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New Member

Setting boot var in 6500 switches

Hi all,

I usally have problem in setting boot variable in chasis based switches(single or redundant sup) or 7600 routers.

confused with sup-bootdisk, bootdisk, sup-bootflash, disk0, system flash, boot flash... etc.

What decides to set up correct boot variables?

Thanks & Regards


Cisco Employee

Re: Setting boot var in 6500 switches

I think you need to understand what are these file systems first.

In the 6500/7600, the supervisor card has two main components, Switch Processor (SP), aka SUP, and Route Precessor (RP), aka MSFC.

On most of the current IOS, the image should be stored in the SP since this will come up first (RP is a daughter card on the SP).

sup-bootflash, sup-bootdisk are the SP's flash space. However, it depends on which version of IOS, some IOS only accept the string of sup-bootflash/sup-bootdisk.

bootflash is the flash space on the RP, it is not necessary to copy the IOS into this space, since the RP will download it off SP while it is booting up. Most likely, this space has only 64MB.

disk0, disk1 are the external flash memory (CF cards).

You can use the command show file system to help look up the disk size and the naming convention. Most of the time, I use boot system flash sup-boot.....



New Member

Re: Setting boot var in 6500 switches

Jerry, thanks for the useful info.  Along these lines, I purchased a 512MB upgrade DIMM for the SP socket, which did not take (running 12.2(17d)SXB11a).

If I remove the CF and mount it in the disko: slot, it works fine. Should I just continue to use the 512MB in disk0: and set the BootVars accordingly?



Cisco Employee

Re: Setting boot var in 6500 switches

Using disk0: instead of sup-bootflash: is absolute fine. Just make sure no one is going to "borrow" the CF for a day while something happen to the switch.