03-Layer 2—LAN Switching Command Reference

HomeSupportResource CenterSwitchesH3C S6300 Switch SeriesH3C S6300 Switch SeriesTechnical DocumentsCommandCommand ReferencesH3C S6300 Switch Series Command References-Release 243x-6W10003-Layer 2—LAN Switching Command Reference
01-Ethernet interface commands
Title Size Download
01-Ethernet interface commands 194.08 KB

Ethernet interface commands

Common Ethernet interface commands

bandwidth

Use bandwidth to configure the expected bandwidth of an interface.

Use undo bandwidth to restore the default.

Syntax

bandwidth bandwidth-value

undo bandwidth

Default

The expected bandwidth (in kbps) is the interface baud rate divided by 1000.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

bandwidth-value: Specifies the expected bandwidth in the range of 1 to 400000000 kbps.

Usage guidelines

The expected bandwidth of an interface affects the following items:

·     Bandwidth assignment with CBQ. For more information, see ACL and QoS Configuration Guide.

·     Link costs in OSPF, OSPFv3, and IS-IS. For more information, see Layer 3—IP Routing Configuration Guide.

Examples

# Set the expected bandwidth of Ten-GigabitEthernet 1/0/1 to 1000 kbps.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] bandwidth 1000

Related commands

speed

broadcast-suppression

Use broadcast-suppression to enable broadcast suppression and set the broadcast suppression threshold.

Use undo broadcast-suppression to restore the default.

Syntax

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

undo broadcast-suppression

Default

Ethernet interfaces do not suppress broadcast traffic.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

ratio: Sets the broadcast suppression threshold as a percentage of the interface bandwidth. The value range for this argument is 0 to 100. A smaller value means that less broadcast traffic is allowed to pass through.

pps max-pps: Specifies the maximum number of broadcast packets that the interface can forward per second. The value range for the max-pps argument (in pps) is 0 to 1.4881 × the interface bandwidth. For example, the value range of the max-pps argument for a 40-GE interface is 0 to 59524000.

kbps max-kbps: Specifies the maximum number of kilobits of broadcast traffic that the Ethernet interface can forward per second. The value range for this argument (in kbps) is 0 to the interface bandwidth.

Usage guidelines

The broadcast storm suppression feature limits the size of broadcast traffic to a threshold on an interface. When the broadcast traffic on the interface exceeds this threshold, the system drops packets until the traffic drops below this threshold.

Both storm-constrain and broadcast-suppression can suppress broadcast storm on a port. The broadcast-suppression command uses the chip to physically suppress broadcast traffic. It has less influence on the device performance than the storm-constrain command, which uses software to suppress broadcast traffic.

For the traffic suppression result to be determined, do not configure both the storm constrain broadcast command and the broadcast-suppression command on an 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 device.

Examples

# Set the broadcast suppression threshold to 10000 kbps on Ten-GigabitEthernet1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] broadcast-suppression kbps 10000

The actual value is 10048 on port Ten-GigabitEthernet1/0/1 currently.

Related commands

·     multicast-suppression

·     unicast-suppression

default

Use default to restore the default settings for an Ethernet interface.

Syntax

default

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

CAUTION

CAUTION:

The default command might interrupt ongoing network services. Make sure you are fully aware of the impacts of this command when you use it in a live network.

 

This command might fail to restore the default settings for some commands for reasons such as command dependencies or system restrictions. Use the display this command in interface view to identify these commands, and then use their undo forms or follow the command reference to restore their default settings. If your restoration attempt still fails, follow the error message instructions to resolve the problem.

Examples

# Restore the default settings for Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] default

description

Use description to change the description of an interface.

Use undo description to restore the default.

Syntax

description text

undo description

Default

The description of an interface is the interface name plus Interface (for example, Ten-GigabitEthernet1/0/1 Interface).

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

text: Specifies the interface description, a case-sensitive string of 1 to 255 characters.

Examples

# Change the description of Ten-GigabitEthernet 1/0/1 to lanswitch-interface.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] description lanswitch-interface

display counters

Use display counters to display interface traffic statistics.

Syntax

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

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

inbound: Displays inbound traffic statistics.

outbound: Displays outbound traffic statistics.

interface-type: Specifies an interface type.

interface-number: Specifies an interface number.

Usage guidelines

This command displays traffic statistics within a statistics polling interval specified by the flow-interval command.

To clear the Ethernet interface traffic statistics, use the reset counters interface command. For more information, see "reset counters interface."

If you do not specify an interface type, this command displays traffic statistics for all interfaces that have traffic counters.

If you specify an interface type but do not specify an interface number, this command displays traffic statistics for all interfaces of the specified type.

If you specify an interface type and an interface number, this command displays traffic statistics of the specified interface.

Examples

# Display inbound traffic statistics for all Ten-GigabitEthernet interfaces.

<Sysname> display counters inbound interface ten-gigabitethernet

Interface                Total (pkts)    Broadcast (pkts)    Multicast (pkts)  Err (pkts)

XGE1/0/1                        100                100                  0              0

XGE1/0/2                          0                  0                  0              0

XGE1/0/3                   Overflow           Overflow           Overflow       Overflow

XGE1/0/4                          0                  0                  0              0

 

 Overflow: More than 14 digits (7 digits for column "Err").

       --: Not supported.

Table 1 Command output

Field

Description

Interface

Abbreviated interface name.

Total (pkts)

Total number of packets received or sent through the interface.

Broadcast (pkts)

Total number of broadcast packets received or sent through the interface.

Multicast (pkts)

Total number of multicast packets received or sent through the interface.

Err (pkts)

Total number of error packets received or sent through the interface.

Overflow: More than 14 digits (7 digits for column "Err")

The command displays Overflow if any of the following cases applies:

·     The data length of an Err field value is greater than 7 decimal digits.

·     The data length of a non-Err field value is greater than 14 decimal digits.

--: Not supported

The statistical item is not supported.

 

Related commands

·     flow-interval

·     reset counters interface

display counters rate

Use display counters rate to display traffic rate statistics of interfaces in up state for the most recent statistics polling interval.

Syntax

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

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

inbound: Displays inbound traffic rate statistics.

outbound: Displays outbound traffic rate statistics.

interface-type: Specifies an interface type.

interface-number: Specifies an interface number.

Usage guidelines

The statistics cover only interfaces in up state.

If you specify an interface type, this command displays traffic rate statistics for all up interfaces of the specified type.

If you do not specify an interface type, this command displays traffic rate statistics for all up interfaces that have traffic counters.

If an interface that you specify is always down for the most recent statistics polling interval, the system prompts that the interface does not support the command.

You can use the flow-interval command to set the statistics polling interval.

Examples

# Display the inbound traffic rate statistics for all Ten-GigabitEthernet interfaces.

<Sysname> display counters rate inbound interface ten-gigabitethernet

Interface                   Total (pps)       Broadcast (pps)       Multicast (pps)

XGE1/0/1                           200                   --                    --

XGE1/0/2                           300                   --                    --

XGE1/0/3                           300                   --                    --

 

 Overflow: More than 14 digits.

       --: Not supported.

Table 2 Command output

Field

Description

Interface

Abbreviated interface name.

Total (pkts/sec)

Average rate (in pps) of receiving or sending packets during the statistics polling interval.

Broadcast (pkts/sec)

Average rate (in pps) of receiving or sending broadcast packets during the statistics polling interval.

Multicast (pkts/sec)

Average rate (in pps) of receiving or sending multicast packets during the statistics polling interval.

Overflow: more than 14 decimal digits

The command displays Overflow if the data length of a statistical item is greater than 14 decimal digits.

--: not supported

The statistical item is not supported.

 

Related commands

·     flow-interval

·     reset counters interface

display ethernet statistics

Use display ethernet statistics to display the Ethernet module statistics.

