dumpe2fs
 

Okay, I'm studying for my LPIC-1 and looking at the dumpe2fs command, I keep getting complaints about a bad magic number. What does that mean?

Specifically, this:
linux-1u45:/home/jmeyer # dumpe2fs /dev/sda2
dumpe2fs 1.39 (29-May-2006)
dumpe2fs: Bad magic number in super-block while trying to open /dev/sda2
Couldn't find valid filesystem superblock.

I'd say that means the partition is not ext2 (or 3) or that it is corrupted.

I think the "magic number" is like a tag that helps programs find certain data structures (eg the last two bytes of the mbr)

Which is real strange, since the computers working well.