D Commands

description (interface)

To add a description to an interface configuration, use the description command. To remove the description, use the no form of this command.

description description

no description

Syntax Description

description

String description of the interface configuration. This string is limited to 80 characters.

Command Default

No description is added.

Command Modes

Interface configuration mode

Subinterface configuration mode

Virtual Ethernet interface configuration

Command History

Release

Modification

4.0(0)N1(1a)

This command was introduced.

5.0(3)N1(1)

Support for Layer 3 interfaces and virtual Ethernet interface was added.

5.1(3)N1(1)

Support for virtual Ethernet interface was added.

Usage Guidelines

The description command is meant to provide a reminder in the configuration to describe what certain interfaces are used for. The description appears in the output of the following commands such as show interface and show running-config .

You can use this command on the following interfaces:

  • Ethernet interface
  • Management interface
  • Subinterfaces
  • Virtual Ethernet interface

Examples

This example shows how to add a description for an interface: 


switch# configure terminal
switch(config)# interface ethernet 1/1
switch(config-if)# description "10G Server Link"
switch(config-if)#

This example shows how to add a description for a virtual Ethernet interface: 


switch# configure terminal
switch(config)# interface vethernet 1
switch(config-if)# description "Virtual interface"
switch(config-if)#

Related Commands

Command

Description

show interface ethernet

Displays the interface configuration information.

show interface vethernet

Displays the virtual Ethernet interface configuration information.

show running-config

Displays the contents of the currently running configuration file.

description (SPAN, ERSPAN)

To add a description to an Ethernet Switched Port Analyzer (SPAN) or an Encapsulated Remote Switched Port Analyzer (ERSPAN) session configuration, use the description command. To remove the description, use the no form of this command.

description description

no description

Syntax Description

description

String description of the SPAN session configuration. This string is limited to 80 characters.

Command Default

No description is added.

Command Modes

SPAN session configuration mode

ERSPAN session configuration mode

Command History

Release

Modification

4.0(0)N1(1a)

This command was introduced.

5.1(3)N1(1)

Support for ERSPAN was added.

Usage Guidelines

Use the description command to provide a reminder in the configuration to describe what certain SPAN sessions are used for. The description appears in the output of the following commands such as show monitor session and show running-config monitor .

Examples

This example shows how to add a description for a SPAN session: 


switch# configure terminal
switch(config)# monitor session 9 type local
switch(config-monitor)# description A Local SPAN session
switch(config-monitor)#

This example shows how to add a description for an ERSPAN session: 


switch# configure terminal
switch(config)# monitor session 9 type erspan-source
switch(config-erspan-src)# description An ERSPAN session
switch(config-erspan-src)#

Related Commands

Command

Description

destination (SPAN session)

Configures a destination SPAN port.

monitor session

Creates a new SPAN session configuration.

show monitor session

Displays SPAN session configuration information.

show running-config monitor

Displays the running configuration information of a SPAN session.

source (SPAN session)

Configures a source SPAN port.

destination (ERSPAN)

To configure an Encapsulated Remote Switched Port Analyzer (ERSPAN) destination IP address, use the destination command. To remove the destination ERSPAN IP address, use the no form of this command.

destination ip ip_address

no destination ip ip_address

Syntax Description

ip

Configures the remote IP address.

ip_address

IPv4 address in the format A .B .C .D .

Command Default

None

Command Modes

ERSPAN session configuration mode

Command History

Release

Modification

5.1(3)N1(1)

This command was introduced.

Usage Guidelines

You can configure only one destination IP address for an ERSPAN source session.

This command does not require a license.

Examples

This example shows how to configure an ERSPAN destination IP address: 


switch# configure terminal
switch(config)# monitor session 1 type erspan-source
switch(config-erspan-src)# destination ip 192.0.3.1
switch(config-erspan-src)#

Related Commands

Command

Description

monitor session

Creates a new SPAN session configuration.

show monitor session

Displays SPAN session configuration information.

show running-config monitor

Displays the running configuration information of a SPAN session.

source (SPAN session)

Configures a source SPAN port.

source (ERSPAN session)

Configures a source VLAN or VSAN interface.

destination (SPAN session)

To configure a Switched Port Analyzer (SPAN) destination port, use the destination command. To remove the destination SPAN port, use the no form of this command.

description description
no description

Syntax Description

interface

Specifies the interface type to use as the destination SPAN port.

ethernet slot /port

Specifies the Ethernet interface to use as the destination SPAN port. The slot number is from 1 to 255 and the port number is from 1 to 128.

port-channel channel-num

Specifies the EtherChannel interface to use as the destination SPAN port. The EtherChannel number is from 1 to 4096.

vlan vlan-num

Specifies the VLAN inteface to use as the destination SPAN port. The range is from 1 to 3967 and 4048 to 4093.

vsan vsan-num

Specifies the virtual storage area network (VSAN) to use as the destination SPAN port. The range is from 1 to 4093.

Command Default

None

Command Modes


SPAN session configuration mode

Command History

Release

Modification

4.0(0)N1(1a)

This command was introduced.

Usage Guidelines

Each local SPAN session destination session must have a destination port (also called a monitoring port ) that receives a copy of traffic from the source port.

