route }

By default, an Ethernet interface operates in bridge mode.

 

Configuring jumbo frame support

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

The Ethernet interface processes jumbo frames in the following ways:

·     When the Ethernet interface is configured to deny jumbo frames, the Ethernet interface discards jumbo frames.

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

¡     Processes jumbo frames within the specified length.

¡     Discards jumbo frames that exceed the specified length.

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 ]

By default, the device allows jumbo frames within 9216 bytes to pass through all Layer 2 Ethernet interfaces.

If you set the value argument multiple times, the most recent configuration takes effect.

 

Configuring physical state change suppression on an Ethernet interface

IMPORTANT

IMPORTANT:

Do not enable this feature on an interface with 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 an interface comes up or goes down, the interface immediately reports the change to the CPU. The CPU then performs the following tasks:

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

·     Automatically generates traps and logs to inform users to take the correct actions.

To prevent frequent physical link flapping from affecting system performance, configure physical state change suppression. You can configure this feature to suppress only link-down events, only link-up events, or both. If an event of the specified type still exists when the suppression interval expires, the system reports the event.

When you configure this feature, follow these guidelines:

·     To suppress only link-down events, configure the link-delay [ msec ] delay-time command.

·     To suppress only link-up events, configure the link-delay [ msec ] delay-time mode up command.

·     To suppress both link-down and link-up events, configure the link-delay [ msec ] delay-time mode updown command.

·     The link-delay command and the link-delay mode command overwrite each other, and whichever is configured last takes effect.

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.     Set the suppression interval for link-down events.

link-delay [ msec ] delay-time

By default, link-down events are not suppressed.

4.     Set the suppression interval for link-up events.

link-delay [ msec ] delay-time mode up

By default, link-up events are not suppressed.

5.     Set the suppression interval for both link-up and link-down events.

link-delay [ msec ] delay-time mode updown

By default, neither link-up nor link-down events are suppressed.

 

Enabling loopback testing on an Ethernet interface

CAUTION

CAUTION:

After you enable this feature on an Ethernet interface, the interface does not forward data traffic.

 

IMPORTANT

IMPORTANT:

This feature is used only for debugging and troubleshooting.

 

Perform this task to determine whether an Ethernet link operates correctly.

Loopback testing includes the following types:

·     Internal loopback testing—Tests the device where the Ethernet interface resides. The Ethernet interface sends outgoing packets back to the local device. If the device fails to receive the packets, the device fails.

·     External loopback testing—Tests the inter-device link. The Ethernet interface sends incoming packets back to the remote device. If the remote device fails to receive the packets, the inter-device link fails

After you enable this feature on an Ethernet interface, the Ethernet interface switches to full duplex mode. After you disable this feature, the Ethernet interface restores to its duplex setting.

Configuration restrictions and guidelines

When you perform loopback tests, follow these restrictions and guidelines:

·     You cannot enable loopback testing on an administratively shut down Ethernet interface (displayed as in ADM or Administratively DOWN state).

·     After you enable loopback testing on an Ethernet interface, the speed, duplex, mdix-mode, port up-mode, and shutdown commands are not available on the Ethernet interface.

·     Do not enable loopback testing on an interface enabled with voice VLAN, MAC learning limit, MAC address learning, 802.1X, or MAC authentication. Otherwise, these features cannot take effect. To enable these features to take effect on the interface, cancel the loopback test and configure the features again.

Configuration procedure

To enable loopback testing 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 loopback testing.

loopback { external | internal }

By default, loopback testing is disabled on an Ethernet interface.

 

Configuring generic flow control on an Ethernet interface

IMPORTANT

IMPORTANT:

·     This feature is not applicable to interfaces that operate in the half duplex mode.

·     Enabling or disabling this feature on an interface will cause the interface to go down and then come up.

 

To avoid dropping packets 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. Generic flow control includes the following types:

·     TxRx-mode generic flow control—Enabled by using the flow-control command. 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 its peer, it suspends sending packets to its peer.

