Strange behavior in 3750 stack.

psiegling · ‎10-19-2012

We have a stack with three 3750 48 Port 10/100 PoE switches and on 3750G 24 port PoE switch. The 1Gb uplink for the stack is on the 1st 48 port (member 2) of the stack. Running the 12.2 (55) K-9 code.
The master in the stack (Member 3) appeared to be not able to communicate with the DHCP and all users attached to this switch were getting 169.0.0.0 addresses. A reboot of the switch seemed to fix the problem, until this morning when the 48 port member 4 displayed the same condition.

The active port lights were all blinking green simultaneously, not like traffic was passing. When the second switch was rebooted, the problem went back to member 3.

Anyone seen this before. New one for me. Does not feel like hardware, but could be a stack cable gone bad. Feels more a code corruption problem.

Ideas. Thank you....

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Leo Laohoo · ‎10-22-2012

Running the 12.2 (55) K-9 code.

Exactly what IOS version? It should be 12.2(55)SEn where "n" is either a blank or a number.

Can you post the configuration example of the port?

Is the switch stack acting as a DHCP server or is there a DHCP server? If there is a DHCP server, is this server connected to the same switch stack?