DELL N3000 User Manual

Configuring Port and System Security

Authentication priority allows a higher-priority method (not currently 

running) to interrupt an authentication in progress with a lower-priority 

method. Alternatively, if the client is already authenticated, an interrupt from 

a higher-priority method can cause a client, which was previously 

authenticated using a lower-priority method, to reauthenticate. 
For example, if a client is already authenticated using a method other than 

802.1X (MAB or captive portal) and 802.1X has higher priority than the 

authenticated method, and if an 802.1X frame is received, then the existing 

authenticated client is removed and the authentication process begins again 

from the first method in the order. If 802.1X has a lower priority than the 

authenticated method, then the client is not removed and the 802.1X frames 

are ignored.
If administrator changes the priority of the methods, then all the users who 

are authenticated using a lower-priority method are forced to reauthenticate. 

If an authentication session is in progress and the administrator changes the 

order of the authentication methods, then the configuration will take effect 

for the next session onwards.

In this scenario, the authentication manager selects the first authentication 

method, 802.1X. If authentication using 802.1X is successful, then the client 

is allowed network access. If authentication using 802.1X errors out, then 

authentication manager selects the next authentication method: MAB. If 

authentication using MAB returns an error, then the port is unauthorized. 

The authentication manager will start a timer to re-authenticate the client. 

At the expiry of the timer, the authentication manager restarts authentication 

by selecting the 802.1X method.

console#configure

console(config)#radius-server host 10.10.10.10

console(Config-radius)#name BigRadius

console(Config-radius)#primary

console(Config-radius)#usage 802.1x

console(Config-radius)#exit

console(config)#radius-server key thatsyoursecret-keepit-keepit

console(config)#authentication enable

console(config)#aaa authentication dot1x default radius

console(config)#dot1x system-auth-control

console(config)#interface te1/0/4

console(config-if-Te1/0/4)#authentication order dot1x mab