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New Member

Compact flash is readable in IOS but not ROMMON

I've got a handful of Cisco 2811s for study purposes and one of them came with a Kingston 256 CF that can't be read from ROMMON. I can toss it into any booted 2811 and see the contents, format it, tftp an image back on it, and read it just fine from within IOS. When trying to boot from the CF on any of those same routers it won't read the card. When it tries to read via the booting process or "dir flash:" I get the output and error below. It isn't a big deal to purchase another card but it would be good to know to stay away from certain brands, manufacture time periods, etc. The IOS and ROMMON are both up to date. Thanks in advance!




rommon 2 > dir flash:
program load complete, entry point: 0x8000f000, size: 0xc5a0

Initializing ATA monitor library.......
open(): Open Error = -66
dir: cannot open device "flash:"
rommon 3 >



Three of the routers came with Kingston flash cards and they all behave in the exact same way while the cisco cards work fine.

New Member

Issue resolved. I ended up

Issue resolved. I ended up having to partition the cards as well. Only formatting the cards in the router leaves them as FAT32 which can be read by IOS but not ROMMON. After the partition they were FAT16. I loaded up the cards and all the routers booted fine. Hopefully other folks will find this helpful.


Hall of Fame Super Gold

Ian,  Post an image of your



Post an image of your CF.   This will help people in the future.


Not all CF are supported (even if they have the same "manufacturer).

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