The destination port can be any Ethernet physical port and must reside on the same switch as the source port (for a local SPAN session). The destination port cannot be a source port, a port channel, or SAN port channel group.

A destination port receives copies of sent and received traffic for all monitored source ports. If a destination port is oversubscribed, it can become congested. This congestion can affect traffic forwarding on one or more of the source ports.

Examples

This example shows how to configure an Ethernet interface SPAN destination port and activate the SPAN session: 


switch# configure terminal
switch(config)# interface ethernet 1/5
switch(config-if)# switchport monitor
switch(config-if)# exit
 
switch(config)# monitor session 9 type local
switch(config-monitor)# description A Local SPAN session
switch(config-monitor)# source interface ethernet 1/1
switch(config-monitor)# destination interface ethernet 1/5
switch(config-monitor)# no shutdown
switch(config-monitor)#

Related Commands

Command

Description

source (SPAN session)

Configures a source SPAN port.

monitor session

Creates a new SPAN session configuration.

show monitor session

Displays SPAN session configuration information.

show running-config monitor

Displays the running configuration information of a SPAN session.

duplex

To specify the duplex mode as full, half, or autonegotiate, use the duplex command. To return the system to default mode, use the no form of this command.

duplex { full | half | auto }

no duplex { full | half | auto }

Syntax Description

full

Specifies the duplex mode as full.

half

Specifies the duplex mode as half.

Note 
This keyword is not supported on a management interface.

auto

Specifies the duplex mode as autonegotiate.

Command Default

None

Command Modes


Interface configuration mode


network-adminvdc-admin

Command History

Release

Modification

5.1(3)N1(1)

This command was introduced.

Usage Guidelines

The interface speed that you specify can affect the duplex mode used for an interface, so you should set the speed before setting the duplex mode. If you set the speed for autonegotiation, the duplex mode is automatically set to be autonegotiated. If you specify 10- or 100-Mbps speed, the port is automatically configured to use half-duplex mode, but you can specify full-duplex mode instead. Gigabit Ethernet is full duplex only. You cannot change the duplex mode on Gigabit Ethernet ports or on a 10/100/1000-Mbps port that is set for Gigabit Ethernet.

See the Cisco Nexus 5000 Series NX-OS Layer 2 Switching Configuration Guide for more information on interface speed and duplex settings.

This command does not require a license.

Examples

This example shows how to specify the duplex mode for full duplex: 


switch# configure terminal
switch(config)# interface ethernet 1/5
switch(config-if)# duplex full
switch(config-if)#

Related Commands

Command

Description

show interface

Displays information about the interface, which includes the duplex parameter.

dvs-name

To configure the Distributed Virtual Switch (DVS) name in the vCenter Server, use the dvs-name command.

dvs-name name [name]

Syntax Description

name

DVS name. The name can be a maximum of 80 alphanumeric characters.

Command Default

None

Command Modes


SVS connection configuration mode

Command History

Release

Modification

5.1(3)N1(1)

This command was introduced.

Usage Guidelines

This command does not require a license.

Examples

This example shows how to configure the DVS name in the vCenter Server: 


switch# configure terminal
switch(config)# svs connection SVSConn
switch(config-svs-conn)# dvs-name vcWest
switch(config-svs-conn)#

Related Commands

Command

Description

show svs connections

Displays SVS connection information.

svs connection

Enables an SVS connection.

default shutdown (virtual Ethernet interface)

To enable default commands on a virtual Ethernet interface, use the default shutdown command. To disable default commands, use the no form of this command.

default shutdown

no default shutdown

Syntax Description

This command has no arguments or keywords.

Command Default

No description is added.

Command Modes


Virtual Ethernet interface configuration

Command History

Release

Modification

5.1(3)N1(1)

Support for virtual Ethernet interface was added.

Usage Guidelines

This command does not require a license.

Examples

This example shows how to enable a virtual Ethernet interface: 


switch# configure terminal
switch(config)# interface vethernet 1
switch(config-if)# default shutdown
switch(config-if)#

Related Commands

Command

Description

show interface vethernet

Displays the virtual Ethernet interface configuration information.

show running-config

Displays the contents of the currently running configuration file.

delay (interface)

To set a delay value for an interface, use the delay command. To restore the default delay value, use the no form of this command.

delay tens-of-microseconds

no delay

Syntax Description

tens-of-microseconds

Throughput delay in tens of microseconds. The range is from 1 to 16,777,215.

Command Default

10 microseconds

Command Modes


Interface configuration mode

Subinterface configuration mode

Command History

Release

Modification

4.0(0)N1(1a)

This command was introduced.

5.0(3)N1(1)

Support for Layer 3 interfaces was added.

Examples

This example shows how to set a delay of 30,000 microseconds on an interface: 


switch(config)# interface ethernet 1/1
switch(config-if)# delay 30000
switch(config-if)#

This example shows how to set a delay of 1000 microseconds on a subinterface: 


switch(config)# interface ethernet 1/1.1
switch(config-subif)# delay 1000
switch(config-subif)#

Related Commands

Command

Description

interface ethernet (Layer 3)

Configures an Ethernet routed interface.

show interface

Displays the interface configuration information.