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New Member

Router Locking UP

I have two routers connected together and one of them occasionally (every two weeks or so) locks up.

By 'locks up' I mean, I cannot ping the interface from anywhere but if I am on the connected router I can telnet to Once on the router no traffic will leave the router, out any interface. All interfaces are up up, and I don't see any errors counted. The only way to solve the issue is to reset router

There is also another router connected to which is and it is setup exactly the same as and is the same router same IOS and it does not have this issue.


Any ideas?


Re: Router Locking UP

Looks like a troubleshooting scenario.

1. Enable logging (if not enabled already - use "logging buffered 128000 debugging" for example)

2. Check the log. It has to say something if something happened.

3. Check routing relations if you are running interior gateway protocol.

It could be anything. Bad backplane, failing controller, errors on the interface and so on.

We had a problem with 3750s with 12.1(19)EAB IOS. It had a bug - when you connected 10Mbps device to it's 10/100/1000 ports after a while the Ethernet controller would fail and would not be able to send anything out of any interface.

New Member

Re: Router Locking UP

I will certainly enable the logging.

No routing enabled, we only have a default route to

I suspected a hardware issue, so I had Cisco send out a new router.....and then two weeks (or so) later the same thing happens.

Very frustrating!

I also tried bouncing the interfaces on both router (I have console access to it when this happens) and that does not fix it.