quotacheck is a command-line utility that is used to scan a file system for disk usage and create, check, and repair quota files. A quota file is a system file that tracks the disk usage of individual users or groups on a file system. Quotas are typically used in multi-user environments where multiple users share a common file system and there is a need to limit the amount of disk space that each user can consume.
quotacheck works by scanning the file system and generating a list of disk usage information for each user or group. This information is then used to create or update the quota files. The tool also provides options for checking and repairing existing quota files.
One important consideration when running quotacheck is that it is best to run the tool with quotas turned off to prevent damage or loss to the quota files. Quotas should only be turned on after the quotacheck process has completed successfully.
quotacheck Command Examples
1. Check quotas on all mounted non-NFS filesystems:
# sudo quotacheck --all
2. Force check even if quotas are enabled (this can cause damage or loss to quota files):
# sudo quotacheck --force mountpoint
3. Check quotas on a given filesystem in debug mode:
# sudo quotacheck --debug mountpoint
4. Check quotas on a given filesystem, displaying the progress:
# sudo quotacheck --verbose mountpoint
5. Check user quotas:
# sudo quotacheck --user user mountpoint
6. Check group quotas:
# sudo quotacheck --group group mountpoint
Summary
Overall, quotacheck is a useful tool for managing disk space usage on multi-user file systems. By using quotas, administrators can ensure that disk space is allocated fairly among users and prevent any one user from consuming an excessive amount of space.