·     Rx-mode generic flow control—Enabled by using the flow-control receive enable command. With Rx-mode generic flow control enabled, an interface can receive flow control frames, but it cannot send flow control frames:

¡     When congestion occurs, the interface cannot send flow control frames to its peer.

¡     When the interface receives a flow control frame from its peer, it suspends sending packets to its 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

When congestion occurs in the network, the local device notifies the peer to stop sending packets carrying the specified 802.1p priority if all of the following conditions exist:

·     Both the local end and the remote end have PFC enabled.

·     Both the local end and the remote end have the priority-flow-control no-drop dot1p command configured.

·     The specified 802.1p priority is in the 802.1p priority list specified by the dot1p-list argument.

·     The local end receives a packet carrying the specified 802.1p priority.

The state of the PFC feature is determined by the PFC configuration on the local end and on the peer end. In Table 1:

·     The first row lists the PFC configuration on the local interface.

·     The first column lists the PFC configuration on the peer.

·     The Enabled and Disabled fields in other cells are possible negotiation results.

Make sure all interfaces that a data flow passes through have the same PFC configuration.

Table 1 PFC configurations and negotiation results

Local (right)

Peer (below)

enable

auto

Default

enable

Enabled

Enabled.

Disabled

auto

Enabled

·     Enabled if negotiation succeeds.

·     Disabled if negotiation fails.

Disabled

Default

Disabled

Disabled.

Disabled

 

Configuration restrictions and guidelines

When you configure PFC, follow these restrictions and guidelines:

·     To perform PFC on an Ethernet interface for packets with an 802.1p priority, make sure the following conditions are met:

¡     PFC is configured in both system view and Ethernet interface view.

¡     The 802.1p priority is in the 802.1p priority list specified by the dot1p-list argument in system view.

¡     The 802.1p priority is in the 802.1p priority list specified by the dot1p-list argument in Ethernet interface view.

·     PFC is applicable only to interfaces on the following interface modules:

¡     EC interface modules.

¡     SF interface modules.

¡     SG interface modules.

·     As for IRF physical interfaces, only interfaces on the following interface modules support PFC:

¡     LSUM1QGS6EC0.

¡     LSUM1TGS24EC0.

·     100-GE interfaces do not support PFC.

·     To ensure the correct operation of IRF and other protocols, do not enable PFC for 802.1p priorities 0, 6, or 7.

·     To avoid packet dropping, apply the same PFC configuration to all interfaces that the packets pass through.

·     If you do not enable PFC on an interface, the interface can receive but cannot process PFC pause frames. To make PFC take effect, you must enable PFC on both ends.

·     The relationship between PFC and generic flow control is shown in Table 2.

Table 2 The relationship between PFC and generic flow control

flow-control

priority-flow-control enable

priority-flow-control no-drop dot1p

Remarks

Unconfigurable

Configured

Configured

After you enable PFC on an interface and for the specified 802.1p priorities, you cannot enable generic flow control on the interface.

Configured

Configurable

Unconfigurable

After you enable generic flow control on an interface, you can enable PFC on the interface but not for the specified 802.1p priorities.

 

Configuration procedure

To configure PFC on an Ethernet interface:

 

Step

Command

Remarks

1.     Enter system view.

system-view

N/A

2.     Enable PFC in auto mode or forcibly.

priority-flow-control { auto | enable }

By default, PFC is disabled.

3.     Enable PFC for 802.1p priorities.

priority-flow-control no-drop dot1p dot1p-list

By default, PFC is disabled for all 802.1p priorities.

4.     Enter Ethernet interface view.

interface interface-type interface-number

N/A

5.     Enable PFC in auto mode or forcibly on the Ethernet interface.

priority-flow-control { auto | enable }

By default, PFC is disabled.

6.     Enable PFC for 802.1p priorities.

priority-flow-control no-drop dot1p dot1p-list

By default, PFC is disabled for all 802.1p priorities.