Syntax

display ethernet statistics slot slot-number

Views

User view

Predefined user roles

network-admin

network-operator

Parameters

slot slot-number: Displays the Ethernet module statistics on the specified device. The slot-number argument specifies the IRF member device by its member ID.

Examples

# Display the Ethernet module statistics on IRF member 1.

<Sysname>display ethernet statistics slot 1

ETH receive packet statistics:                                                 

    Totalnum        : 28259          ETHIINum     : 22328                       

    SNAPNum         : 0              RAWNum       : 0                          

    LLCNum          : 5931           UnknownNum   : 0                          

    ForwardNum      : 22922          ARP          : 0                          

    MPLS            : 0              ISIS         : 0                          

    ISIS2           : 0              IP           : 0                          

    IPV6            : 0                                                        

ETH receive error statistics:                                                  

    NullPoint       : 0              ErrIfindex   : 0                          

    ErrIfcb         : 0              IfShut       : 0                          

    ErrAnalyse      : 0              ErrSrcMAC    : 0                          

    ErrHdrLen       : 0                                                        

                                                                               

ETH send packet statistics:                                                     

    L3OutNum        : 412            VLANOutNum   : 0                          

    FastOutNum      : 181            L2OutNum     : 6351                       

ETH send error statistics:                                                      

    MbufRelayNum    : 0              NullMbuf     : 0                          

    ErrAdjFwd       : 0              ErrPrepend   : 0                          

    ErrHdrLen       : 0              ErrPad       : 0                           

    ErrQosTrs       : 0              ErrVLANTrs   : 0                          

    ErrEncap        : 0              ErrTagVLAN   : 0                          

    IfShut          : 0              IfErr        : 0

Table 3 Command output

Field

Description

ETH receive packet statistics

Statistics about the Ethernet packets received on the Ethernet module.

Totalnum

Total number of received packets:

·     ETHIINum—Number of packets encapsulated by using Ethernet-II.

·     SNAPNum—Number of packets encapsulated by using SNAP.

·     RAWNum—Number of packets encapsulated by using RAW.

·     ISIS—Number of packets encapsulated by using IS-IS.

·     LLCNum—Number of packets encapsulated by using LLC.

·     UnknownNum—Number of packets encapsulated by using unknown methods.

·     ForwardNum—Number of packets forwarded at Layer 2 or sent to the CPU.

·     ARP—Number of ARP packets.

·     MPLS—Number of MPLS packets.

·     ISIS—Number of IS-IS packets.

·     ISIS2—Number of large 802.3/802.2 frames encapsulated by using IS-IS.

·     IP—Number of IP packets.

·     IPv6Number of IPv6 packets.

ETH receive error statistics

Statistics about the error Ethernet packets in the outbound direction on the Ethernet module. Errors might be included in packets or occur during the receiving process. The items include:

·     NullPoint—Number of packets that include null pointers.

·     ErrIfindex—Number of packets that include incorrect interface indexes.

·     ErrIfcb—Number of packets that include incorrect interface control blocks.

·     IfShut—Number of packets that are being received when the interface is shut down.

·     ErrAnalyse—Number of packets that include packet parsing errors.

·     ErrSrcMAC—Number of packets that include incorrect source MAC addresses.

·     ErrHdrLen—Number of packets that include header length errors.

ETH send packet statistics

Statistics about the Ethernet packets sent by the Ethernet module:

·     L3OutNum—Number of packets sent out of Layer 3 Ethernet interfaces.

·     VLANOutNum—Number of packets sent out of VLAN interfaces.

·     FastOutNum—Number of packets fast forwarded.

·     L2OutNum—Number of packets sent out of Layer 2 Ethernet interfaces.

·     MbufRelayNum—Number of packets transparently sent.

ETH send error statistics

Statistics about the error Ethernet packets in the outbound direction on the Ethernet module:

·     NullMbuf—Number of packets with null pointers.

·     ErrAdjFwd—Number of packets with adjacency table errors.

·     ErrPrepend—Number of packets with extension errors.

·     ErrHdrLen—Number of packets with header length errors.

·     ErrPad—Number of packets with padding errors.

·     ErrQosTrs—Number of packets that failed to be sent by QoS.

·     ErrVLANTrs—Number of packets that failed to be sent in VLANs.

·     ErrEncap—Number of packets that failed to be sent due to link header encapsulation failures.

·     ErrTagVLAN—Number of packets that failed to be sent due to VLAN tag encapsulation failures.

·     IfShut—Number of packets that are being sent when the interface is shut down.

·     IfErr—Number of packets with incorrect outgoing interfaces.

 

Related commands

reset ethernet statistics

display interface

Use display interface to display Ethernet interface information.

Syntax

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

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

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

interface-type: Specifies an interface type.

interface-number: Specifies an interface number.

brief: Displays brief interface information. If you do not specify this keyword, the command displays detailed interface information.

down: Displays information about interfaces in the down state and the causes. If you do not specify this keyword, the command displays information about interfaces in all states.

description: Displays complete interface descriptions. If you do not specify this keyword, the command displays only the first 27 characters of interface descriptions.

Usage guidelines

If you do not specify an interface type, this command displays information about all interfaces.

If you specify an interface type but do not specify an interface number, this command displays information about all interfaces of that type.

If you specify both the interface type and interface number, this command displays information about the specified interface.

Examples

# Display detailed information about Layer 2 interface Ten-GigabitEthernet 1/0/1.

<Sysname> display interface ten-gigabitethernet 1/0/1

Ten-GigabitEthernet1/0/1

Current state: UP

Line protocol state: UP

IP packet frame type: Ethernet II, hardware address: 00e0-fc00-5932

Description: Ten-GigabitEthernet1/0/1 Interface

Bandwidth: 10000000kbps

Loopback is not set

Media type is stack wire, port hardware type is STACK_SFP_PLUS

10Gbps-speed mode, full-duplex mode

Link speed type is autonegotiation, link duplex type is autonegotiation

Flow-control is not enabled

Maximum frame length: 10000

Allow jumbo frame to pass

Broadcast max-ratio: 100%

Multicast max-ratio: 100%

Unicast max-ratio: 100%

PVID: 1

MDI type: Automdix

Port link-type: Access

 Tagged VLANs:   None

 Untagged VLANs: 1

Port priority: 0

Last link flapping: Never

Last clearing of counters: Never

 Peak input rate: 0 bytes/sec, at 2011-01-01 04:43:29

 Peak output rate: 0 bytes/sec, at 2011-01-01 04:43:29

 Last 300 second input:  0 packets/sec 0 bytes/sec 0%

 Last 300 second output:  0 packets/sec 0 bytes/sec 0%

 Input (total):  1 packets, 336 bytes

          0 unicasts, 0 broadcasts, 1 multicasts, 0 pauses

 Input (normal):  1 packets, - bytes

          0 unicasts, 0 broadcasts, 1 multicasts, 0 pauses

 Input:  0 input errors, 0 runts, 0 giants, 0 throttles

          0 CRC, 0 frame, - overruns, 0 aborts

          - ignored, - parity errors

 Output (total): 2 packets, 664 bytes

          0 unicasts, 0 broadcasts, 2 multicasts, 0 pauses

 Output (normal): 2 packets, - bytes

          0 unicasts, 0 broadcasts, 2 multicasts, 0 pauses

 Output: 0 output errors, - underruns, - buffer failures

          0 aborts, 0 deferred, 0 collisions, 0 late collisions

          0 lost carrier, - no carrier

Table 4 Command output

Field

Description

Current state

Physical link state of the Ethernet interface:

·     Administratively DOWN—The interface has been shut down by using the shutdown command.

·     DOWN—The interface is administratively up, but its physical state is down (possibly because no physical link exists or the link has failed).

·     UP—The Ethernet interface is both administratively and physically up.

Line protocol state

Data link layer state of the interface. The state is determined through parameter negotiation on the link layer.

·     UP—The data link layer protocol is up.

·     UP (spoofing)—The data link layer protocol is up, but the link is an on-demand link or does not exist. This attribute is typical of null interfaces and loopback interfaces.

