Dell PowerConnect B-RX - 802.1 X Authentication with Dynamic VLAN Assignment

992 BigIron RX Series Configuration Guide
53-1002253-01
Sample 802.1x configurations
33
802.1X Authentication with dynamic VLAN assignment
Figure 131 illustrates 802.1X authentication with dynamic VLAN assignment. In this configuration,
two user PCs are connected to a hub, which is connected to port 2/1. Port 2/1 is configured as a
dual-mode port. Both PCs transmit untagged traffic. The profile for User 1 on the RADIUS server
specifies that User 1 PC should be dynamically assigned to VLAN 3. The RADIUS profile for User 2
on the RADIUS server specifies that User 2 PC should be dynamically assigned to VLAN 20.
FIGURE 131 Sample configuration using 802.1X authentication with dynamic VLAN assignment
In this example, the PVID for port 2/1 would be changed based on the first host to be successfully
authenticated. If User 1 is authenticated first, then the PVID for port 2/1 is changed to VLAN 3. If
User 2 is authenticated first, then the PVID for port 2/1 is changed to VLAN 20. Since a PVID
cannot be changed by RADIUS authentication after it has been dynamically assigned, if User 2 is
authenticated after the port PVID was changed to VLAN 3, then User 2 would not be able to gain
access to the network.
If there were only one device connected to the port, and authentication failed for that device, it
could be placed into the restricted VLAN, where it could gain access to the network.
The part of the running-config related to 802.1X authentication would be as follows.
dot1x-enable
re-authentication
servertimeout 10
timeout re-authperiod 10
auth-fail-action restricted-vlan
auth-fail-vlanid 1023
mac-session-aging no-aging permitted-mac-only
enable ethe 2/1 to 2/4
!
!
Hub
Untagged
Untagged
User 1
MAC: 0002.3f7f.2e0a
User 2
MAC: 0050.048e.86ac
Port 2/1
Dual Mode
BigIron Switch
RADIUS Server
Tunnel-Private-Group-ID:
User 1 -> “U:3”
User 2 -> “U:20”