My question is this... What does TACACS/AAA use as its default source interface?
I have a 4500 switch that is configured to authenticate through a ACS server with TACACS. The device is remote and I do not have the ability to access and enter the source interface command to specifically identify the source interface.
I know of four interfaces (all VLANS) on the device and have added each into the ACS server but the device still fails to authenticate. After reviewing the config that the local admin used, the "local" option was not added after the TACACS group so currently I have no access and the local site admin is not available to physically assist.
I initially thought it might be similar to how a ping/icmp is sourced, from the outgoing interface. I have been unable to confirm this in Cisco documentation. If it is perhaps the interface with the highest IP address this might identify my problem, as the VLAN with the highest IP (assuming there is only the 4 known VLANs) is having a routing issue.
Thanks for any help that you may be able to provide, pointing me cisco documentation would help me the most so I can perhaps learn some other ins and outs while reading. I've spent a couple hours so far searching with the nearest find stating that if you remove the source interface command it results back to the default...
Thanks,
Brandon
