1 of the 2 core switches gone bad - cant' find out why

Unanswered Question
Apr 15th, 2008

The network was working good with 2 3560G switches working as core

switch.We had a power failure and since then the network is only

stable if 1 core switch is running. if we turn on the 2nd everything

goes down after 5 minutes. it might come back after some 5 minutes

and goes down again. If i switch of the 2nd core switch all goes

back to normal. configuration seems normal. we have not changed

anything. I wonder if the 2nd core switch has hardware damage.

any one as any clues?


I have this problem too.
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Hi, if the switch run for about five minutes and then it turns off could be overheating. If you have SNMP logging setup check the snmp temperture logs and see, also could be a bug in the system. Since you said this issue started after a power outage i would look at the switch power supply. next time you turn on the switch run a show log command and look for problems. Also run the show enviroment command and check the temperture on the switch, ex:output below.


nhb-eg28-sw1#show environment

no alarm

Chassis Temperature = 35 degrees Celsius

Chassis Over Temperature Threshold = 75 degrees Celsius

Chassis Critical Temperature Threshold = 95 degrees Celsius

Power Fan Inline

Supply Model No Type Status Sensor Status

------ ---------------- --------- ----------- ------- -------

PS1 PWR-C45-2800AC AC 2800W good good good

PS2 PWR-C45-2800AC AC 2800W good good good

Power supplies needed by system : 1

Power supplies currently available : 2

Chassis Type : WS-C4506

Power consumed by backplane : 0 Watts

Supervisor Led Color : Green

Module 1 Status Led Color : Green

edniagara Wed, 04/16/2008 - 14:58

thanks for the tip.

i tried that but no luck.

i even replaced the switch with another one and the same problem appears.

i disconnected all the cables from the core switch 2 and connected it to the network. started to add cable by cable (that connect to other access switches) and it seems to work. on one of the cables that connect to other switches in the network, after connecting it the network started to come down. i shut down the phones vlan and all came back again....i wonder if its spanning tree failure..... still exploring other options.


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