3.3. XFS Quota Management The XFS quota subsystem manages limits on disk space (blocks) and file (inode) usage. XFS quotas control or report on usage of these items on a user, group, or directory or project level. Also, note that while user, group, and directory or project quotas are enabled independently, group and project quotas are mutually exclusive. When managing on a per-directory or per-project basis, XFS manages the disk usage of directory hierarchies associated with a specific project. In doing so, XFS recognizes cross-organizational "group" boundaries between projects. This provides a level of control that is broader than what is available when managing quotas for users or groups. XFS quotas are enabled at mount time, with specific mount options. Each mount option can also be specified as noenforce ; this allows usage reporting without enforcing any limits. Valid quota mount options are: uquota / uqnoenforce : User quotas gquota / gqnoenforce : Group quotas pquota / pqnoenforce : Project quota Once quotas are enabled, the xfs_quota tool can be used to set limits and report on disk usage. By default, xfs_quota is run interactively, and in basic mode . Basic mode subcommands simply report usage, and are available to all users. Basic xfs_quota subcommands include: quota username/userID Show usage and limits for the given username or numeric userID df Shows free and used counts for blocks and inodes. In contrast, xfs_quota also has an expert mode . The subcommands of this mode allow actual configuration of limits, and are available only to users with elevated privileges. To use expert mode subcommands interactively, use the following command: Expert mode subcommands include: report /path Reports quota information for a specific file system. limit Modify quota limits. For a complete list of subcommands for either basic or expert mode, use the subcommand help . All subcommands can also be run directly from a command line using the -c option, with -x for expert subcommands. Example 3.2. Display a Sample Quota Report For example, to display a sample quota report for /home (on /dev/blockdevice ), use the command xfs_quota -x -c 'report -h' /home . This displays output similar to the following: To set a soft and hard inode count limit of 500 and 700 respectively for user john , whose home directory is /home/john , use the following command: In this case, pass mount_point which is the mounted xfs file system. By default, the limit subcommand recognizes targets as users. When configuring the limits for a group, use the -g option (as in the example). Similarly, use -p for projects. Soft and hard block limits can also be configured using bsoft or bhard instead of isoft or ihard . Example 3.3. Set a Soft and Hard Block Limit For example, to set a soft and hard block limit of 1000m and 1200m, respectively, to group accounting on the /target/path file system, use the following command: Note The commands bsoft and bhard count by the byte. Important While real-time blocks ( rtbhard / rtbsoft ) are described in man xfs_quota as valid units when setting quotas, the real-time sub-volume is not enabled in this release. As such, the rtbhard and rtbsoft options are not applicable. Setting Project Limits With XFS file system, you can set quotas on individual directory hierarchies in the file system that are known as managed trees. Each managed tree is uniquely identified by a project ID and an optional project name . Add the project-controlled directories to /etc/projects . For example, the following adds the /var/log path with a unique ID of 11 to /etc/projects . Your project ID can be any numerical value mapped to your project. Add project names to /etc/projid to map project IDs to project names. For example, the following associates a project called logfiles with the project ID of 11 as defined in the step. Initialize the project directory. For example, the following initializes the project directory /var : Configure quotas for projects with initialized directories: Generic quota configuration tools ( quota , repquota , and edquota for example) may also be used to manipulate XFS quotas. However, these tools cannot be used with XFS project quotas. Important Red Hat recommends the use of xfs_quota over all other available tools. For more information about setting XFS quotas, see man xfs_quota , man projid(5) , and man projects(5) .

Commands:
xfs_quota -x
User quota on /home (/dev/blockdevice) Blocks User ID Used Soft Hard Warn/Grace ---------- --------------------------------- root 0 0 0 00 [------] testuser 103.4G 0 0 00 [------]
xfs_quota -x -c 'limit isoft=500 ihard=700 john' /home/
xfs_quota -x -c 'limit -g bsoft=1000m bhard=1200m accounting' /target/path
echo 11:/var/log >> /etc/projects
echo logfiles:11 >> /etc/projid
xfs_quota -x -c 'project -s logfiles' /var
xfs_quota -x -c 'limit -p bhard=lg logfiles' /var