Keeping Quotas Accurate

Whenever a file system is not unmounted cleanly (due to a system crash, for example), it is necessary to run quotacheck. However, quotacheck can be run on a regular basis, even if the system has not crashed. Safe methods for periodically running quotacheck include:

As root, place a shell script into the /etc/cron.daily/ or /etc/cron.weekly/ directory-or schedule one using the crontab -e command-that contains the touch /forcequotacheck command. This creates an empty forcequotacheck file in the root directory, which the system init script looks for at boot time. If it is found, the init script runs quotacheck. Afterward, the init script removes the /forcequotacheck file; thus, scheduling this file to be created periodically with cron ensures that quotacheck is run during the next reboot.

Refer to Automated Tasks for more information about configuring cron.

Running quotacheck in single user mode

An alternative way to safely run quotacheck is to (re-)boot the system into single-user mode to prevent the possibility of data corruption in quota files and run:

~]# quotaoff -vaug /<file_system>
~]# quotacheck -vaug /<file_system>
~]# quotaon -vaug /<file_system>

Running quotacheck on a running system

If necessary, it is possible to run quotacheck on a machine during a time when no users are logged in, and thus have no open files on the file system being checked. Run the command quotacheck -vaug <file_system> ; this command will fail if quotacheck cannot remount the given <file_system> as read-only. Note that, following the check, the file system will be remounted read-write.

Do not run quotacheck on a live file system

Running quotacheck on a live file system mounted read-write is not recommended due to the possibility of quota file corruption.

Refer to Automated Tasks for more information about configuring cron.