System Administration Guide: Advanced Administration (2024)

Guidelines for Setting Up Quotas

Before you set up quotas, you need to determine how much space and howmany inodes to allocate to each user. If you want to be sure that the totalfile system space is never exceeded, you can divide the total size of thefile system between the number of users. For example, if three users sharea 100-Mbyte slice and have equal disk space needs, you could allocate 33 Mbytesto 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 thetotal size of the file system. For example, if three users share a 100-Mbyteslice, 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 thesame quota for other users on the same file system.

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

The quotas you set up with the edquota command arenot enforced until you turn them on by using the quotaoncommand. If you have properly configured the quota files, the quotas are turnedon automatically each time a system is rebooted and the file system is mounted.

How to Configure File Systems for Quotas

1. Become superuser.

2. Edit the /etc/vfstab file and add rqto the mount options field for each UFS file system thatwill have quotas.

3. Change directory to the root of the file system that will have quotas.

   See Also

   What Is a Quota?Check Disk Quota and UsageOpenStack Docs: OpenStack services loggingQuotas: Example, Types & Difference

4. Create a file named quotas.

   # touch quotas

5. Change permissions to read/write for root access only.

   # chmod 600 quotas

Examples--Configuring File Systems for Quotas

The following /etc/vfstab example shows that the /export/home directory from the system plutois mounted as an NFS file system on the local system. You can tell quotasare enabled by the rq entry under the mount options column.

#device device mount FS fsck mount mount#to mount to fsck point type pass at boot options#pluto:/export/home - /export/home nfs - yes rq

The following example line from /etc/vfstab showsthat the local /work directory is mounted with quotasenabled, signified by the rq entry under the mount options column.

#device device mount FS fsck mount mount#to mount to fsck point type pass at boot options#/dev/dsk/c0t4d0s0 /dev/rdsk/c0t4d0s0 /work ufs 3 yes rq

How to Set Up Quotas for a User

1. Become superuser.

2. Use the quota editor to create a temporary file that contains one lineof quota information for each mounted UFS file system that has a quotas file in the file system's root directory.

   # edquota username

   Where username is the user for whom you wantto set up quotas.

3. Change the number of 1-Kbyte disk blocks (both soft and hard) and thenumber of inodes (both soft and hard) from 0 (the default) to the quotas youspecify for each file system.

   See Also

   OpenStack Docs: Manage Compute service quotas

4. Verify the user's quota.

   # quota -v username

   -v	Displays the user's quota informationon all mounted file systems where quotas exist.
   username	Specifies the user name to view quotalimits.

Examples--Setting Up Quotas for a User

The following example shows the contents of the temporary file openedby edquota on a system where /filesis the only mounted file system containing a quotas filein the root directory.

fs /files blocks (soft = 0, hard = 0) inodes (soft = 0, hard = 0)

The following example shows the same line in the temporary file afterquotas have been set up.

fs /files blocks (soft = 50, hard = 60) inodes (soft = 90, hard = 100)

How to Set Up Quotas for Multiple Users

1. Become superuser.

2. Use the quota editor to apply the quotas you already established fora prototype user to the additional users you specify.

   # edquota -p prototype-user username ...

   prototype-user	User name of the account for whichyou have set up quotas.
   username ...	Specifies one or more user names ofadditional accounts.

Example--Setting Up Prototype Quotas for Multiple Users

The following example shows how to apply the quotas established foruser bob to users mary and john.

# edquota -p bob mary john

How to Check Quota Consistency

Note - To ensure accurate disk data, the file systems being checked shouldbe quiescent when you run the quotacheck command manually.The quotacheck command is run automatically when a systemis rebooted.

1. Become superuser.

2. Run a consistency check on UFS file systems.

   # quotacheck [-va] filesystem

   -v	(Optional) Identifies the disk quotasfor each user on a particular file system.
   -a	Checks all file systems with an rq entry in the /etc/vfstab file.
   filesystem	Specifies the file system to check.

   See quotacheck(1M)for more information.

Example--Checking Quota Consistency

The following example shows how to check quotas for the /export/home file system on the /dev/rdsk/c0t0d0s7 slice.The /export/home file system is the only file systemwith an rq entry in the /etc/vfstabfile.

# quotacheck -va*** Checking quotas for /dev/rdsk/c0t0d0s7 (/export/home)

How to Turn On Quotas

1. Become superuser.

2. Turn on file system quotas.

   # quotaon [-v] -a filesystem ...

   -v	Displays a message for each file systemafter quotas are turned on.
   -a	Turns on quotas for all file systemswith an rq entry in the /etc/vfstabfile.
   filesystem ...	Turns on quotas for one or more filesystems that you specify. More than one file system is specified by separatingeach file system name with a space.

Example--Turning On Quotas

The following example shows how to turn quotas on for the file systemson the /dev/dsk/c0t4d0s7 and /dev/dsk/c0t3d0s7 slices.

# quotaon -v /dev/dsk/c0t4d0s7 /dev/dsk/c0t3d0s7/dev/dsk/c0t4d0s7: quotas turned on/dev/dsk/c0t3d0s7: quotas turned on

After you have set up and turned on disk quotas and inode quotas, youcan check for users who exceed their quotas. In addition, you can check quotainformation for entire file systems.

The following table describes the commands you use to check quotas.

Table 17-2 Commands for Checking Quotas