Can't login because of Cisco ACS or ACS remote agent

[chicagotech]

Case 1: The client uses Cisco ACS to control the network access. Since the ACS has a hardware issue and it doesn't function, no users can logon the network.

Case 2: The client setup Cisco ACS with a remote agent to control the network access. After the remote agent crashes, no users can't logon.

Resolution: use "no aaa authentication login default group radius local" to disable the radius and then "aaa authentication login default group local" enable local authentication.