quotacheck - scan a filesystem for disk usage, create, check and repair quota files
quotacheck [ -gubcfinvdMmR ] [ -F quota-format ] -a | filesystem
quotacheck examines each filesystem, builds a table of current disk usage, and compares
this table against that recorded in the disk quota file for the filesystem (this step is
ommitted if option -c is specified). If any inconsistencies are detected, both the quota
file and the current system copy of the incorrect quotas are updated (the latter only
occurs if an active filesystem is checked which is not advised). By default, only user
quotas are checked. quotacheck expects each filesystem to be checked to have quota files
named [a]quota.user and [a]quota.group located at the root of the associated filesystem.
If a file is not present, quotacheck will create it.
If the quota file is corrupted, quotacheck tries to save as much data as possible. Rescu-
ing data may need user intervention. With no additional options quotacheck will simply
exit in such a situation. When in interactive mode (option -i) , the user is asked for
advice. Advice can also be provided from command line (see option -n) , which is useful
when quotacheck is run automatically (ie. from script) and failure is unacceptable.
quotacheck should be run each time the system boots and mounts non-valid filesystems.
This is most likely to happen after a system crash.
It is strongly recommended to run quotacheck with quotas turned off on for the filesystem.
Otherwise, possible damage or loss to data in the quota files can result. It is also
unwise to run quotacheck on a live filesystem as actual usage may change during the scan.
To prevent this, quotacheck tries to remount the filesystem read-only before starting the
scan. After the scan is done it remounts the filesystem read-write. You can disable this
with option -m. You can also make quotacheck ignore the failure to remount the filesystem
read-only with option -M.
-b Forces quotacheck to make backups of the quota file before writing the new data.
-v quotacheck reports its operation as it progresses. Normally it operates silently.
-d Enable debugging mode. It will result in a lot of information which can be used in
debugging the program. The output is very verbose and the scan will be slow.
-u Only user quotas listed in /etc/mtab or on the filesystems specified are to be
checked. This is the default action.
-g Only group quotas listed in /etc/mtab or on the filesystems specified are to be
-c Don't read existing quota files. Just perform a new scan and save it to disk. quo-
tacheck also skips scanning of old quota files when they are not found.
-f Forces checking of filesystems with quotas enabled. This is not recommended as the
created quota files may be out of sync.
-M This flag forces checking of filesystem in read-write mode if a remount fails. Do
this only when you are sure no process will write to a filesystem while scanning.
-m Don't try to remount filesystem read-only. See comment with option -M.
-i Interactive mode. By default quotacheck exits when it finds an error. In interac-
tive mode user is asked for input instead. See option -n.
-n If the quota files become corrupted, it is possible for duplicate entries for a
single user or group ID to exist. Normally in this case, quotacheck exits or asks
user for input. When this option is set, the first entry found is always used (this
option works in interactive mode too).
Check quota for specified format (ie. don't perform format auto-detection). This is
recommended as detection might not work well on corrupted quota files. Possible
format names are: vfsold (version 1 quota), vfsv0 (version 2 quota), rpc (quota
over NFS), xfs (quota on XFS filesystem)
-a Check all mounted non-NFS filesystems in /etc/mtab
-R When used together with the -a option, all filesystems except for the root filesys-
tem are checked for quotas.
quotacheck should only be run by super-user. Non-privileged users are presumably not
allowed to read all the directories on the given filesystem.
quota(1), quotactl(2), fstab(5), quotaon(8), repquota(8), convertquota(8), setquota(8),
edquota(8), fsck(8), efsck(8), e2fsck(8), xfsck(8)
aquota.user or aquota.group
located at filesystem root with quotas (version 2 quota, non-XFS filesys-
quota.user or quota.group
located at filesystem root with quotas (version 1 quota, non-XFS filesys-
/etc/mtab names and locations of mounted filesystems
Jan Kara <email@example.com>
Based on old quotacheck by:
Edvard Tuinder <firstname.lastname@example.org>
Marco van Wieringen <email@example.com>
Fri Jul 20 2001 quotacheck(8)