15.3. Restoring a bad file

Procedure 15.1. Restoring a bad file from a replicate volume

1. Note the identifiers of bad files

   Check the output of the scrub status command to determine the identifiers of corrupted files.

   # gluster volume bitrot VOLNAME scrub status
   Volume name: VOLNAME
   ...
   Node name: NODENAME
   ...
   Error count: 3
   Corrupted objects:
   5f61ade8-49fb-4c37-af84-c95041ff4bf5
   e8561c6b-f881-499b-808b-7fa2bce190f7
   eff2433f-eae9-48ba-bdef-839603c9434c

2. Determine the path of each corrupted object

   For files created after GFID-to-path translation was enabled, use the getfattr command to determine the path of the corrupted files.

   # getfattr -n glusterfs.ancestry.path -e text
   /mnt/VOLNAME/.gfid/GFID
   ...
   glusterfs.ancestry.path="/path/to/corrupted_file"

   For files created before GFID-to-path translation was enabled, use the find command to determine the path of the corrupted file and the index file that match the identifying GFID.

   # find /rhgs/brick*/.glusterfs -name GFID
   /rhgs/brick1/.glusterfs/path/to/GFID

   # find /rhgs -samefile /rhgs/brick1/.glusterfs/path/to/GFID
   /rhgs/brick1/.glusterfs/path/to/GFID
   /rhgs/brick1/path/to/corrupted_file

3. Delete the corrupted files

   Delete the corrupted files from the path output by the getfattr or find command.

4. Delete the GFID file

   Delete the GFID file from the /rhgs/brickN/.glusterfs directory.

5. Restore the file

   Follow these steps to safely restore corrupt files.

   1. Disable metadata caching

      If the metadata cache is enabled, disable it by running the following command:

      # gluster volume set VOLNAME stat-prefetch off

   2. Create a recovery mount point

      Create a mount point to use for the recovery process. For example, /mnt/recovery.

      # mkdir /mnt/recovery

   3. Mount the volume with timeouts disabled

      # mount -t glusterfs -o attribute-timeout=0,entry-timeout=0 hostname:volume-path /mnt/recovery

   4. Heal files and hard links

      Access files and hard links to heal them. For example, run the stat command on the files and hard links you need to heal.

      $ stat /mnt/recovery/corrupt-file

      If you do not have client self-heal enabled, you must manually heal the volume with the following command.

      # gluster volume heal VOLNAME

   5. Unmount and optionally remove the recovery mount point

      # umount /mnt/recovery
      # rmdir /mnt/recovery

   6. Optional: Re-enable metadata caching

      If the metadata cache was enabled previously, re-enable it by running the following command:

      # gluster volume set VOLNAME stat-prefetch on