·     DOWN—The data link layer protocol is down.

·     DOWN (DLDP DOWN)—The data link layer protocol of the interface is down because DLDP detected that the link was unidirectional.

·     DOWN (LAGG DOWN)—The data link layer protocol of the interface is down because the aggregate interface does not have Selected ports.

·     DOWN (OAM DOWN)—The data link layer protocol of the interface is down because OAM detected remote link failures.

·     DOWN (DLDP and LAGG DOWN)—The data link layer protocol of the interface is shut down by DLDP and LAGG.

·     DOWN (DLDP and OAM DOWN)—The data link layer protocol of the interface is shut down by DLDP and OAM.

·     DOWN (OAM and LAGG DOWN)—The data link layer protocol of the interface is shut down by OAM and LAGG.

·     DOWN (DLDP, OAM and LAGG DOWN)—The data link layer protocol of the interface is shut down by DLDP, OAM, and LAGG.

IP packet frame type

Ethernet framing format. PKTFMT_ETHNT_2 indicates that the frames are encapsulated in Ethernet II framing format.

hardware address

MAC address of the interface.

Bandwidth

Expected bandwidth of the interface.

Loopback is set internal

An internal loopback test is running on the Ethernet interface.

Loopback is set external

An external loopback test is running on the Ethernet interface.

Loopback is not set

No loopback test is running on the Ethernet interface.

10Mbps-speed mode

The interface is operating at 10 Mbps.

100Mbps-speed mode

The interface is operating at 100 Mbps.

1000Mbps-speed mode

The interface is operating at 1000 Mbps.

10Gbps-speed mode

The interface is operating at 10 Gbps.

40Gbps-speed mode

The interface is operating at 40 Gbps.

Unknown-speed mode

The speed of the interface is unknown because the speed negotiation fails or the interface is physically disconnected.

half-duplex mode

The interface is operating in half duplex mode.

full-duplex mode

The interface is operating in full duplex mode.

unknown-duplex mode

The duplex mode of the interface is unknown because the duplex mode negotiation fails or the interface is physically disconnected.

Link speed type is autonegotiation

The interface is configured with the speed auto command.

Link speed type is force link

The interface is configured with a speed by using the speed command.

link duplex type is autonegotiation

The interface is configured with the duplex auto command.

link duplex type is force link

The interface is configured with a duplex mode by using the duplex command.

Maximum frame length

Maximum Ethernet frame length allowed on the interface.

Allow jumbo frame to pass

The interface allows jumbo frames to pass through.

Broadcast max-

Broadcast storm suppression threshold in ratio, pps, or kbps. The unit of the threshold depends on your configuration.

Multicast max-

Multicast storm suppression threshold in ratio, pps, or kbps. The unit of the threshold depends on your configuration.

Unicast max-

Unicast storm suppression threshold in ratio, pps, or kbps. The unit of the threshold depends on your configuration.

PVID

Port VLAN ID (PVID) of the Ethernet interface.

MDI type

Cable type (depending on your configuration):

·     automdix.

·     mdi.

·     mdix.

Port link-type

Link type of the interface (depending on your configuration):

·     access.

·     trunk.

·     hybrid.

Tagged VLANs

VLANs for which the interface sends packets without removing VLAN tags.

Untagged VLANs

VLANs for which the interface sends packets after removing VLAN tags.

Port priority

Priority of the interface.

Last link flapping

The amount of time that has elapsed since the most recent physical state change of the interface. This field displays Never if the interface has been physically down since device startup.

Last clearing of counters:  Never

Time when the reset counters interface command was last used to clear statistics on the interface. Never indicates that the reset counters interface command was never used since the device was started.

Peak input rate

Peak rate of inbound traffic in Bps, and the time when the peak inbound traffic rate occurred.

Peak output rate

Peak rate of outbound traffic in Bps, and the time when the peak outbound traffic rate occurred.

Last 300 second input

Average rate of inbound traffic in the last 300 seconds, in pps and Bps, and the ratio of the actual rate to the maximum interface rate.

A hyphen (-) indicates that the statistical item is not supported.

Last 300 second output

Average rate of outbound traffic in the last 300 seconds, in pps and Bps, and the ratio of the actual rate to the maximum interface rate.

A hyphen (-) indicates that the statistical item is not supported.

Input(total)

Inbound traffic statistics (in packets and bytes) for the interface. All inbound normal and abnormal packets and normal pause frames were counted.

Number of inbound unicast packets, number of inbound broadcasts, number of inbound multicasts, and number of inbound pause frames.

A hyphen (-) indicates that the statistical item is not supported.

Input(normal)

Inbound normal traffic and pause frame statistics (in packets and bytes) for the interface.

Number of inbound normal unicast packets, number of inbound normal broadcasts, number of inbound normal multicasts, and number of inbound normal pause frames.

A hyphen (-) indicates that the statistical item is not supported.

input errors

Statistics of incoming error packets.

runts

Number of inbound frames shorter than 64 bytes, in correct format, and containing valid CRCs.

giants

Number of inbound frames larger than the maximum frame length supported on the interface.

·     For an Ethernet interface that does not permit jumbo frames, giants refer to frames larger than 1536 bytes (without VLAN tags) or 1540 bytes (with VLAN tags).

·     For an Ethernet interface that permits jumbo frames, giants refer to frames larger than the maximum length of Ethernet frames that are allowed to pass through, which is configured when you configure jumbo frame support on the interface.

throttles

Number of inbound frames that had a non-integer number of bytes.

CRC

Total number of inbound frames that had a normal length, but contained CRC errors.

frame

Total number of inbound frames that contained CRC errors and a non-integer number of bytes.

overruns

Number of packets dropped because the input rate of the port exceeded the queuing capability.

aborts

Total number of illegal inbound packets:

·     Fragment frames—CRC error frames shorter than 64 bytes. The length can be an integral or non-integral value.

·     Jabber frames—CRC error frames greater than the maximum frame length supported on the Ethernet interface (with an integral or non-integral length).

¡     For an Ethernet interface that does not permit jumbo frames, jabber frames refer to CRC error frames greater than 1536 bytes (without VLAN tags) or 1540 bytes (with VLAN tags).

¡     For an Ethernet interface that permits jumbo frames, jabber frames refer to CRC error frames greater than the maximum length of Ethernet frames that are allowed to pass through the interface.

·     Symbol error frames—Frames that contained at least one undefined symbol.

·     Unknown operation code frames—Non-pause MAC control frames.

·     Length error frames—Frames whose 802.3 length fields did not match the actual frame length (46 to 1500 bytes).

ignored

Number of inbound frames dropped because the receive buffer of the port ran low.

parity errors

Total number of frames with parity errors.

Output(total)

Outbound traffic statistics (in packets and bytes) for the interface. All outbound normal and abnormal packets and normal pause frames were counted.

Number of outbound unicast packets, number of outbound broadcasts, number of outbound multicasts, and number of outbound pause frames.

A hyphen (-) indicates that the statistical item is not supported.

Output(normal)

Outbound normal traffic and pause frame statistics (in packets and bytes) for the interface.

Number of outbound normal unicast packets, number of outbound normal broadcasts, number of outbound normal multicasts, and number of outbound normal pause frames.

A hyphen (-) indicates that the statistical item is not supported.

output errors

Number of outbound packets with errors.

underruns

Number of packets dropped because the output rate of the interface exceeded the output queuing capability. This is a low-probability hardware anomaly.

buffer failures

Number of packets dropped because the transmit buffer of the interface ran low.

aborts

Number of packets that failed to be transmitted, for example, because of Ethernet collisions.

deferred

Number of frames that the interface deferred to transmit because of detected collisions.

collisions

Number of frames that the interface stopped transmitting because Ethernet collisions were detected during transmission.

late collisions

Number of frames that the interface deferred to transmit after transmitting their first 512 bits because of detected collisions.

lost carrier

Number of carrier losses during transmission. This counter increases by one when a carrier is lost, and applies to serial WAN interfaces.

no carrier

Number of times that the port failed to detect the carrier when attempting to send frames. This counter increases by one when a port failed to detect the carrier, and applies to serial WAN interfaces.

