TACACS shows "Unknown NAS" from configured device

Unanswered Question
Dec 24th, 2007
User Badges:

I have a router that has been configured in TACACS and suddenly started to fail login attempts.

TACACS is configured to source from the Loopback Internface on the router and I can ping it from the TACACS server.

I can log in with localy configured credentials on the router and the TACACS config is intact, I also have a switch at the same site and it is authenticating to TACACS with no problems.

When looking in TACACS, I see "Unknown NAS" with the source being the Serial Interface of the router.

Anyone ever see anything like this?

Would a router reboot be in order or possible a corrupted TACACS database?

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
yjdabear Mon, 12/24/2007 - 09:09
User Badges:
  • Gold, 750 points or more


"Authentication fails; the error "Unknown NAS" appears in the Failed Attempts log.

Verify the following:

•AAA client is configured under the Network Configuration section.

•If you have RADIUS/TACACS source-interface command configured on the AAA client, make sure the client on ACS is configured using the IP address of the interface specified.

Alternatively, you can configure a default NAS in the NAS configuration area by leaving the hostname and IP address blank and entering only the key."

wilson_1234_2 Tue, 12/25/2007 - 05:53
User Badges:

I appreciate your reply, but you are just confirming what I put in my post.

All of that has been verified.

This has been working and suddenly does not.

No config has changed, reloading the router corrected the issue.


This Discussion