What is Disk Quota ?

Disk space can be restricted by implementing disk quotas which alert a system administrator before a user consumes too much disk space or a partition becomes full. Disk quotas can be configured for individual users as well as user groups.

In addition, quotas can be set not just to control the number of disk blocks consumed but to control the number of inodes (data structures that contain information about files in UNIX file systems). Because inodes are used to contain file-related information, this allows control over the number of files that can be created.

Configuring Disk Quota

To implement disk quotas, use the following steps:

1. Enable quotas per file system by modifying the /etc/fstab file.

2. Remount the file system(s).

3. Create the quota database files and generate the disk usage table.

4. Assign quota policies.

Applying Disk Quota

• Step 1 - Open /etc/fstab file using vi editor
• vi /etc/fstab
• Step 2 - Add usrquota or grpquota to following line
• LABEL=/home /home ext3 defaults,usrquota 0 0
• Step 3 – Remount the /home folder or reboot your machine
• mount –o remount /home
• Step 4 – Create quota database file
• quotacheck –cug /home

• quotaon -vug /home
• Step 5 – Apply the quota to a user / group using following command
• edquota –u username
• or
• setquota -u username softHDDlimit hardHDDlimit softINODElimit hardINODElimit /location

Quota Commands

• quota : Run by user to check quota status
• repquota : Run by the root user to check the quota status for every user
• edquota –t : Assigns the grace period
• edquota -g groupname : Assigning Quotas on Group
• quotaoff -vaug : Disabling quota on everyone
• quotaon -vaug : Enabling quota on eve