btrfs-scrub(8) ============== NAME ---- btrfs-scrub - scrub btrfs filesystem SYNOPSIS -------- *btrfs scrub* DESCRIPTION ----------- *btrfs scrub* is used to scrub a btrfs filesystem, which will reading all data from all disks and verifying checksums. SUBCOMMAND ---------- *start* [-BdqrRf] [-c -n ] |:: Start a scrub on all devices of the filesystem identified by or on a single . If a scrub is already running, the new one fails. + Without options, scrub is started as a background process. Progress can be obtained with the *scrub status* command. Scrubbing involves reading all data from all disks and verifying checksums. Errors are corrected along the way if possible. + The default IO priority of scrub is the idle class. The priority can be configured similar to the `ionice`(1) syntax using '-c' and '-n' options. + `Options` + -B:::: Do not background and print scrub statistics when finished. -d:::: Print separate statistics for each device of the filesystem (-B only). -q:::: Quiet. Omit error messages and statistics. -r:::: Read only mode. Do not attempt to correct anything. -R:::: Raw print mode. Print full data instead of summary. -c :::: Set IO priority class (see ionice (1) manpage). -n :::: Set IO priority classdata (see `ionice`(1) manpage). -f:::: Force starting new scrub even if a scrub is already running. This is useful when scrub stat record file is damaged. *cancel* |:: If a scrub is running on the filesystem identified by , cancel it. + Progress is saved in the scrub progress file and scrubbing can be resumed later using the scrub resume command. If a is given, the corresponding filesystem is found and scrub cancel behaves as if it was called on that filesystem. *resume* [-BdqrR] [-c -n ] |:: Resume a canceled or interrupted scrub cycle on the filesystem identified by or on a given . + Does not start a new scrub if the last scrub finished successfully. + `Options` + see *scrub start*. *status* [-d] |:: Show status of a running scrub for the filesystem identified by or for the specified . + If no scrub is running, show statistics of the last finished or canceled scrub for that filesystem or device. + `Options` + -d:::: Print separate statistics for each device of the filesystem. EXIT STATUS ----------- *btrfs scrub* returns a zero exit status if it succeeds. Non zero is returned in case of failure. AVAILABILITY ------------ *btrfs* is part of btrfs-progs. Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for further details. SEE ALSO -------- `mkfs.btrfs`(8),