Permission Rescue: getfacl to Save Your Future Self

Luke Hebert

- 2 minutes read - 297 words

Losing file permissions after a migration, a failed restore, or a misapplied chmod can lock you out of critical data in a hurry. The good news is that Linux gives you a clean, two-command workflow to snapshot and restore the full permission set of any directory tree.

Backing Up Permissions

Use getfacl in recursive mode to capture every file and folder’s ACL, ownership, and mode into a single text file:

getfacl -R /path/to/directory > perms.to.restore

The -R flag walks the entire subtree. The output is a plain-text file that includes owner, group, mode, and any extended ACL entries for each path.

Restoring Permissions

When you are ready to put everything back, feed that file to setfacl:

setfacl --restore=perms.to.restore

A few things to keep in mind:

  • --restore expects the exact format produced by getfacl -R (or a compatible tool).
  • If the backup contains owner or group comments and you run setfacl as root, the owner and owning group of every file are restored as well.
  • This option cannot be combined with other setfacl options, with the single exception of --test.

Dry Run with --test

Before committing a large restore, preview what would change:

setfacl --restore=perms.to.restore --test

--test prints the actions it would take without actually modifying the filesystem, so you can verify the scope before the real run.

Quick Tips

  • Store the backup file somewhere outside the directory tree you are backing up, so a restore of that tree does not overwrite the backup itself.
  • If you only need to restore a subset, you can filter the text file with grep or awk before passing it to setfacl --restore.
  • Permissions restored this way include extended ACLs, not just the standard rwx bits, which makes this approach more complete than a simple chmod or chown pass.