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New Member

TACACS shows "Unknown NAS" from configured device

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?


Re: TACACS shows "Unknown NAS" from configured device

"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."

New Member

Re: TACACS shows "Unknown NAS" from configured device

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.