interface These commands are used to display or set communication parameters for an Ethernet port, aggregated link, or VLAN.
Use this command to configure an interface type and enter interface configuration mode.
Syntax
interface interface
- interface
- ethernet unit/port
- unit - This is device 1.
- port - Port number.
- port-channel channel-id (Range: 1-2)
- vlan vlan-id (Range: 1-4094)
Default Setting
None
Command Mode
Global Configuration
Example
To specify the first Ethernet port, enter the following command:
(config)#interface ethernet 1/1
(config-if)#
Use this command to disable an interface. To restart a disabled interface, use the no form.
Syntax
shutdown
no shutdown
Default Setting
All interfaces are enabled.
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
This command allows you to disable a port due to abnormal behavior (e.g., excessive collisions), and then re-enable it after the problem has been resolved. You may also want to disable a port for security reasons.
Example
The following example disables Ethernet port 7.
(config)#interface ethernet 1/7
(config-if)#shutdown
(config-if)#
Use this command to clear statistics on an interface.
Syntax
clear counters interface
- interface
- ethernet unit/port
- unit - This is device 1.
- port - Port number.
Default Setting
None
Command Mode
Privileged Exec
Example
The following example clears statistics on Ethernet port 7.
#clear counters ethernet 1/7
#
Use this command to add a description to an interface. Use the no form to remove the description.
Syntax
description string
no description
string - Comment or a description to help you remember what is attached to this interface.
(Range: 1-64 characters)
Default Setting
None
Command Mode
Interface Configuration (Ethernet, Port Channel)
Example
The following example adds a description to Ethernet port 7.
(config)#interface ethernet 1/7
(config-if)#description RD SW#3
(config-if)#
Use this command to configure the speed and duplex mode of a given interface when auto-negotiation is disabled. Use the no form to restore the default.
Syntax
speed-duplex {1000full | 100full | 100half | 10full | 10half}
no speed-duplex
- 1000full - Forces 1000 Mbps full-duplex operation
- 100full - Forces 100 Mbps full-duplex operation
- 100half - Forces 100 Mbps half-duplex operation
- 10full - Forces 10 Mbps full-duplex operation
- 10half - Forces 10 Mbps half-duplex operation
Default Setting
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
Example
The following example configures port 7 to 100 Mbps, half-duplex operation.
(config)#interface ethernet 1/7
(config-if)#speed-duplex 100half
(config-if)#no negotiation
(config-if)#
Related Commands
Use this command to enable auto-negotiation for a given interface. Use the no form to disable auto-negotiation.
Syntax
negotiation
no negotiation
Default Setting
Enabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
If auto-negotiation is disabled, auto-MDI/MDI-X pin signal configuration will also be disabled for the uplink ports.
Example
The following example configures port 7 to use auto-negotiation.
(config)#interface ethernet 1/7
(config-if)#negotiation
(config-if)#
Use this command to advertise the port capabilities of a given interface during auto-negotiation. Use the no form with parameters to remove an advertised capability, or the no form without parameters to restore the default values.
Syntax
capabilities {1000full | 100full | 100half | 10full | 10half | flowcontrol | symmetric}
no port-capabilities [1000full | 100full | 100half | 10full | 10half | flowcontrol | symmetric]
- 1000full - Supports 1000 Mbps full-duplex operation
- 100full - Supports 100 Mbps full-duplex operation
- 100half - Supports 100 Mbps half-duplex operation
- 10full - Supports 10 Mbps full-duplex operation
- 10half - Supports 10 Mbps half-duplex operation
- flowcontrol - Supports flow control
- symmetric - Transmits and receives pause frames for flow control (Gigabit ports only)
Default Setting
The default values for Fast Ethernet include 10half, 10full, 100half, 100full and flow control. The default values for Gigabit Ethernet include all settings.
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
Ports 1 - 6 only support the 1000full option.
Example
The following example sets the advertised capabilities of port 7 to 100half, 100full and flow control.
