Cisco Catalyst 2950 Command Reference Manual page 121

Chapter 2 Catalyst 2950 and 2955 Cisco IOS Commands
When a restricted VLAN port is moved to an unauthorized state, the authentication process is restarted.
If the user fails the authentication process again, the authenticator waits in the held state. After the user
has correctly re-authenticated, all IEEE 802.1x ports are reinitialized and treated as normal IEEE 802.1x
ports.
When you reconfigure a restricted VLAN to a different VLAN, any ports in the restricted VLAN are also
moved, and the ports stay in their current authorized state.
When you shut down or remove a restricted VLAN from the VLAN database, any ports in the restricted
VLAN are immediately moved to an unauthorized state, and the authentication process is restarted. The
authenticator does not wait in a held state because the restricted VLAN configuration still exists. While
the restricted VLAN is inactive, all authentication attempts are counted. As soon as the restricted VLAN
becomes active, the port is placed in the restricted VLAN.
The restricted VLAN is supported only in single-host mode (the default port mode).
When a port is placed in a restricted VLAN, the user's MAC address is added to the MAC address table.
If a new MAC address appears on the port, it is treated as a security violation.
Examples
This example shows how to configure a restricted VLAN on Gigabit Ethernet interface 1:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# dot1x auth-fail vlan 40
Switch(config-if)# end
Switch(config)# end
Switch#
You can verify your configuration by entering the show dot1x [interface interface-id] privileged EXEC
command.
Related Commands Command
dot1x auth-fail max-attempts
[max-attempts]
show dot1x
OL-10102-01
[interface interface-id]
Description
Configures the number of authentication attempts allowed
before assigning a user to the restricted VLAN.
Displays IEEE 802.1x status for the specified port.
Catalyst 2950 and Catalyst 2955 Switch Command Reference
dot1x auth-fail vlan
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