 

 

NOTE:

·     Use the qos map-table command to map an 802.1p priority to a local priority. For more information about the qos map-table command, see ACL and QoS Command Reference.

·     After you enable PFC for an 802.1p priority, make sure the 802.1p priority uses the default 802.1p-local priority map. For more information about the default 802.1p-local priority map, see ACL and QoS Configuration Guide.

 

Enabling EEE on an Ethernet interface

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

This feature is applicable only to copper ports on the following interface modules:

·     SA interface module: LSQM2GT48SA0.

·     SC interface modules:

¡     LSQM2GT24PTSSC0.

¡     LSQM2GT24TSSC0.

¡     LSQM4GV48SC0.

¡     LSQM2GT48SC0.

·     SF interface module: LSQM1TGT24SF0.

·     For this feature to take effect on an interface on an LSQM1TGT24SF0 interface module, configure the interface and its remote interface to operate at a speed higher than 1000 Mbps.

·     For this feature to take effect on an interface on any other modules, configure the interface to automatically negotiate a speed or duplex mode with the remote end.

To enable EEE 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 EEE on the Ethernet interface.

eee enable

By default, EEE is disabled on an Ethernet interface.

 

Setting the statistics polling interval

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 for the Ethernet interface.

flow-interval interval

By default, the statistics polling interval  is 300 seconds.

 

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

Forcibly bringing up a fiber port

CAUTION

CAUTION:

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

·     Configure both the port up-mode command and the speed or duplex command.

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

 

As shown in Figure 1, a fiber port 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 forcibly brings up a fiber port, even when no fiber links or transceiver modules are present for the fiber port. When 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 restrictions and guidelines:

·     This feature is not applicable to interfaces on the following interface modules:

¡     LSUM1CGC2EC0.

¡     10-GE interfaces installed with a GE SFP transceiver module on an LSUM1TGS24EC0 module.

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

·     A GE fiber port forcibly brought up cannot correctly forward traffic if it is installed with a fiber-to-copper converter, 100/1000-Mbps transceiver module, or 100-Mbps transceiver module. 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

Only GE, 10-GE, 40-GE, and 100-GE fiber ports support this feature.

Copper ports and combo ports do not support this feature.

3.     Forcibly bring up the fiber port.

port up-mode

By default, a fiber port is not forcibly brought up, and the physical state of a fiber port depends on the physical state of the fibers.

 

Configuring a Layer 2 Ethernet interface

Configuring storm suppression

IMPORTANT

IMPORTANT:

PEXs do not support unknown unicast suppression. For more information about PEXs, see Virtual Technologies Configuration Guide.

 

The storm suppression feature ensures that the size of a particular type of traffic (broadcast, multicast, or unknown unicast traffic) does not exceed the threshold 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 an interface. The broadcast-suppression, multicast-suppression, and unicast-suppression commands suppress traffic in hardware. They have less impact on the device performance than the storm-constrain command, which suppresses traffic in software.

Configuration restrictions and guidelines

When you configure storm suppression, follow these restrictions and guidelines:

·     For the same type of traffic, do not configure storm control together with storm suppression. Otherwise, the traffic suppression result is not determined. For more information about storm control, 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.

To determine the suppression threshold that takes effect, see the prompts on the switch.

·     To configure the multicast-suppression command together with the broadcast-suppression command on an PEX physical interface in an IRF 3 system, set the same parameter for both commands. For example, if the multicast suppression threshold is configured in kbps, the broadcast suppression threshold must also be configured in kbps.

Configuration procedure

To set storm suppression thresholds 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 broadcast suppression and set the broadcast suppression threshold.

broadcast-suppression { ratio | pps max-pps | kbps max-kbps }

By default, broadcast suppression is disabled.

4.     Enable multicast suppression and set the multicast suppression threshold.

multicast-suppression { ratio | pps max-pps | kbps max-kbps }

By default, multicast suppression is disabled.

