6500 720 SUP redundancy

Unanswered Question
Sep 30th, 2009

Got a 6500 with dual 720. currently the secondary sup shows a cold state. i know this means that two sups are running different IOS images.

when i check the file system the primary boots off of the sup-bootdisk:, but on the secondary there is no slavesup-bootdisk:, just slavedisk1:

question is do both of the sup's have to have the ios image located on the same storage device.

I have this problem too.
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xcz504d1114 Wed, 09/30/2009 - 07:22

No, they boot from seperate storage devices. If your primary sup fails, then your secondary would not have access to the flash of the failed sup.

I don't have a 6500 with redundant sups (mine are VSS), but my 4510R's show a slavebootflash:

Where is the current ios stored that the slave is pointed to? Is it on slavedisk1?


Giuseppe Larosa Wed, 09/30/2009 - 07:27

Hello Eddie,

there shouldn't be this requirement it should be enough for them to run the same image name and version.

this information is carried in packets exchanged in the redundancy protocol between the two supervisors.

Hope to help


TimpoSpawar724 Wed, 09/30/2009 - 07:42

sorry did not explain this correctly.

the bootvar is set to boot the ios image from the sup-bootdisk:. The secondary does not have slavesup-bootdisk:, instead the ios image is stored on the slavedisk1:

attached is the output from the show file sys command.

Mark Yeates Wed, 09/30/2009 - 09:34


Try using sup-bootflash: for your bootstrings. You will want to have your IOS stored on the same location on BOTH supervisors (such as disk0: or sup-bootflash:).




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