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C 3750 Switch Stack Problems - Adding additional switches

Unanswered Question

I have a stack of four 3750s and am trying to add in an additional one - we've connected the switch into the stackwise 'loop' but when the switch boots up, it seems to get stuck during POST - stopping with the Sys and RPS LEDs lit.

There is no response from the switch when connecting a console cable nor is the switch visible in CNA or Cview when connected to the stack.

Has anyone seen this before?


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amit-singh Tue, 10/18/2005 - 23:48
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What happens if you take the switch out of the stack and then console into it...

Do you have the same hardware on all the 4 and the new switch.

Please revert


-amit singh

The existing switches are 2x 3750G-12S and 2x 3750G-24T .. The new addition is another 3750G-24T.

We preconfigured the IP address/gateway/host settings on the new switch using the Express Setup method before installing it in the stack, so we know the switch itself works on its own.

We've tried booting the switch up monitoring the console.. it appears to boot as normal, then the Switch Master election takes place and it says switch 4 elected master, switch 1 has become slave, it then displays some more information, but no error messages, and then freezes.

I will get a dump of the console output ASAP..

Thanks for your help.

amit-singh Wed, 10/19/2005 - 01:27
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Please try to see the logs on the switches and see if it generates any error messgae.

Try to capture the output of " show platform stack-manager all ".


-amit singh

Thanks for your help Amit;

I disconnected the power from the new switch, connected a console cable up to the existing stack switch and the reconnected the power for the new switch - It turns out the new switch has an incompatible IOS version, so I will have to update the software on the existing switches.

Again - thanks for your help.



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