System Administration Guide: Advanced Administration

Guidelines for Setting Up Quotas

Before you set up quotas, you need to determine how much space and how many inodes to allocate to each user. If you want to be sure that the total file system space is never exceeded, you can divide the total size of the file system between the number of users. For example, if three users share a 100-Mbyte slice and have equal disk space needs, you could allocate 33 Mbytes to each user.

In environments where not all users are likely to push their limits, you might want to set individual quotas so that they add up to more than the total size of the file system. For example, if three users share a 100-Mbyte slice, you could allocate 40 Mbytes to each.

When you have established a quota for one user by using the edquota command, you can use this quota as a prototype to set the same quota for other users on the same file system.

Before you turn on the quotas, you must first configure the UFS file systems for the quotas, establish quotas for each user, and run the quotacheck command to check for consistency between current disk usage and quota files. Also, if systems are rebooted infrequently, it is a good idea to periodically run the quotacheck command.

The quotas you set up with the edquota command are not enforced until you turn them on by using the quotaon command. If you have properly configured the quota files, the quotas are turned on automatically each time a system is rebooted and the file system is mounted.