 

# Display brief information about all interfaces.

<Sysname> display interface brief

Brief information on interfaces in route mode:

Link: ADM - administratively down; Stby - standby

Protocol: (s) – spoofing

Interface            Link Protocol Primary IP         Description

InLoop0              UP   UP(s)    --

Loop0                UP   UP(s)    --

M-GE0/0/0            UP   UP       192.168.0.65

NULL0                UP   UP(s)    --

REG0                 DOWN --       -- 

Vlan1                UP   DOWN     --

Vlan999              UP   UP       192.168.1.42

 

The brief information of interfaces in bridge mode:

Link: ADM - administratively down

Speed: (a) - auto

Duplex: (a)/A - auto; H - half; F - full

Type: A - access; T - trunk; H - hybrid

Interface              Link Speed   Duplex Type PVID Description

XGE1/0/2               DOWN auto    A      A    1

XGE1/0/3               UP   10G(a)  F(a)   A    1    aaaaaaaaaaaaaaaaaaaaaaaaaaa

XGE1/0/4               DOWN auto    A      A    1

XGE1/0/5               DOWN auto    A      A    1

XGE1/0/6               UP   10G(a)  F(a)   A    1

XGE1/0/7               DOWN auto    A      A    1

XGE1/0/8               UP   10G(a)  F(a)   A    1

XGE1/0/9               UP   10G(a)  F(a)   A    999

# Display brief information about Ten-GigabitEthernet 1/0/3, including the complete interface description.

<Sysname> display interface ten-gigabitethernet 1/0/3 brief description

The brief information of interfaces in bridge mode:

Link: ADM - administratively down

Speed: (a) - auto

Duplex: (a)/A - auto; H - half; F - full

Type: A - access; T - trunk; H - hybrid

Interface              Link Speed   Duplex Type PVID Description

XGE1/0/3               UP   10G(a)  F(a)   A    1    aaaaaaaaaaaaaaaaaaaaaaaaaaaaa

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

# Display information about interfaces in DOWN state and the causes.

<Sysname> display interface brief down

Brief information on interfaces in bridge mode:

Link: ADM - administratively down; Stby - standby

Interface            Link Cause

XGE1/0/2               DOWN Not connected

XGE1/0/4               DOWN Not connected

XGE1/0/5               DOWN Not connected

XGE1/0/7               DOWN Not connected

Table 5 Command output

Field

Description

Brief information of interfaces in route mode:

Brief information about Layer 3 interfaces.

Link: ADM - administratively down; Stby - standby

·     ADM—The interface has been shut down by the network administrator. To recover its physical layer state, run the undo shutdown command.

·     Stby—The interface is a standby interface.

Protocol: (s) – spoofing

If the data link layer protocol of an interface is up, but its link is an on-demand link or not present at all, this field displays UP (s), where s represents the spoofing flag. This attribute is typical of interface Null 0 and loopback interfaces.

Interface

Interface name.

Link

Physical link state of the interface:

·     UP—The link is up.

·     DOWN—The link is physically down.

·     ADM—The link has been administratively shut down. To recover its physical state, run the undo shutdown command.

·     Stby—The interface is a standby interface.

Protocol

Link layer protocol state of the interface:

·     UP.

·     DOWN.

·     UP(s)—The link of the interface is an on-demand link or not present at all.

Primary IP

Primary IP address of the interface. A hyphen (-) indicates that the interface is not configured with an IP address.

Description

Partial or complete interface description configured by using the description command:

·     If you do not specify the description keyword for the display interface brief command, the Description field displays only the first 27 characters of the interface description.

·     If you specify the description keyword for the display interface brief command, the field displays the complete interface description.

The brief information of interfaces in bridge mode:

Brief information about Layer 2 interfaces.

Speed: (a) - auto

Duplex: (a)/A - auto; H - half; F - full

If the speed of an interface is automatically negotiated, its speed attribute includes the autonegotiation flag, indicated by the letter a in parentheses.

If the duplex mode of an interface is automatically negotiated, its duplex mode attribute includes the following options:

·     (a)/A—Autonegotiation.

·     H—Half negotiation.

·     F—Full negotiation.

Type: A - access; T - trunk; H – hybrid

Link type options for Ethernet interfaces.

Speed

Interface rate, in bps.

Duplex

Duplex mode of the interface:

·     AAutonegotiation.

·     FFull duplex.

·     F(a)Autonegotiated full duplex.

·     HHalf duplex.

·     H(a)Autonegotiated half duplex.

Type

Link type of the interface:

·     AAccess.

·     HHybrid.

·     TTrunk.

PVID

Port VLAN ID.

Cause

Cause for the physical link state of an interface to be DOWN:

·     Administratively—The port is manually shut down by using the shutdown command. To restore the physical state of the interface, use the undo shutdown command.

·     DOWN ( Link-Aggregation interface down )When an aggregate interface is shut down, the physical state of all member ports of the aggregate interface becomes DOWN.

·     DOWN (Loopback detection down)The port is shut down because the loopback detection module has detected loops.

·     DOWN ( Monitor-Link uplink down )The port is shut down because the monitor link module has detected that the uplink is down.

·     MAD ShutDownAfter an IRF split, the state of all interfaces except the excluded ports in the IRF in recovery state is set to DOWN.

·     Not connected—No physical connection exists (possibly because the network cable is disconnected or faulty).

·     Storm-ConstrainThe port is shut down because the unknown unicast traffic, multicast traffic, or broadcast traffic exceeds the upper limit.

·     STP DOWNThe port is shut down by the STP BPDU guard function.

·     Port Security Disabled—The port is shut down by the intrusion detection mechanism because the port receives illegal packets.

·     Standby—The interface is in the Standby state.

 

Related commands

reset counters interface

display packet-drop

Use display packet-drop to display information about packets dropped on an interface or multiple interfaces.

Syntax

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

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

interface-type: Specifies an interface type. If you do not specify an interface type, this command displays information about dropped packets on all the interfaces on the device.

interface-number: Specifies an interface number. If you specify an interface type only, this command displays information about dropped packets on the specified type of interfaces.

summary: Displays the summary of dropped packets on all interfaces.

Examples

# Display information about dropped packets on Ten-GigabitEthernet 1/0/1.

<Sysname> display packet-drop interface ten-gigabitethernet 1/0/1

Ten-GigabitEthernet1/0/1:

Packets dropped due to full GBP or insufficient bandwidth: 301

Packets dropped due to Fast Filter Processor (FFP): 261

Packets dropped due to STP non-forwarding state: 321

Packets dropped due to insufficient data buffer. Input dropped: 0 Output dropped: 0

# Display the summary of dropped packets on all interfaces.

<Sysname> display packet-drop summary

All interfaces:

  Packets dropped due to full GBP or insufficient bandwidth: 301

  Packets dropped due to Fast Filter Processor (FFP): 261

  Packets dropped due to STP non-forwarding state: 321

  Packets dropped due to insufficient data buffer. Input dropped: 0 Output dropped: 0

Table 6 Command output

Field

Description

Packets dropped due to full GBP or insufficient bandwidth

Packets that are dropped because the buffer is used up or the bandwidth is insufficient.

Packets dropped due to Fast Filter Processor (FFP)

Packets that are filtered out.

Packets dropped due to STP non-forwarding state

Packets that are dropped because STP is in the non-forwarding state.

Packets dropped due to insufficient data buffer. Input dropped: 0 Output dropped: 0

Packets that are dropped because of insufficient data buffer.

 

 

NOTE:

Statistics about the outgoing packets dropped due to FFP or STP are not collected.

display priority-flow-control

Use display priority-flow-control to display the PFC information and frame statistics for an interface.

