Cisco catalyst 3750 Command Reference Manual page 211

Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
Command Default Detection is enabled for all causes. All causes, except for per-VLAN error disabling, are configured to
shut down the entire port.
Command Modes Global configuration
Command History Release
12.1(11)AX
12.1(14)EA1
12.1(19)EA1
12.2(20)SE
12.2(25)SE
12.2(37)SE
12.2(46)SE
Usage Guidelines A cause (link-flap, dhcp-rate-limit, and so forth) is the reason why the error-disabled state occurred.
When a cause is detected on a port, the port is placed in an error-disabled state, an operational state that
is similar to a link-down state.
When a port is error-disabled, it is effectively shut down, and no traffic is sent or received on the port. For
the BPDU, voice aware 802.1x security, guard and port-security features, you can configure the switch
to shut down just the offending VLAN on the port when a violation occurs, instead of shutting down the
entire port.
If you set a recovery mechanism for the cause by entering the errdisable recovery global configuration
command for the cause, the port is brought out of the error-disabled state and allowed to retry the
operation when all causes have timed out. If you do not set a recovery mechanism, you must enter the
shutdown and then the no shutdown commands to manually change the port from the error-disabled
state.
Examples
This example shows how to enable error-disable detection for the link-flap error-disabled cause:
Switch(config)# errdisable detect cause link-flap
This command shows how to globally configure BPDU guard for per-VLAN error disable:
Switch(config)# errdisable detect cause bpduguard shutdown vlan
This command shows how to globally configure voice aware 802.1x security for per-VLAN error
disable:
Switch(config)# errdisable detect cause security-violation shutdown vlan
You can verify your settings by entering the show errdisable detect privileged EXEC command.
OL-8552-07
Modification
This command was introduced.
The loopback keyword was added.
The dhcp-rate-limit keyword was added.
The arp-inspection keyword was added.
The l2ptguard keyword was added.
The Per-VLAN error-detection feature was added. The inline-power and
sfp-config-mismatch keywords were added.
The security-violation shutdown vlan keywords were added.
errdisable detect cause
Catalyst 3750 Switch Command Reference
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