Linux disk quotas are used to limit a user's or a group of users' ability to consume disk space. Linux disk quotas prevents a user or a group from using disk storage more than what expected and denying other users the disk storage space.
Enabling Linux Disk Quotas per filesystem
To use Linux disk quotas, they must be enabled in /etc/fstab configuration file. To add quota option in /etc/fstab, following syntax can be used.
/dev/sdb1 /home ext3 defaults,usrquota,grpquota 0 0
The usrquota mount option enables user quotas, and the grpquota option enables group quotas. One or both can be used. Reboot the machine to make the changed effect or remount using mount command. Use the Linux mount command to confirm the user quota and group quota are enabled.
How to use the mount comand with remount option is shown below.
root@RHEL2 ~]# mount –o remount /dev/sdb1