Syntax

display priority-flow-control interface [ interface-type [ interface-number ] ]

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

interface-type: Specifies an interface type. If you do not specify an interface type, the command displays the PFC information and frame statistics for all Ethernet interfaces.

interface-number: Specifies an interface number. If you do not specify an interface number, the command displays the PFC information and frame statistics for all Ethernet interfaces of the specified type.

Examples

# Display the PFC information and frame statistics for all Ethernet interfaces.

<Sysname> display priority-flow-control interface

Interface           AdminMode  OperMode  Dot1pList   Prio  Recv       Send

--------------------------------------------------------------------------------

XGE1/0/1            Disabled   Disabled  0,2-3,5-6

XGE1/0/2            Auto       Enabled   0-1,3-4,6-7 0     4294967295 4294967295

                                                     5     23         0

                                                     7     5          0

XGE1/0/3            Enabled    Enabled   0-2,4-5,7   0     178        43

                                                     1     234        112

                                                     4     13         0

                                                     5     1572       0

                                                     7     110        0

XGE1/0/4            Auto       Disabled  1-2,4-5,7

Table 7 Command output

Field

Description

Interface

Abbreviated name of the interface.

AdminMode

Administrative PFC status:

·     Disabled—PFC is disabled for the interface.

·     Auto—The interface is configured to autonegotiate the PFC status with the remote end.

·     Enabled—PFC is enabled for the interface.

OperMode

Operative PFC status:

·     Disabled—PFC is disabled.

·     Enabled—PFC is enabled.

Dot1pList

802.1p priorities that are enabled with PFC. 802.1p priority values 0 through 7 are available.

Prio

An 802.1p priority is displayed only when the 802.1p priority is enabled with PFC and the interface has received or sent packets with the 802.1p priority.

Recv

Number of received frames.

Send

Number of sent frames.

 

duplex

Use duplex to set the duplex mode for an Ethernet interface.

Use undo duplex to restore the default duplex mode of the Ethernet interface.

Syntax

duplex { auto | full | half }

undo duplex

Default

Ethernet interfaces autonegotiate the duplex mode.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

auto: Configures the interface to autonegotiate the duplex mode with the peer.

full: Configures the interface to operate in full duplex mode, so that the interface can receive and transmit packets at the same time.

half: Configures the interface to operate in half duplex mode, so that the interface can only receive or transmit packets at a given time. Copper ports operating at 1000 Mbps or 10 Gbps and fiber ports do not support this keyword.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to operate in full duplex mode.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] duplex full

eee enable

IMPORTANT

IMPORTANT:

Fiber ports do not support this command.

 

Use eee enable to enable EEE.

Use undo eee enable to restore the default.

Syntax

eee enable

undo eee enable

Default

EEE is disabled.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

With the EEE function, 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 port enters the normal state.

Examples

# Enable EEE on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] eee enable

flow-control

CAUTION

CAUTION:

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

 

Use flow-control to enable TxRx mode generic flow control on an Ethernet interface.

Use undo flow-control to disable generic flow control on the Ethernet interface.

Syntax

flow-control

undo flow-control

Default

Generic flow control is disabled on an Ethernet interface.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

To implement flow control on a link, enable the generic flow control function at both ends of the link.

TxRx mode generic flow control enables an Ethernet interface to perform the following actions:

·     Receive common pause frames from its peer.

·     Send common pause frames to notify its peer of congestions.

With the flow-control command configured, an interface can both send and receive flow control frames:

·     When congested, the interface sends a flow control frame to its peer.

·     Upon receiving a flow control frame from the peer, the interface suspends sending packets.

Examples

# Enable TxRx mode generic flow control on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] flow-control

flow-control receive enable

CAUTION

CAUTION:

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

 

Use flow-control receive enable to enable Rx mode generic flow control on an Ethernet port.

Use undo flow-control to disable generic flow control on an Ethernet interface.

Syntax

flow-control receive enable

undo flow-control

Default

Rx flow control is disabled on Ethernet interfaces.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

With the flow-control receive enable command configured, an interface can receive, but not send, flow control frames. When the interface receives a flow control frame from its peer, it suspends sending packets to the peer. When traffic congestion occurs on the interface, it 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. To enable both ends of the link to handle traffic congestion, configure the flow-control command at both ends.

Examples

# Enable Rx mode generic flow control on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] flow-control receive enable

Related commands

flow-control

flow-interval

Use flow-interval to set the interface statistics polling interval.

Use undo flow-interval to restore the default interval.

Syntax

flow-interval interval

undo flow-interval

Default

The interface statistics polling interval is 300 seconds.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

interval: Sets the statistics polling interval, in seconds. The interval is in the range of 5 to 300 and must be a multiple of 5.

Examples

# Set the statistics polling interval to 100 seconds on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] flow-interval 100

interface

Use interface to enter interface view.

Syntax

interface interface-type interface-number

Views

System view

Predefined user roles

network-admin

Parameters

interface-type: Specifies an interface type.

interface-number: Specifies an interface number.

Examples

# Enter Ten-GigabitEthernet 1/0/1 interface view.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1]

jumboframe enable

Use jumboframe enable to allow jumbo frames within the specified length to pass through.

Use undo jumboframe enable to prevent jumbo frames from passing through.

Syntax

jumboframe enable [ value ]

undo jumboframe enable

Default

The device allows jumbo frames within 10000 bytes to pass through.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

value: Sets the maximum length of Ethernet frames that are allowed to pass through. The value range is 1536 to 10000 bytes.

Usage guidelines

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

Examples

# Enable jumbo frames to pass through Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] jumboframe enable

link-delay

Use link-delay to set the physical state change suppression interval on an Ethernet interface.

Use undo link-delay to restore the default.

Syntax

link-delay [ msec ] delay-time [ mode { up | updown } ]

undo link-delay

Default

Each time the physical link of a port goes up or comes down, the interface immediately reports the change to the CPU.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

msec: Enables the physical state change suppression interval to be accurate to milliseconds. If you do not specify this keyword, the suppression interval is accurate to seconds.

delay-time: Sets the physical state change suppression interval on the Ethernet interface. A value of 0 indicates that physical state changes are immediately reported to the CPU and are not suppressed.

·     If you do not specify the msec keyword, the value range for this argument is 0 to 30 seconds.

·     If you specify the msec keyword, the value range for this argument is 0 to 10000 milliseconds, and the value must be a multiple of 100.

mode up: Suppresses the link-up events.

mode updown: Suppresses both the link-up and link-down events.

Usage guidelines

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.

On a port, if you configure the link-delay command multiple times, the most recent configuration takes effect.

Do not configure this command on a port with RRPP, spanning tree protocols, or Smart Link enabled.

Examples

# Set the link-down event suppression interval to 8 seconds on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] link-delay 8

# Set the link-up event suppression interval to 800 milliseconds on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] link-delay msec 800 mode up

loopback

Use loopback to perform a loopback test on an Ethernet interface.

Syntax

loopback { external | internal }

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

external: Performs an external loopback test on the Ethernet interface.

internal: Performs an internal loopback test on the Ethernet interface.

Usage guidelines

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.

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 the loopback test is complete, the port returns to its duplex setting.

Examples

# Perform an internal loopback test on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] loopback internal

Loop internal succeeded!

multicast-suppression

Use multicast-suppression to enable multicast storm suppression and set the multicast storm suppression threshold.

Use undo multicast-suppression to restore the default.

Syntax

multicast-suppression { ratio | pps max-pps | kbps max-kbps } [ unknown ]

undo multicast-suppression

Default

Ethernet interfaces do not suppress multicast traffic.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

ratio: Sets the multicast suppression threshold as a percentage of the interface bandwidth. The value range for this argument (in percentage) is 0 to 100. A smaller value means that less multicast traffic is allowed to pass through.

pps max-pps: Specifies the maximum number of multicast packets that the interface can forward per second. The value range for the max-pps argument (in pps) is 0 to 1.4881 × the interface bandwidth. For example, the value range of the max-pps argument for a 40-GE interface is 0 to 59524000.

kbps max-kbps: Specifies the maximum number of kilobits of multicast traffic that the Ethernet interface can forward per second. The value range for this argument (in kbps) is 0 to the interface bandwidth.

unknown: Suppresses only the unknown multicast traffic.

