Unable to telnet to router

[Alistair-Roberts]

Hi,

Our main router is a 3640. Up until today it's been working fine, but today I can't telnet into it. I've also tried to console to it but get no login.

The router is still running, apart from powering off and on, not sure what else to do.

Any ideas?

[ywadhavk]

Hi,

Is this router setup for authentication to a AAA server? When you telnet into it, what is the response? Do you get the username/password prompt at all?

By mentioning "router is still running" , did you mean by the router is still passing traffic?

Was there a config ( e.g. turning on aaa new-model) carried out?

Thanks,

yatin

[Alistair-Roberts]

I get no prompt when I try and telnet, get a connect failed. I've tried getting in various ways. E.g. telnet to one of the WAN routers then try and telnet back to the main router.

We have a radius server, this is running fine.

The router is still passing traffic OK, just worried it's on the verge of crashing.

[ywadhavk]

If this is the same with the Console, then most likely the router is overwhelmed, maybe due to debugs left running on it or traffic is over capacity.

If you were to yank a connection (outside) for e.g. and try to telnet / console back in, and if it allows you to do so, then its probably due to overcapacity traffic (DoS??) OR if you don't want the excersize to be intrusive, have a sniffer on the outside and then on the inside connections and see if the traffic is unduly high or inappropriate.

Reboot would be the last resort. But at least doing the above would give us a clue as to whats going on.

Thanks,

yatin

[Alistair-Roberts]

Traffic across the links aren't saturated as the MRTG graphs are still working.

Thanks