‘edquota’ and the ‘quota’ family tool

This post is in conjunction with the “the ‘dd’ way” post I made some weeks ago. The problem arose when we needed to control the hard disk space usage of some users in our IBM p5 server. Our setup was a client-server type where the clients are thin clients . The problem that plagued us was that some users saved files that were too large that other users ran out of hard disk space. This is obviously a problem, and being a Linux user/admin, I/we had to simply find a way.

Luckily for us, there’s the ‘quota’ family of tools for adding, applying, editing and restricting user hard disk space consumption. If you’re using Ubuntu, any Debian based Linux distribution, or if you just like to use

apt-get

, you can easily get the quota family of tools by issuing:

sudo apt-get install quota

Usually, Linux distros have the quota family of tools in their main repositories, so this shouldn’t be a problem.
Quotas are applied on a file-system basis. This means that if you have for example a partition in your hard drive, mounted in /media/hdb4, you can create separate quotas for another partition, say /media/hdc1.
You can enable quotas on your partitions by adding the

usrquota

and

grpquota

mount options on your

/etc/fstab

file. To do this, open

/etc/fstab

using you preferred text editor and edit it so it looks something like:

/dev/sda3            /                    ext3       acl,user_xattr,usrquota,grpquota        1 1

If you haven’t edited or bothered to wonder about your

/etc/fstab/

you don’t have to worry (or edit it for that matter) at this time. All you need to know is that you want to add quotas on your partition (in the previous example, /dev/sda3) by adding the mount options

usrquota

and

grpquota

.
After adding the mount options you need to remount your partitions where you added the

usrquota

and

grpquota

options so you can finally apply quotas.

sudo mount -o remount /dev/sda3

The previous command only remounts the specified partition, so you won’t need to reboot in order for the quota options to be applied. To check if the quota options were successfully applied, enter the command:

mount | grep quota

. You should see an output similar to this:

/dev/sda3 on / type ext3 (rw,acl,user_xattr,usrquota,grpquota)

You can then issue

quotacheck

especially if you’ve applied quotas before, to prepare for the final step which is

sudo quotaon -augv

which tries to turn all quotas for all user and group quotas, and be verbose about it. One other thing I usually do (most often actually) is to use this command instead:

sudo /etc/init.d/quota start

which I think is more convenient.
How to apply individual quotas to users/groups
To add a hard disk limit (or quota) to user eee13_200366176 in our server, I use the command

sudo edquota -u eee13_200366176

The previous command opens a text editor (usually Vi or Vim by default). In this case I want to limit this user’s hard disk space to only 200 MB, as there will be dozens of students for dozens of courses. Once the text editor opens, the initial output (assuming there weren’t any quotas previously) should look like this:

Disk quotas for user eee13_200366176 (uid 1200):
  Filesystem                   blocks       soft       hard     inodes     soft     hard
  /dev/sda3                       224          0     0         42        0        0

Which means that the user is currently using ony 224 KB on his/her account. I edit it to look like so, in order to impose a 200 MB hard disk limit:

Disk quotas for user eee13_200366176 (uid 1200):
  Filesystem                   blocks       soft       hard     inodes     soft     hard
  /dev/sda3                       224          0     200000         42        0        0

You can check the other options and parameters used by the quota family by reading its man page.
Finally, to apply the quota I placed, save the file you edited and exit. Don’t worry about the spacing/indentation, the file will be automatically indented to the proper positions after you save and exit. Then again use the command

/etc/init.d/quota start

to turn on the quotas. To check the fruit of your labors, enter

repquota -a

and you should see an output such as this:

eee13_199703431 --   29320       0  200000           1751     0     0
eee13_200004928 --   20632       0  200000            712     0     0
eee13_200346669 --   36112       0  200000           2630     0     0
eee13_200366176 --     224       0  200000             42     0     0
eee13_200402395 --    6168       0  200000            274     0     0
eee13_200411066 --   11116       0  200000            588     0     0
eee13_200411386 --   10796       0  200000            331     0     0
eee13_200414739 --   14268       0  200000            386     0     0
eee13_200436040 --   16260       0  200000            352     0     0
eee13_200438007 --    9096       0  200000            273     0     0
........
eee13_200366176 --     224       0  200000             42     0     0

And there we have it. The user whose quota we edited has a 200 MB limit now. Now you can test/check if the quota works by reading and following my previous post about the

dd

tool. If you have comments and suggestions, please do post them. In the next few days I’ll create a script to automate all of these.