Backup Boot Image on SUP720

Unanswered Question
Sep 25th, 2008

I am not able to get a SUP720 to boot the second image specified, if the CF card is removed.

I have just finished converting a SUP720-BASE from Hybrid mode to Native IOS mode. I had a small issue during this procedure, where I didn't format the CF before I put the native IOS image on it, but I stopped, formatted it, recopied IOS and went on, that seems fixed.

I then formatted sup-bootflash: and bootflash: (each 64M) and copied the "backup" IOS image on them. I then use:


boot system flash disk0:s72033-ipservicesk9_wan-mz.122-33.SXH2a.bin

boot system flash sup-bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin

boot system flash bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin


to specify a 'backup' image. This is confirmed by sh bootvar:

Router#sh bootvar

BOOT variable = disk0:s72033-ipservicesk9_wan-mz.122-33.SXH2a.bin,1;sup-bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin,1;bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin,1;

CONFIG_FILE variable =

BOOTLDR variable =

Configuration register is 0x2102

Standby is not present.

Router#remote command switch sh bootvar

BOOT variable = disk0:s72033-ipservicesk9_wan-mz.122-33.SXH2a.bin,1;bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin,1;bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin,1;

CONFIG_FILE variable =

BOOTLDR variable =

Configuration register is 0x2102


But when I remove the CF card and reload the switch, it fails to find the disk0: image, and drops into ROMMON. I am then able to manually boot from the bootflash: image.

But I am expecting that the switch should go the second image specified, if the first image is unavailable. My partner says at least one other SUP720 (a 3B) exhibits the same behavior, but we both think the second imagte specified should be booted automatically.

We can't find any reference to a conf-reg setting ort anything that would turn this on or off. Anyone have knowledge of how this is supposed to work? TIA


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Overall Rating: 4 (2 ratings)
Mark Yeates Thu, 09/25/2008 - 10:26


Try using bootdisk: instead of bootflash: in your boot strings. Most newer IOS images use the bootdisk string.



PAUL TRIVINO Thu, 09/25/2008 - 10:44

Thanx Mark. I should mention that the SUP doesn't even TRY to find the next file specified - it finds disk0: isn't there and drops to ROMMON:

System Bootstrap, Version 7.7(1)

Copyright (c) 1994-2003 by cisco Systems, Inc.

Cat6k-Sup720/SP processor with 524288 Kbytes of main memory

Autoboot executing command: "boot disk0:s72033-ipservicesk9_wan-mz.122-33.SXH2a.bin"

PCMCIA slot0 device is not initialized

open: read error...requested 0x4 bytes, got 0x0

trouble reading device magic number

loadprog: error - on file open

boot: cannot load "disk0:s72033-ipservicesk9_wan-mz.122-33.SXH2a.bin"

System Bootstrap, Version 7.7(1)

Copyright (c) 1994-2003 by cisco Systems, Inc.

Cat6k-Sup720/SP processor with 524288 Kbytes of main memory

rommon 1 >

ALSO: When I manually boot from ROMMON using

rommon 1 > boot bootflash:s72033-pk9sv-mz.122-17d.SXB8.bin

Self decompressing the image : ##########################...etc.

it boots OK, I just want it to happen automatically. Thanx!

Mark Yeates Thu, 09/25/2008 - 10:47

That is strange. I would try a rommon upgrade on the SP side since yours is pretty old. It should default to the second image as specified in your boot strings.

PAUL TRIVINO Thu, 09/25/2008 - 10:55

Another good call, Mark. A quick check shows this is the oldest ROMMON of my collection of SUP720's but I think it's also the only SUP720-BASE (PFC3A). Thanks again.


Mark Yeates Thu, 09/25/2008 - 11:33

You can use the same rommon the 720 base as you can the sup720-3b. The SP is the one that should be upgraded. The latest is 8-5-3.


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