User Quota and group quota

User Quota

Monitoring and controlling disk space usage is another important part of a system administrator tasks. User quota is used to restrict the amount of disk space on each partition by each user.

Steps 

Edit the file /etc/fstab

# vi /etc/fstab

Search the following line

“LABEL=/home        /home             etx3                 defaults           1 2”

Just add ‘usrquota’ after the word ‘defaults” as

“LABEL=/home        /home             ext3                 defaults,usrquota       1 2”

Remount the home partition

# mount –o remount /home

Where –o I used to active comma separator used in fstab

After given a quota we must remount the directory with user quota or if we restart the system , it automatically remount.

Now check the mount quota

# quotacheck –avum

Where

            -a : Scan file system with quota enabled

            -v : Verbose mode

            -u : Scan for user quota

            -m : Remount file system with quota enabled

Now check the /home

#cd /home

#ls

File aquota.user will created)

Now add quota for particular user

# edquota –u username

Output of this command

File System      Block   soft      hard    inode   soft      hard

/dev/hda2     24       0         0           9          0          0

1 block=1Kbyte

Suppose we set the userquota by block size i.e we set the soft limit to 3000 and Hard limit to 4000 i.e. 3M and 4M

/dev/hda2     25        3000    4000       9          0          0

Block and inode has a grace period of 7 days ( by default)

We can set the quota either by setting blocks soft and hard limit of inode ( Number of maximum file created)

Make the quota on

# quotaon /home

We can generate the quota information

#repquota /home

Note:

We can generate the file of big size to check the quota

Syntax:

#dd if=/dev/zero of=bigfile bs=1M count=3

To check the quota for particular user after login

#quota

To set the grace period for particular user

#edquota –T username

To assign quota of one user to another user

#edquota –p user1 user2

We can also set the quota for particular user by using following command.

#setquota  -u username 2000 3000 20 25 /home

Group quota

Group quota is use for limted spase to all user in group wise

Create a partations and mount this partations in /etc/fstab.

Create data base in /etc/fstab for group

#vim /etc/fstab

/dev/hda5     /dirname        ext3     defaults,grpquota 0 0

:wq

#mount –a

# quotacheck –g /dirname

now check the database in directory

#cd /dirname

#ll

 rwx-r-w-r---   root     root     aquota.group

#quotaon –vg /dirname

Create Group:----

#groupadd    jetking   (group name Jetking)

Create user in group

#useradd   –G    jetking   username

This command is use for add existing user in created group.

#usermod  -G    jetking   oldusername

#cat /etc/group     This command is use for check the group and user

For change group

#chgrp  jetking   /dirname

Give full permission

#chmod  2770   /dirname

For edit quota

#edquota  -g   jetking     (group name)

   soft         hard      (soft warning, hard limt)

:wq

#repquota   -avg   (This command use for check quota)

change user secondary group

#cd   /home

#chgrp   jetking     usrename

Now login user and goto directory and check quota..