(config)#interface ethernet 1/7
(config-if)#capabilities 100half
(config-if)#capabilities 100full
(config-if)#capabilities flowcontrol
(config-if)#
Use this command to enable flow control. Use the no form to disable flow control.
Syntax
flowcontrol
no flowcontrol
Default Setting
Flow control enabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
To force operation to the mode specified in a flowcontrol command, use the no negotiation command to disable auto-negotiation on the selected interface.
Example
The following example enables flow control on port 7.
(config)#interface ethernet 1/7
(config-if)#flowcontrol
(config-if)#no negotiation
(config-if)#
Related Commands
capabilities (flowcontrol, symmetric)
Use this command to display the status for an interface.
Syntax
show interfaces status interface
- interface
- ethernet unit/port
- unit - This is device 1.
- port - Port number.
- port-channel channel-id (Range: 1-2)
- vlan vlan-id (Range: 1-4094)
Default Setting
None
Command Mode
Normal Exec, Privileged Exec
Example
#show interfaces status ethernet 1/7
Information of Eth 1/7
Basic information:
Port type: 1000t
Mac address: 00-00-e8-00-00-0a
Configuration:
Name:
Port admin status: Up
Speed-duplex: Auto
Capabilities: 10half, 10full, 100half, 100full, 1000half, 1000full,
Broadcast storm status: Enabled
Broadcast storm limit: 256 packets in queue
Flow control status: Disabled
Lacp status: Disabled
Current status:
Link status: Down
Operation speed-duplex: 100full
Flow control type: None
#
Use this command to display statistics for an interface.
Syntax
show interfaces counters interface
- interface
- ethernet unit/port
- unit - This is device 1.
- port - Port number.
- port-channel channel-id (Range: 1-2)
Default Setting
None
Command Mode
Normal Exec, Privileged Exec
Example
#show interfaces counters ethernet 1/7
Ethernet 1/7
Iftable stats:
Octets input: 19648, Octets output: 714944
Unicast input: 0, Unicast output: 0
Discard input: 0, Discard output: 0
Error input: 0, Error output: 0
Unknown protos input: 0, QLen output: 0
Extended iftable stats:
Multi-cast input: 0, Multi-cast output: 10524
Broadcast input: 136, Broadcast output: 0
Ether-like stats:
Alignment errors: 0, FCS errors: 0
Single Collision frames: 0, Multiple collision frames: 0
SQE Test errors: 0, Deferred transmissions: 0
Late collisions: 0, Excessive collisions: 0
Internal mac transmit errors: 0, Internal Mac receive errors: 0
Frame too longs: 0, Carrier sense errors: 0
RMON stats:
Drop events: 0, Octets: 734720, Packets: 10661
Broadcast pkts: 136, Multi-cast pkts: 10525
Undersize pkts: 0, Oversize pkts: 0
Fragments: 0, Jabbers: 0
CRC align errors: 0, Collisions: 0
Packet size <= 64 octets: 9877, Packet size 65 to 127 octets: 93
Packet size 128 to 255 octets: 691, Packet size 256 to 511 octets: 0
Packet size 512 to 1023 octets: 0, Packet size 1024 to 1518 octets: 0
#
Use this command to display advanced interface configuration settings.
Syntax
show interfaces switchport [interface]
- interface
- ethernet unit/port
- unit - This is device 1.
- port - Port number.
- port-channel channel-id (Range: 1-2)
Default Setting
Shows all interfaces.
Command Mode
Normal Exec, Privileged Exec
Example
This example shows the configuration setting for port 7.
#show interfaces switchport ethernet 1/7
Broadcast threshold: Enabled, 256 packets in queue
Lacp status: Disabled
VLAN membership mode: Hybrid
Ingress rule: Disabled
Acceptable frame type: All frames
Native VLAN: 1
Priority for untagged traffic: 0
Gvrp status: Enabled
Allowed Vlan: 1(u),
Forbidden Vlan:
#