A 2811 router recently was powered down and up, and on reboot, would only boot to ROMMON mode. We got this message during the boot cycle:
"Readonly ROMMON initialized
boot: cannot open "flash:"
boot: cannot determine first executable file name on device "flash:"
We read about the compact flash memory problem on some routers with certain flash modules. We have put the CF card in another 2800 series router, and the IOS image is readable there, but not on the original router.
After researching the problem on Cisco's website, we downloaded the ROMMON upgrade "C2800NM_RM2.srec.124-13r.T6", which we believed would fix this issue and also allow booting from a flash image on USB. We could then load an image into RAM from the USB and run the router, but still could not access flash. Should we have loaded the image "C2800NM_RM2.srec.124-13r.T5" first, before trying to load the "-.T6" version? Would that have fixed our compact flash problem? The CF card is still readable in other routers, so we know the flash card is okay.