Usage guidelines

The multicast storm suppression feature limits the size of multicast traffic (including known and unknown multicast) to a threshold on an interface. When the multicast traffic on the interface exceeds this threshold, the system drops packets until the traffic drops below this threshold.

Both storm-constrain and multicast-suppression can suppress multicast storm on a port. The multicast-suppression command uses the chip to physically suppress multicast traffic. It has less influence on the device performance than the storm-constrain command, which uses software to suppress multicast traffic.

For the traffic suppression result to be determined, do not configure both the storm constrain multicast command and the multicast-suppression command on an 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 device.

Examples

# Set the multicast storm suppression threshold to 10000 kbps on Ten-GigabitEthernet1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] multicast-suppression kbps 10000

The actual value is 10048 on port Ten-GigabitEthernet1/0/1 currently.

Related commands

·     broadcast-suppression

·     unicast-suppression

port auto-power-down

IMPORTANT

IMPORTANT:

Fiber ports do not support this command.

 

Use port auto-power-down to enable auto power-down on an Ethernet interface.

Use undo port auto-power-down to restore the default.

Syntax

port auto-power-down

undo port auto-power-down

Default

Auto power-down is disabled on Ethernet interfaces.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

When the auto power-down function 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 the power supply to the interface.

·     The interface enters its normal state.

Examples

# Enable auto power-down on Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] port auto-power-down

port up-mode

Use port up-mode to forcibly bring up a fiber port.

Use undo port up-mode to restore the default.

Syntax

port up-mode

undo port up-mode

Default

Fiber ports are not forcibly brought up. The physical state of the fiber port is determined by the physical state of the optical fibers.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

CAUTION

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.

 

You can use this command to forcibly bring up a fiber Ethernet port, and enable the port to forward packets unidirectionally over a single link. In this way, transmission links are well utilized.

After you forcibly bring up an Ethernet fiber port, the fiber port stays physically up whether or not a transceiver module or fiber connections are present for the port.

Copper ports do not support this command.

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

Examples

# Forcibly bring up fiber port Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] port up-mode

priority-flow-control

Use priority-flow-control to enable PFC on an Ethernet interface through automatic negotiation or forcibly.

Use undo priority-flow-control to disable PFC on the interface.

Syntax

priority-flow-control { auto | enable }

undo priority-flow-control

Default

PFC is disabled on Ethernet interfaces.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

auto: Specifies PFC in auto mode. In this mode, the Ethernet interface automatically negotiates the PFC status with its peer.

enable: Forcibly enables PFC.

Usage guidelines

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.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to automatically negotiate with its peer to enable PFC.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] priority-flow-control auto

Related commands

priority-flow-control no-drop dot1p

priority-flow-control no-drop dot1p

Use priority-flow-control no-drop dot1p to enable PFC for 802.1p priorities on an Ethernet interface.

Use undo priority-flow-control no-drop dot1p to restore the default.

Syntax

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

undo priority-flow-control no-drop dot1p

Default

PFC is disabled for all 802.1p priorities.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

dot1p-list: Specifies an 802.1p priority (or dot1p priority) list to identify flows that are subject to PFC(for example: 1,3-5). A hyphen (-) connects two numeric values, which together indicate a continuous value range. Different values or value ranges are separated with commas (,). You can configure up to 16 characters for this argument.

Usage guidelines

You can enable PFC for certain 802.1p priorities at the two ends of a link. When network congestion occurs, the local device checks the PFC status for the 802.1p priority carried in each arriving packet. The device processes the packet depending on the PFC status as follows:

·     If PFC is enabled for the 802.1p priority, the local device accepts the packet and sends a PFC pause frame to the peer. The peer stops sending packets carrying this 802.1p priority for an interval as specified in the PFC pause frame. This process is repeated until the congestion is removed.

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

The relationship between the PFC function and the generic flow control function is shown in Table 8.

Table 8 The relationship between the PFC function and the generic flow control function

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.

 

When you configure PFC, follow these guidelines:

·     As a best practice to ensure correct operations of IRF and other protocols, do not enable PFC for 802.1p priorities 0, 6, and 7.

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

For more information about the 802.1p priority, priority trust mode, and port priority, see ACL and QoS Configuration Guide.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to automatically negotiate with the peer port to enable PFC, and enable PFC for 802.1p priority 5.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] priority-flow-control auto

[Sysname-Ten-GigabitEthernet1/0/1] priority-flow-control no-drop dot1p 5

Related commands

·     priority-flow-control

·     flow-control

·     flow-control receive enable

reset counters interface

Use reset counters interface to clear the Ethernet interface statistics.

Syntax

reset counters interface [ interface-type [ interface-number ] ]

Views

User view

Predefined user roles

network-admin

Parameters

interface-type: Specifies an interface type.

interface-number: Specifies an interface number.

Usage guidelines

Use this command to clear history statistics if you want to collect traffic statistics for a specific time period.

If you do not specify an interface type, this command clears statistics for all interfaces.

If you specify only the interface type, this command clears statistics for all interfaces of that type.

If you specify both the interface type and the interface number, this command clears statistics for the specified interface.

Examples

# Clear the statistics of Ten-GigabitEthernet 1/0/1.

<Sysname> reset counters interface ten-gigabitethernet 1/0/1

Related commands

·     display interface

·     display counters interface

·     display counters rate interface

reset ethernet statistics

Use reset ethernet statistics to clear the Ethernet module statistics.

Syntax

reset ethernet statistics slot slot-number

Views

User view

Predefined user roles

network-admin

network-operator

Parameters

slot slot-number: Clears the Ethernet module statistics on the specified device. The slot-number argument specifies the IRF member device by its member ID.

Examples

# Clear the Ethernet module statistics on IRF member 6.

<Sysname> reset ethernet statistics slot 6

reset packet-drop interface

Use reset packet-drop interface to clear the dropped packet statistics on an interface or multiple interfaces.

Syntax

reset packet-drop interface [ interface-type [ interface-number ] ]

Views

User view

Predefined user roles

network-admin

Parameters

interface-type: Specifies an interface type. If you do not specify an interface type, this command clears dropped packet statistics on all the interfaces on the device.

interface-number: Specifies an interface number. If you do not specify this argument, the command clears dropped packet statistics on all interfaces of the specified type.

Examples

# Clear dropped packet statistics on Ten-GigabitEthernet 1/0/1.

<Sysname> reset packet-drop interface ten-gigabitethernet 1/0/1

# Clear dropped packet statistics on all interfaces.

<Sysname> reset packet-drop interface

Related commands

display packet-drop

shutdown

Use shutdown to shut down an Ethernet interface.

Use undo shutdown to bring up an Ethernet interface.

Syntax

shutdown

undo shutdown

Default

Ethernet interfaces are in up state.

Views

Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

You might need to shut down and then bring up an Ethernet interface to make some interface configurations take effect.

Examples

# Shut down and then bring up Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] shutdown

[Sysname-Ten-GigabitEthernet1/0/1] undo shutdown

speed

Use speed to set the speed of an Ethernet interface.

Use undo speed to restore the default.

Syntax

speed { 1000 | 10000 | 40000 | auto }

undo speed

Default

An Ethernet interface negotiates a speed with its peer.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

1000: Sets the interface speed to 1000 Mbps.

10000: Sets the interface speed to 10000 Mbps.

40000: Sets the interface speed to 40000 Mbps.

auto: Enables the interface to negotiate a speed with its peer.

Usage guidelines

For an Ethernet copper port, use the speed command to set its speed to match the speed of the peer interface.

