DELL 9.7(0.0) User Manual

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If the supplicant fails authentication, the authenticator typically does not enable the port. In some cases 
this behavior is not appropriate. External users of an enterprise network, for example, might not be able 
to be authenticated, but still need access to the network. Also, some dumb-terminals, such as network 
printers, do not have 802.1X capability and therefore cannot authenticate themselves. To be able to 
connect such devices, they must be allowed access the network without compromising network security.
The Guest VLAN 802.1X extension addresses this limitation with regard to non-802.1X capable devices 
and the Authentication-fail VLAN 802.1X extension addresses this limitation with regard to external users.
• If the supplicant fails authentication a specified number of times, the authenticator places the port in 
the Authentication-fail VLAN.
• If a port is already forwarding on the Guest VLAN when 802.1X is enabled, the port is moved out of 
the Guest VLAN and the authentication process begins.
Configuring a Guest VLAN
If the supplicant does not respond within a determined amount of time ([reauth-max + 1] * tx-period, the 
system assumes that the host does not have 802.1X capability and the port is placed in the Guest VLAN.
NOTE: For more information about configuring timeouts, refer to 
.
Configure a port to be placed in the Guest VLAN after failing to respond within the timeout period using 
the dot1x guest-vlan command from INTERFACE mode. View your configuration using the show 
config command from INTERFACE mode or using the show dot1x interface command from EXEC 
Privilege mode.
Example of Viewing Guest VLAN Configuration
Dell(conf-if-Te-2/1)#dot1x guest-vlan 200
Dell(conf-if-Te 2/1))#show config
!
interface TenGigabitEthernet 21
  switchport
  dot1x guest-vlan 200
  no shutdown
Dell(conf-if-Te 2/1))#
Configuring an Authentication-Fail VLAN
If the supplicant fails authentication, the authenticator re-attempts to authenticate after a specified 
amount of time.
NOTE: For more information about authenticator re-attempts, refer to 
You can configure the maximum number of times the authenticator re-attempts authentication after a 
failure (3 by default), after which the port is placed in the Authentication-fail VLAN.
Configure a port to be placed in the VLAN after failing the authentication process as specified number of 
times using the dot1x auth-fail-vlan command from INTERFACE mode. Configure the maximum 
number of authentication attempts by the authenticator using the keyword max-attempts with this 
command.
Example of Configuring Maximum Authentication Attempts
Dell(conf-if-Te-2/1)#dot1x guest-vlan 200
Dell(conf-if-Te 2/1)#show config
90
802.1X