cache_check - Man Page
validates cache metadata on a device or file.
Synopsis
cache_check [options] {device|file}
Description
cache_check checks cache metadata created by the device-mapper cache target on a device or file.
This tool cannot be run on live metadata.
Options
- -h, --help
Print help and exit.
- -V, --version
Output version information and exit.
- -q, --quiet
Suppress output messages, return only exit code.
- --super-block-only
Only check the superblock.
- --skip-hints
Skip checking of the policy hint values metadata.
- --skip-discards
Skip checking of the discard bits in the metadata.
- --clear-needs-check-flag
Clears the 'needs_check' flag in the superblock.
The kernel may set a flag to force the pool to be checked before it's next activated. Set this switch to clear the flag if the check is successful. If the metadata check failed, the flag is not cleared and a cache_repair run is needed to fix any issues. After cache_repair succeeded, you may run cache_check again.
Example
Analyses and repairs cache metadata on logical volume /dev/vg/metadata:
$ cache_check /dev/vg/metadata
The device may not be actively used by the target when running.
Diagnostics
cache_check returns an exit code of 0 for success or 1 for error.
See Also
Author
Joe Thornber <ejt@redhat.com>, Heinz Mauelshagen <HeinzM@RedHat.com>
Referenced By
cache_dump(8), cache_repair(8), cache_restore(8), cache_writeback(8), lvmcache(7).