For a fiber port, use the speed command to set its speed to match the rate of a transceiver module.

Support of an interface for the keywords depends on the interface type. For more information, use the speed ? command in interface view.

In auto mode, Ethernet interfaces do not support negotiating a speed of 10 Mbps or 100 Mbps.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to autonegotiate the speed.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] speed auto

Related commands

speed auto

unicast-suppression

Use unicast-suppression to enable unknown unicast storm suppression and set the unknown unicast storm suppression threshold.

Use undo unicast-suppression to restore the default.

Syntax

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

undo unicast-suppression

Default

Ethernet interfaces do not suppress unknown unicast traffic.

Views

Ethernet interface view

Predefined user roles

network-admin

Parameters

ratio: Sets the unknown unicast suppression threshold as a percentage of the interface bandwidth. The value range for this argument (in percentage) is 0 to 100. A smaller value means that less unknown unicast traffic is allowed to pass through.

pps max-pps: Specifies the maximum number of unknown unicast packets that the interface can forward per second. The value range for the max-pps argument (in pps) is 0 to 1.4881 × the interface bandwidth. For example, the value range of the max-pps argument for a 40-GE interface is 0 to 59524000.

kbps max-kbps: Specifies the maximum number of kilobits of unknown unicast traffic that the Ethernet interface can forward per second. The value range for this argument (in kbps) is 0 to the interface bandwidth.

Usage guidelines

The unknown unicast storm suppression feature limits the size of unknown unicast traffic to a threshold on an interface. When the unknown unicast traffic on the interface exceeds this threshold, the system drops packets until the traffic drops below this threshold.

Both storm-constrain and unicast-suppression can suppress unknown unicast storm on a port. The unicast-suppression command uses the chip to physically suppress unknown unicast traffic. It has less influence on the device performance than the storm-constrain command, which uses software to suppress unknown unicast traffic.

For the traffic suppression result to be determined, do not configure both the storm constrain unicast command and the unicast-suppression command on an 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 device.

Examples

# Set the unknown unicast storm suppression threshold to 10000 kbps on Ten-GigabitEthernet1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] unicast-suppression kbps 10000

The actual value is 10048 on port Ten-GigabitEthernet1/0/1 currently.

Related commands

·     broadcast-suppression

·     multicast-suppression

using fortygige

Use using fortygige to combine four 10-GE breakout interfaces that are split from a 40-GE interface into a 40-GE interface.

Use undo using fortygige to cancel the configuration.

Syntax

using fortygige

undo using fortygige

Default

A 40-GE interface is not split and operates as a single interface.

Views

10-GE breakout interface view

Predefined user roles

network-admin

Usage guidelines

If you need higher bandwidth, you can combine four 10-GE breakout interfaces that are split from a 40-GE interface into a 40-GE interface. To make this command take effect on the four 10-GE breakout interfaces, execute this command on only one of the 10-GE breakout interfaces.

After this command is successfully configured, the system prompts you to reboot your device. You must reboot the device and then the system deletes the four 10-GE breakout interface and creates the combined 40-GE interface.

Examples

# Combine 10-GE breakout interfaces Ten-GigabitEthernet 1/0/16:1 through Ten-GigabitEthernet 1/0/16:4 into a 40-GE interface.

<System> system-view

[System] interface Ten-GigabitEthernet1/0/16:1

[System-Ten-GigabitEthernet1/0/16:1] using fortygige

The interfaces Ten-GigabitEthernet1/0/16:1 through Ten-GigabitEthernet1/0/16:4 will be deleted. Continue? [Y/N]:y

Reboot the member device to make the configuration take effect.

Related commands

using tengige

using tengige

Use using tengige to split a high-bandwidth interface into multiple 10-GE breakout interfaces.

Use undo using tengige to cancel the configuration.

Syntax

using tengige

undo using tengige

Default

A high-bandwidth interface is not split and operates as a single interface.

Views

40-GE interface view

Predefined user roles

network-admin

Usage guidelines

To improve the port density, reduce the cost, and improve the network flexibility, you can split a high-bandwidth interface into multiple 10-GE breakout interfaces.

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

After this command is successfully configured, the system prompts you to reboot your device. You must reboot the device and then the system deletes the 40-GE interface and creates four 10-GE breakout interfaces.

Examples

# Split 40-GE interface FortyGigE 1/0/16 into four 10-GE breakout interfaces.

<System> system-view

[System] interface fortygige 1/0/16

[System-FortyGigE1/0/16] using tengige

The interface FortyGigE1/0/16 will be deleted. Continue? [Y/N]:y

Reboot the member device to make the configuration take effect.

Related commands

using fortygige

Layer 2 Ethernet interface commands

display storm-constrain

Use display storm-constrain to display storm control settings and statistics.

Syntax

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

Views

Any view

Predefined user roles

network-admin

network-operator

Parameters

broadcast: Displays broadcast storm control settings and statistics.

multicast: Displays multicast storm control settings and statistics.

unicast: Displays unknown unicast storm control settings and statistics.

interface interface-type interface-number: Specifies an interface by its type and number.

Usage guidelines

If you do not specify any keywords, this command displays all storm control settings on all storm control-enabled interfaces.

Examples

# Display the storm control settings on all storm control-enabled ports.

<Sysname> display storm-constrain

Abbreviation: BC - broadcast; MC - multicast; UC – unicast

               FW - forwarding

Flow Statistic Interval: 5 (in seconds)

Port       Type  Lower   Upper     Unit   CtrlMode  Status     Trap  Log  SwitchNum

-------------------------------------------------------------------------------------

XGE1/0/1    BC   12345   3456      pps    block     FW          on   off   0

XGE1/0/2    MC   43      100       ratio  block     block       on   off   1

XGE1/0/3    MC   100     200       kbps   shutdown  shutdown    off  on    10

XGE1/0/4    UC   200     300       kbps   shutdown  normal      off  on    33

XGE1/0/5    BC   500     1500      pps    N/A       normal      on   on    0

Table 9 Command output

Field

Description

Flow Statistic Interval

Traffic polling interval (in seconds) of the storm control module.

Port

Abbreviated port name.

Type

Type of traffic subjected to storm control:

·     BC—Broadcast packets.

·     MC—Multicast packets.

·     UC—Unknown unicast packets.

Lower

Lower storm control threshold, in pps, kbps, or percentage.

Upper

Upper storm control threshold, in pps, kbps, or percentage.

Unit

Storm control threshold unit:

·     pps.

·     kbps.

·     percentage.

CtrlMode

Protective action (block or shutdown) taken on the port when the upper threshold is reached. N/A indicates that no protective action is configured.

Status

Packet forwarding status:

·     FW—The port is forwarding traffic correctly.

·     shutdown—The port has been shut down.

·     block—The port drops the type of traffic.

Trap

Status of the storm control threshold event trap switch:

·     on—The port sends threshold event traps.

·     off—The port does not send threshold event traps.

Log

Status of the storm control threshold event log switch:

·     on—The port sends threshold event log messages.

·     off—The port does not send threshold event log messages.

SwitchNum

Number of forwarding state changes of the interface.

When the SwitchNum count reaches 65535, it resets automatically.

 

mdix-mode

IMPORTANT

IMPORTANT:

·     Fiber ports do not support this command.

·     10-GE copper ports support only the automdix mode.

 

Use mdix-mode to configure the Medium Dependent Interface Cross-Over (MDIX) mode of an Ethernet interface.

Use undo mdix-mode to restore the default.

Syntax

mdix-mode { automdix | mdi | mdix }

undo mdix-mode

Default

Ethernet interfaces operate in automdix mode.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Parameters

automdix: Specifies that the interface negotiates pin roles with its peer.

mdi: Specifies that pins 1 and 2 are transmit pins and pins 3 and 6 are receive pins.

mdix: Specifies that pins 1 and 2 are receive pins and pins 3 and 6 are transmit pins.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to operate in automdix mode.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] mdix-mode automdix

port bridge enable

Use port bridge enable to enable bridging on a Layer 2 Ethernet interface.

