Quote:
Originally Posted by
maraixadm
So again, I don't want to modify it live
But you
are modifying it live. It's like trying to read a dictionary while someone else is constantly changing the order of the words -- possibly tearing out pages while they're at it, if they're writing to a corrupt filesystem. If you at least made it read-only, stopped moving things around, it'd be possible to check it.
The kernel makes an awful lot of assumptions about the state of the filesystem. It's the job of it and the journal to keep it that way, but if something else unintentionally alters the filesystem tree -- power outage, disk failure, controller glitch, whatever -- these assumptions may be violated, and using it can cause bad things to happen. Like an index pointing to the wrong disk cluster, causing data to be overwritten or two files to unintentionally share contents, or a file just not mentioned at all anywhere and disappearing from disk, etc, etc.
fsck makes as few assumptions as possible, but
does assume the filesystem isn't changing. That's the tradeoff it makes.