[c-nsp] Invalid checksum on 2621 flash

[Vincent De Keyzer]

Hello list,
 
yesterday evening I was rebooting a 2621 remotely (with the help of the
terminal server) and it didn't go very smoothly.
 
The console was showing messages about failing to load the image
(unfortunately I didn't capture the output), but it eventually booted with
the version it claimed it couldn't load (!?!...).
 
After that, I did a "show flash:" and I saw the flash empty (this also is
weird)! So I tried to download an image from a fellow 2621 sitting next to
the first one, but the checksum appeared to be invalid. I retried twice and
every time the checksum was invalid (although different).
 
One option is of course to replace the router, but I wonder whether this
wrong checksum actually is a problem. Maybe everything is OK despite these
"invalid checksums" and "failed to load" messages?... Maybe the router is
just bad at arithmetics? :-)
 
Could anyone with a better understanding (than mine) of flash and checksums
shed some light on this?
 
Vincent