Why the Cisco 2960S Randomly Reboots

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Why the Cisco 2960S Randomly Reboots

Post by grady »

Having a strange problem, my Cisco 2960S keep randomly restarting. They are stacked and are running IOS version 12.2(58) SE2. I also can't find a crash log file in the flash directory after they randomly reboot.

Ive checked the show version with no avail, but it does indicate a possible power issue:
System returned to ROM by power-on
System restarted at 09:11:13 PAC Tue Nov 15 2011
System image file is "flash:/c2960s-universalk9-mz.122-58.SE2/c2960s-universalk9-mz.122-58.SE2.bin"

Im not too sure, but the switch is connected to a ups, that a few other switches are also connected to and they did not go offline during the time the switch did.
I am not sure whats going on, as I have nothing to base it on.
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Re: Why the Cisco 2960S Randomly Reboots

Post by nicolas_cyprus »

Did you check each stack member's flash one by one?

For example to view the flash contents of stack member 3 you type:

Switch# dir flash3:

And to 'see' stack 3 you type session 3
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Re: Why the Cisco 2960S Randomly Reboots

Post by dellpe »

The line "System returned to ROM by power-on" usually means that the switch thinks it reset due to power loss. So you may have a power issue, or possibly the power supply in the switch is bad. Can you swap the stack master roles so the other switch is master? It's unlikely that both switches have bad power supplies, so with the other switch running the stack, you should be able to look at the logs and see if the first switch looses power alone, or if both switches go down and come back up at the same time.

You may also try moving your 2960s to a different port of the UPS

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