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 suppression is disabled.

 

Configuring storm control on an Ethernet interface

About storm control

Storm control compares broadcast, multicast, 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 an upper threshold.

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

·     Blocks this type of traffic and forwards 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 interface begins to forward the traffic.

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

You can configure an Ethernet interface to output threshold event traps and log messages when monitored traffic meets one of the following conditions:

·     Exceeds the upper threshold.

·     Drops below the lower threshold.

Any of the storm-constrain, broadcast-suppression, multicast-suppression, and unicast-suppression commands can suppress storm on an interface. The broadcast-suppression, multicast-suppression, and unicast-suppression commands suppress traffic in hardware. They have less impact on the device performance than the storm-constrain command, which suppressions traffic 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 restrictions and guidelines

For the same type of traffic, do not configure storm control together with storm suppression. Otherwise, the traffic suppression result is not determined. For more information about storm suppression, 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 statistics 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 longer statistics polling interval.

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 | multicast | unicast } { pps | kbps | ratio } max-pps-values min-pps-values

By default, storm control is disabled.

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 Ethernet interface to output log messages when it detects storm control threshold events.

storm-constrain enable log

By default, the Ethernet interface outputs log messages when monitored traffic exceeds the upper threshold or drops below the lower threshold.

7.     (Optional.) Enable the Ethernet interface to send storm control threshold event traps.

storm-constrain enable trap

By default, the Ethernet interface sends traps when monitored traffic exceeds the upper threshold or drops below the lower threshold from the upper threshold.

 

Setting the MDIX mode of an Ethernet interface

IMPORTANT

IMPORTANT:

Fiber ports do not support the MDIX mode setting.

 

A physical Ethernet interface has 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 a copper Ethernet interface to communicate with its peer, set the MDIX mode of the interface by following these 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 device cannot determine the cable type.

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

·     When a crossover cable is used, perform one of the following operations:

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

¡     Configure 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

IMPORTANT:

Fiber ports do not support this feature.

 

This feature tests the cable connection of an Ethernet interface. The test result includes the cable's status and some physical parameters. If any fault is detected, the test result shows the length from the local port to the faulty point.

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.     Perform a test for 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 the outgoing interface of the entry found 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 bridging on the Ethernet interface.

If no entry is found for the destination MAC address, the switch sends an ARP packet out of all interfaces except the incoming interface. To enable the switch to send the ARP packet out of the incoming interface, enable bridging on the Ethernet interface.

To enable bridging 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 bridging on the Ethernet interface.

port bridge enable

By default, bridging is disabled on the Ethernet interface.

 

Configuring a Layer 3 Ethernet interface

Setting the MTU for an Ethernet interface

The maximum transmission unit (MTU) of an Ethernet interface affects the fragmentation and reassembly of IP packets on the interface. 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 of the Ethernet interface.

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 statistics polling interval.

display counters rate { inbound | outbound } interface [ interface-type [ interface-number ] ]

Display the operational and status information of the specified interfaces.

display interface [ interface-type ] [ brief [ down ] ]

display interface [ interface-type [ interface-number ] ] [ brief [ description ] ]

Display information about dropped packets on the specified interfaces.

display packet-drop { interface [ interface-type [ interface-number ] ] | summary }

Display information about storm control on the specified interfaces.

display storm-constrain [ broadcast | multicast | unicast ] [ interface interface-type interface-number ]

Display the Ethernet statistics (in standalone mode).

display ethernet statistics slot slot-number

Display the Ethernet statistics (in IRF mode).

display ethernet statistics chassis chassis-number slot slot-number

Clear 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 (in standalone mode).

reset ethernet statistics slot slot-number

Clear the Ethernet statistics (in IRF mode).

reset ethernet statistics chassis chassis-number slot slot-number

 

H3C reserves the right to modify its collaterals without any prior notice. For the latest information of the collaterals, please consult H3C sales or call 400 hotline.