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Rommon Update Cat 4500 with 2 Sup-Engines

What's the best way to make a rommon-update on a Cat 4500 with SSO mode ?


Re: Rommon Update Cat 4500 with 2 Sup-Engines


The easiest way to do this is use a compact flash card with the rommon file already copied to it. If you don't have one you can just copy the rommon upgrade utility to bootflash.

Since you are running SSO there "should" be little to no downtime for the users connected to the switch. I would recommend performing the upgrade after hours just in case there are any unplanned issues.

I would first fail over the active supervisor by consoling into and type

"redundancy force-switchover" which will reboot the active and let the standby take over for the switch. You will want to break the boot sequence in rommon and boot the rommon upgrade utility (from CF or bootflash) instead of the IOS. For example:

from bootflash:

boot bootflash:cat4000-ios-promupgrade-121_20r_EW1

or from CF

boot slot0:cat4000-ios-promupgrade-121_20r_EW1

This utility will run and reboot the supervisor again. This time you will want the IOS to boot and all should be well. Repeat the same process with the other supervisor.



New Member

Re: Rommon Update Cat 4500 with 2 Sup-Engines

Hi Mark,

Thanks for your reply. That's about the way we did it, but we experienced a problem:

After updating both supervisor engines one by one, the interfaces on the current standby supervisor didn't come up. Even pulling out the engine physically didn't change anything.

The only way to get back a connection was to reboot the entire switch with "redundancy reload shelf".

Has anyone experienced this issue ? We made a rommon update from 12.2(44r)SG to 12.2(44r)SG3.

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