thin_check man page

thin_check — validate thin provisioning metadata on device or file


thin_check [options] {device|file}


thin_check checks thin provisioning metadata created by the device-mapper thin provisioning target on a device or file.

This tool cannot be run on live metadata.


-q, --quiet

Suppress output messages, return only exit code.

-h, --help

Print help and exit.

-V, --version

Output version information and exit.


Clear the needs-check-flag in case the check of the thin pool metadata succeeded. If the metadata check failed, the flag is not cleared and a thin_repair run is needed to fix any issues. After thin_repair succeeded, you may run thin_check again.


Only check the superblock is present.


Skip checking of the block mappings which make up the bulk of the metadata.


thin_check will only return a non-zero exit code if it finds a fatal error.  An example of a non fatal error is an incorrect data block reference count causing a block to be considered allocated when it in fact isn't.  Ignoring errors for a long time is not advised, you really should be using thin_repair to fix them.


Analyses thin provisioning metadata on logical volume /dev/vg/metadata:

thin_check /dev/vg/metadata

The device must not be actively used by the target when running.


thin_check returns an exit code of 0 for success or 1 for error.

See Also

thin_dump(8) thin_repair(8) thin_restore(8) thin_rmap(8) thin_metadata_size(8)


Joe Thornber <>
Heinz Mauelshagen <>

Referenced By

thin_dump(8), thin_metadata_size(8), thin_repair(8), thin_restore(8), thin_rmap(8).

Thin Provisioning Tools Red Hat, Inc.