Use undo port bridge enable to disable bridging on a Layer 2 Ethernet interface.

Syntax

port bridge enable

undo port bridge enable

Default

Bridging is disabled on Layer 2 Ethernet interfaces.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

When a packet arrives at an interface, the device 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 device drops the packet.

After you configure this command on the Ethernet interface, the device forwards such packets rather than drop them.

Examples

# Enable bridging on Layer 2 Ethernet interface Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] port bridge enable

port connection-distance

Use port connection-distance to set the interface connection distance.

Use undo port connection-distance to restore the default.

Syntax

port connection-distance { 300 | 10000 | 20000 | 40000 }

undo port connection-distance

Default

The interface connection distance is 10000 meters.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Parameters

300: Sets the interface connection distance to 300 meters.

10000: Sets the interface connection distance to 10000 meters.

20000: Sets the interface connection distance to 20000 meters.

40000: Sets the interface connection distance to 40000 meters.

Usage guidelines

When two directly connected interfaces communicate, they use the buffer area to buffer the received data. A longer interface connection distance requires a greater buffer area.

Perform this task to modify the buffer area size by setting the interface connection distance.

Configure this command based on the network conditions because the buffer area size is limited.

Examples

# Set the interface connection distance to 20000 meters.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] port connection-distance 20000

storm-constrain

Use storm-constrain to enable broadcast, multicast, or unknown unicast storm control on an Ethernet port.

Use undo storm-constrain to disable storm control.

Syntax

storm-constrain { broadcast | multicast | unicast } { pps | kbps | ratio } upperlimit lowerlimit

undo storm-constrain { all | broadcast | multicast | unicast }

Default

Traffic storm control is disabled.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Parameters

all: Disables storm control for all types of packets: broadcast, multicast, and unknown unicast.

broadcast: Enables or disables broadcast storm control.

multicast: Enables or disables multicast storm control.

unicast: Enables or disables unknown unicast storm control.

pps: Sets storm control thresholds in pps.

kbps: Sets storm control thresholds in kbps.

ratio: Sets storm control thresholds as a percentage of the transmission capacity of the interface.

upperlimit: Sets the upper threshold, in pps, kbps, or percentage.

lowerlimit: Sets the lower threshold, in pps, kbps, or percentage.

Usage guidelines

After you configure this command, the device collects the statistics of a particular type of traffic at the specified interval, which can be configured by using the storm-constrain interval command. When a particular type of traffic exceeds its upper threshold, the interface takes a certain action, which can be configured by using the storm-constrain control command.

The storm-constrain, broadcast-suppression, multicast-suppression, and unicast-suppression commands can suppress storm on a port.

·     The storm-constrain command uses software to suppress traffic, and affects the device performance to a certain extent.

·     The broadcast-suppression, multicast-suppression, and unicast-suppression commands use the chip to physically suppress traffic, and have less influence on the device performance than the storm-constrain command.

On the same type of traffic, do not configure the storm constrain command and either of the broadcast-suppression, multicast-suppression, and unicast-suppression commands at the same time. Otherwise, the traffic suppression result is not determined.

When configuring this command, make sure upperlimit is greater than lowerlimit.

Examples

# Enable unknown unicast storm control on Ten-GigabitEthernet 1/0/1, setting the upper and lower thresholds to 200 pps and 150 pps.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] storm-constrain unicast pps 200 150

# Enable broadcast storm control on Ten-GigabitEthernet 1/0/2, setting the upper and lower thresholds to 2000 kbps and 1500 kbps.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/2

[Sysname-Ten-GigabitEthernet1/0/2] storm-constrain broadcast kbps 2000 1500

# Enable multicast storm control on Ten-GigabitEthernet 1/0/3, setting the upper and lower thresholds to 80% and 15%.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/3

[Sysname-Ten-GigabitEthernet1/0/3] storm-constrain multicast ratio 80 15

Related commands

·     storm-constrain control

·     storm-constrain interval

storm-constrain control

Use storm-constrain control to set the protective action to take on an Ethernet interface when a type of traffic (unknown unicast, multicast, or broadcast) exceeds the upper storm control threshold.

Use undo storm-constrain control to restore the default.

Syntax

storm-constrain control { block | shutdown }

undo storm-constrain control

Default

No action is taken on an Ethernet interface when a type of traffic exceeds the upper storm control threshold.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Parameters

block: 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 is detected dropping below the lower threshold, the port begins to forward the traffic.

shutdown: Shuts down automatically. The interface shuts 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 function.

Examples

# Configure Ten-GigabitEthernet 1/0/1 to block the traffic detected crossing the upper storm control threshold.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] storm-constrain control block

Related commands

·     storm-constrain

·     storm-constrain control

storm-constrain enable log

Use storm-constrain enable log to enable an Ethernet interface to log storm control threshold events.

Use undo storm-constrain enable log to disable log sending.

Syntax

storm-constrain enable log

undo storm-constrain enable log

Default

An interface generates logs when monitored traffic exceeds the upper threshold or falls below the lower threshold.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Examples

# Enable Ten-GigabitEthernet 1/0/1 to generate logs when it detects storm control threshold events.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] storm-constrain enable log

storm-constrain enable trap

Use storm-constrain enable trap to enable an Ethernet interface to send storm control threshold event traps.

Use undo storm-constrain enable trap to disable trap sending.

Syntax

storm-constrain enable trap

undo storm-constrain enable trap

Default

An interface sends out traps when monitored traffic exceeds the upper threshold or falls below the lower threshold.

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Examples

# Enable Ten-GigabitEthernet 1/0/1 to send traps when it detects storm control threshold events.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] storm-constrain enable trap

storm-constrain interval

Use storm-constrain interval to set the traffic polling interval of the storm control module.

Use undo storm-constrain interval to restore the default.

Syntax

storm-constrain interval seconds

undo storm-constrain interval

Default

The storm control module polls traffic statistics every 10 seconds.

Views

System view

Predefined user roles

network-admin

Parameters

seconds: Sets the traffic polling interval of the storm control module. The value range is 1 to 300 seconds.

Usage guidelines

The interval set by the storm-constrain interval command is specific to storm control. To set the statistics polling interval of an interface, use the flow-interval command.

For network stability, use the default or a higher polling interval.

Examples

# Set the traffic statistics polling interval of the storm control module to 60 seconds.

<Sysname> system-view

[Sysname] storm-constrain interval 60

Related commands

·     storm-constrain

·     storm-constrain control

virtual-cable-test

IMPORTANT

IMPORTANT:

Fiber ports do not support this command.

 

Use virtual-cable-test to test the cable connection of an Ethernet interface and display the test results.

Syntax

virtual-cable-test

Views

Layer 2 Ethernet interface view

Predefined user roles

network-admin

Usage guidelines

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

The test result is for reference only. The cable length detection error is up to 5 m (about 16 ft).

If a test item is not available, a hyphen (-) is displayed.

Examples

# Test the cable connection of Ten-GigabitEthernet 1/0/1.

<Sysname> system-view

[Sysname] interface ten-gigabitethernet 1/0/1

[Sysname-Ten-GigabitEthernet1/0/1] virtual-cable-test

Cable status: abnormal(open), 140 metre(s)

Pair Impedance mismatch: -

Pair skew: - ns

Pair swap: -

Pair polarity: -

Insertion loss: - db

Return loss: - db

Near-end crosstalk: - db

Table 10 Command output

Field

Description

Cable status

Cable status:

·     Normal—The cable is in good condition.

·     Abnormal—The cable is abnormal.

·     Abnormal (open)—An open circuit is detected.

·     Abnormal (short)—A short circuit is detected.

·     Failure—The test failed.

n metres

If the cable connection is working correctly, this field displays the total length of the cable.

If the cable connection fails, this field displays the length from the local port to the faulty point.