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2960 running IOS ver 12.2(25r)FX Freezes up??

I have encountered a really strange problem on a new batch of switches I recently received. Everytime I try to copy and paste a config into a telnet session, the switch "freezes" up and I lose access to it, and it falls off the network. Eventually, about 3-5 minutes later, it comes back. Nothing in the log, although I'm not debugging anything in particular either. Anyone have any ideas?




Re: 2960 running IOS ver 12.2(25r)FX Freezes up??

Well, you have to consider that you are pasting a configuration to a switch via telnet. The symptom you described could be a number of thing and it depends where the apparent "hang" happens. It could be spanning tree in which the STP goes through it's calcualation which takes about 45 secs. or it could be routing table reconverging where you lose your telnet and then regain once the RP is converged. There is no way to tell and you are fortunate you are not pasting a config with an encrytped password and you don't know what the password is and have to do a pasword recovery. however, if you really wnat to finds out, instead of pasting the entire config do it line by line to see which config causes the apparent hang or lost connection.

Community Member

Re: 2960 running IOS ver 12.2(25r)FX Freezes up??

Thanks, actually it's not a particular command that's causing the problem, it's actually the act of the paste itself.. I initially tried MS telnet and that failed consistently. Pasting in small bits seemed to be ok, but posting an entire config caused a problem. Using Hyperterminal it seemed to work fine. Pretty bizzare that pasting some stuff into the MS telnet client could cause the switch to hang.

Community Member

Re: 2960 running IOS ver 12.2(25r)FX Freezes up??

It is ms telnet program and the network interface.

I have an hp laptop and it does the same via telnet.

If I use SSH, I don't have this issue.

The hang is your network interface dropping.

I would make a bet that the actual switch is still running just fine.

Community Member

Re: 2960 running IOS ver 12.2(25r)FX Freezes up??


I met the exact same issue on 2960 running the same version. I was connected with console line to the switch while someone pasted the configuration via telnet. On the switch everything was working fine but I couln't ping anymore my gateway. Wouldn't it be a buffer/bug issue on the 2960 ?

When you talk about network interface, tou dela with the PC network card ?

Best regards,

Romain PAGE

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