Table of Content
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Description: Candidates should be able to manage disk quotas for users.
Key Knowledge Areas:
- Set up a disk quota for a filesystem
- Edit, check and generate user quota reports
Terms and Utilities:
quota edquota repquota quotaon
quota
root@dclab-u1504s:/home/oldhorse# which quota /usr/bin/quota root@dclab-u1504s:/home/oldhorse# which quotaon /sbin/quotaon root@dclab-u1504s:/home/oldhorse# cat /etc/fstab /dev/sdb /myspace ext3 defaults 1 3 change to /dev/sdb /myspace ext3 defaults,usrquota,grpquota 1 3 root@dclab-u1504s:/home/oldhorse# umount /myspace root@dclab-u1504s:/home/oldhorse# mount -a root@dclab-u1504s:/home/oldhorse# mount|grep quota /dev/sdb on /myspace type ext3 (rw,relatime,quota,usrquota,grpquota,data=ordered)
convert sdb from ext3 to ext4
umount /myspace fsck.ext3 -pf /dev/sdb tune2fs -O extents,uninit_bg,dir_index /dev/sdb fsck.ext4 -yfD /dev/sdb
quotaon ext4
quotacheck -augvc quotacheck: Scanning /dev/sdb [/myspace] done quotacheck: Checked 2 directories and 2 files quotaon -p /myspace/ group quota on /myspace (/dev/sdb) is off user quota on /myspace (/dev/sdb) is off quotaon -uagv /dev/sdb [/myspace]: group quotas turned on /dev/sdb [/myspace]: user quotas turned on quotaon -p /myspace/ group quota on /myspace (/dev/sdb) is on user quota on /myspace (/dev/sdb) is on
edquota
edquota -u oldhorse default editor nano, ctrl-x to exit
check quota
/myspace$ dd if=/dev/zero of=/myspace/testfile1 bs=1024 count=1024
1024+0 records in
1024+0 records out
1048576 bytes (1.0 MB) copied, 0.00322465 s, 325 MB/s
/myspace$ ls -lh
total 1.1M
-rw------- 1 root root 7.0K Oct 17 09:18 aquota.group
-rw------- 1 root root 7.0K Oct 17 09:18 aquota.user
drwx------ 2 oldhorse oldhorse 16K Oct 4 03:56 lost+found
-rw-rw-r-- 1 oldhorse oldhorse 1.0M Oct 17 09:43 testfile1
quota
Disk quotas for user oldhorse (uid 1000):
Filesystem blocks quota limit grace files quota limit grace
/dev/sdb 1044 10240 11264 3 50 50
dd if=/dev/zero of=/myspace/testfile2 bs=1024 count=9500
9500+0 records in
9500+0 records out
9728000 bytes (9.7 MB) copied, 0.0469966 s, 207 MB/s
quota
Disk quotas for user oldhorse (uid 1000):
Filesystem blocks quota limit grace files quota limit grace
/dev/sdb 10544* 10240 11264 7days 4 50 50
oldhorse@dclab-u1504s:/myspace$ ls -lh
total 11M
-rw------- 1 root root 7.0K Oct 17 09:18 aquota.group
-rw------- 1 root root 7.0K Oct 17 09:18 aquota.user
drwx------ 2 oldhorse oldhorse 16K Oct 4 03:56 lost+found
-rw-rw-r-- 1 oldhorse oldhorse 1.0M Oct 17 09:43 testfile1
-rw-rw-r-- 1 oldhorse oldhorse 9.3M Oct 17 09:43 testfile2
sudo repquota -ug /myspace/
[sudo] password for oldhorse:
*** Report for user quotas on device /dev/sdb
Block grace time: 7days; Inode grace time: 7days
Block limits File limits
User used soft hard grace used soft hard grace
----------------------------------------------------------------------
oldhorse +- 10544 10240 11264 6days 4 50 50
*** Report for group quotas on device /dev/sdb
Block grace time: 7days; Inode grace time: 7days
Block limits File limits
Group used soft hard grace used soft hard grace
----------------------------------------------------------------------
oldhorse -- 10544 0 0 4 0 0
warn email for over quota
cat /etc/quotagrpadmins cat /etc/warnquota.conf cat /etc/quotatab sudo warnquota /bin/sh: 1: /usr/sbin/sendmail: not found warnquota: Warning: Mailer exitted abnormally.
Quiz questions
1. Name 2 Linux filesystems that support quotas, and name one filesystem that does not. 2. What happens when the soft limit is reached? 3. What happens when the hard limit is reached? 4. Who can adjust filesystem quotas? 5. If changes are made to the filesystem while quotas are not enabled, which command must be used for quotas to work correctly? Answers to quiz questions 1. reiserfs does not support quotas in some kernel versions. Ext2, ext3 and others do support quotas. Readonly file systems do not support quotas. 2. Nothing happens. quota -q begins to display a warning message. 3. The filesystem behaves as if it is full. 4. Only root. 5. quotacheck -avug (or specify the specific filesystem)