So your file system has crashed… Upon running e2fsck against it you’re now seeing error such as:

Pass 1B: Rescanning for multiply-claimed blocks Multiply-claimed block(s) in inode 4195619:
167904376 167904377 167904378 167904379 167904380 167904381 167904382 167904383 167904384
167904385 167904386 167949296 167949297 167949298 167949299 167949300 167949301 167949302
167949303 167949304 167949305 167949306 

What does this all mean?

Well unfortunately for you this means that your file system has incurred major damage.

What’s happened is the inode structures around this part of the file system have been damaged to the extent that multiple inodes are claiming to own the same data blocks.

There is no way to really fix this without rolling back the file system or restoring from backup.

The inode (in the case above) which was damaged was 4195619. Some other inodes have already layed claim to the blocks listed above and now this inode is trying to also lay claim to them. Multiple inodes cannot claim the same blocks (unless of course we’re talking about special inodes such as hard links).

Sadly the inodes which were discovered before inode 4195619 could potentially be damaged and this inode could be fine. The only way to know for sure would be to dump the inode and it’s associated blocks out to a file, then verify that file based on a previous checksum you may have taken.