Using Cisco 2800 for dial out connections

Unanswered Question
Jan 29th, 2008

We use a Cisco 2800 router with an NM-8AM-V2 (8port modem module) for users dialup applications.

A Vacman RADIUS server is used to authenticate the users.

This all works correctly, however when looking at the logs for the RADIUS server (and the RADIUS debugging on the Cisco 2800) it appears that the Cisco 2800 is requesting authentication from the RADIUS server for a user named "C" every 5 seconds.

Is this some sort of keep-alive that can be disabled on the Cisco 2800? It makes it difficult to locate useful information in the RADIUS logs when it is full of these messages.

I have attached a sample of the debug output from the Cisco 2800.

I have this problem too.
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Richard Burts Tue, 01/29/2008 - 20:29


It is pretty interesting debug output. It kind of reminds me of the situation where you have configured reverse telnet for connecting to the console port of some other device and forgot to configure no exec on the async port. Are there any async ports (especially tty 1) that are connected to a device rather than connected to a modem?

Perhaps posting the router config might give us some better clue about the problem.



steve.mccann Tue, 01/29/2008 - 21:48

Hi Rick,

There are only the 8 terminal line ports installed. Of these I believe only a couple are currently connected to phone lines. The others are vacant.

Attached is a copy of the config. It is very minimal as this device is used for dialling only.


Richard Burts Wed, 01/30/2008 - 09:31


Thanks for posting the config. It is indeed pretty minimal. I wonder about hsving this configured under lines 1 through 7:

transport input telnet

Also I wonder if you would post the output of show line



steve.mccann Mon, 02/04/2008 - 17:51

Thanks for the replies. Attached is the show line output (included detailed output for one of the lines).



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