Lost management to 3750 stack

aweise · ‎01-09-2013

Hi all,

Weird problem we just ran into. We have a 3750 stack at our DR site with 7 members in the stack - one of which is a 3750X, which also happens to be the master. Suddenly, we lost the ability to manage it via SSH, as it doesn't seem to respond to any of our ACS logins or the local user login. It's reachable and passing traffic on the network, just not manageable.

We have a Port Authority PA288 device that we have the ability to access and attempt to get to the console port. We have the console cable connected to switch #5 of the stack (we've tried others, as well) and are able to connect to the console. However, we continually get the text:

====================

SwitchStack-5 con0 is now available

Press RETURN to get started.

====================

Every time we hit the return/enter key, the screen refreshes to this - as if the device was finished rebooting and ready for you to login. Unfortunately, we NEVER get the Username prompt. As I said, we tried the console on two other switches in the stack, but ended up with the same result. None of these switches are the master, however (would that make a difference?).

I've never seen this on a 3750 stack....any ideas?

For what it's worth, we also saw the following log message about 5 times when we first connected the console cable:

"Can not remove non-existent route-map"

Thanks!

Gregory Snipes · ‎01-09-2013

7 is a pretty large stack of 3750s. I have seen the control plane have issues in larger stacks on occasion. Mixing different models together (as you are doing) has seemed to increase the chances of this happening as well.

You should be using the console port of the master if you are attempting to manage the stack via console. I have yet to see any documentation that sates this is required but have often run into problems trying to console into non-master switches.

glen.grant · ‎01-09-2013

I almost think that is normal in non stackmaster switches. Did you try all switches in the stack and you couldn't get into any ? If so then you may end up booting the entire stack. What output did you get on the stackmaster?