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 reenable it after the problem has been resolved.
You may also want to disable a port for security reasons.
Use this command to clear statistics on an interface.
Syntax
clear countersinterface
interface
ethernetunit/port
unit - This is device 1.
port - Port number.
port-channelchannel-id (Range: 1-6)
Default Setting
None
Command Mode
Privileged Exec
Command Usage
Statistics are only initialized for a power reset. This command sets the
base value for displayed statistics to zero for the current management session.
However, if you log out and back into the management interface, the statistics
displayed will show the absolute value accumulated since the last power reset.
Example
The following example clears statistics on Ethernet port 5.
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.
When auto-negotiation is disabled, the default speed-duplex setting is 100half
for Fast Ethernet ports and 1000full for Gigabit Ethernet ports.
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
To force operation to the speed and duplex mode specified in a speed-duplex
command, use the no negotiation command to disable auto-negotiation
on the selected interface.
Example
The following example configures port 5 to 100 Mbps, half-duplex operation.
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.
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
Flow control can eliminate frame loss by “blocking” traffic from
end stations or segments connected directly to the switch when its buffers
fill. When enabled, back pressure is used for half-duplex operation and IEEE
802.3x for full-duplex operation.
When using the negotiation command to enable auto-negotiation, the
optimal settings will be determined by the capabilities command. To
enable flow control under auto-negotiation, “flowcontrol” must be
included in the capabilities list for any port
To force operation to the specified flowcontrol mode (i.e., on or
off), use the no negotiation command to disable auto-negotiation on
the selected interface.
Avoid using flow control on a port connected to a hub unless it is actually
required to solve a problem. Otherwise back pressure jamming signals may degrade
overall performance for the segment attached to the hub.
Flow control can only work on those ports located in the same chip (i.e.,
cross-chip flow control will not work).
PowerConnect 5224 - SW1: 1-12; SW2: 13-24
PowerConnect 3248 - SW1: 1-24,49; SW2: 25-48,50
Example
The following example enables flow control on port 5.
Use this command to enable and configure port security on a port. Use the no
form to disable port security or reset the intrusion action to the default.
Syntax
port security [action {shutdown | trap | trap-and-shutdown}] no port security [action]
action - Indicates the security action to be taken when a port
security violation is detected.
shutdown - Disable the port only.
trap - Issue an SNMP trap message only.
trap-and-shutdown - Issue an SNMP trap message and disable
the port.
Default Setting
Status: Disabled
Action: None
Command Mode
Interface Configuration (Ethernet)
Command Usage
If you enable port security, the switch will stop dynamically learning new
addresses on the specified port. Only incoming traffic with source addresses
already stored in the dynamic or static address table will be accepted.
To use port security, first allow the switch to dynamically learn the <source
MAC address, VLAN> pair for frames received on a port for an initial training
period, and then enable port security to stop address learning. Be sure you
enable the learning function long enough to ensure that all valid VLAN members
have been registered on the selected port.
To add new VLAN members at a later time, you can manually add secure addresses
with the mac-address-table static command, or turn off port security
to reenable the learning function long enough for new VLAN members to be registered.
Learning may then be disabled again, if desired, for security.
A secure port has the following restrictions:
It cannot be connected to a network interconnection device.
It cannot be a member of a static trunk.
It can be configured as an LACP trunk port, but the switch does not
allow the LACP trunk to be enabled.
A port that is already configured as an LACP or static trunk port cannot
be enabled as a secure port.
If a port is disabled due to a security violation, it must be manually re-enabled
by using the no shutdown command.
PowerConnect 5224 restrictions:
The switch only supports the trap-and-shutdown security action.
Although the port security action command is an Interface Configuration
command, it applies globally to all switch ports.
Example
This example sets the port security action and enables port security for
port 5.
Use this command to display status for an interface.
Syntax
show interfaces statusinterface
interface
ethernetunit/port
unit - This is device 1.
port - Port number.
port-channelchannel-id (Range: 1-6)
vlanvlan-id (Range: 1-4094)
Default Setting
None
Command Mode
Normal Exec, Privileged Exec
Command Usage
If no interface is specified, information on all interfaces is displayed.
Example
Console#show interfaces status
ethernet 1/11
Information of Eth 1/11
Basic information:
Port type: 100tx
Mac address: 00-00-e8-00-00-0a
Configuration:
Name:
Port admin: Up
Speed-duplex: Auto
Capabilities: 10half, 10full, 100half, 100full,
Broadcast storm: Enabled
Broadcast storm limit: 500 packets/second
Flow control: Disabled
Lacp: Disabled
Port security: Disabled
Port security action: None
Current status:
Link status: Down
Operation speed-duplex: 100full
Flow control type: None
Console#
