LVM in Linux ( RHEL CENTOS UBUNTU DEBIAN )

Make four partitions of size 100M, 50M, 75M and 150M with partition ID 8e. 8e is the ID of LVM type partition.

Suppose the newly created partitions are:  /dev/hda10, /dev/hda11, /dev/hda12, /dev/hda13.

Now create Physical Volume:

#pvcreate  /dev/hda10

#pvcreate  /dev/hda11

#pvcreate  /dev/hda12

#pvcreate /dev/hda13

To check status of pv:

#pvscan

#pvdisplay

Now create volume group:

#vgcreate  vg01  /dev/hda10  /dev/hda11

#vgcreate vg02  /dev/hda12  /dev/hda13

To check status of vg:

#vgscan

#vgdisplay

Now create logical volume:

#lvcreate   --name   lv1  --size  110M vg01

#lvcreate   --name   lv2  --size  170M vg02

To check status of lv:

#lvscan

#lvdisplay

Now need to format these newly created logical volume with ext3 filesystem

#mkfs.ext3   /dev/vg01/lv1

#mkfs.ext3  /dev/vg02/lv2

Now mount the logical volumes to folder:

#mkdir   /raidtest1

#mkdir  /raidtest2

# mount   /dev/vg01/lv1  /raidtest1

#mount   /dev/vg02/lv2  /raidtest2

#df –h

Now we will extend or reduce our volume size: (Unmount first)

For extending:

#umount  /raidtest1

#lvextend  -L +15M /dev/vg01/lv1

#e2fsck  -f  /dev/vg01/lv1

#resize2fs /dev/vg01/lv1

For reducing:

#umount  /raidtest2

#dumpefs  /dev/vg02/lv2 | grep –I ‘Block size’

#e2fsck  -f  /dev/vg02/lv2

#resize2fs /dev/vg02/lv2  143360

#lvreduce  -L  -140M  /dev/vg02/lv2

Other commands(need to delete associated lv first to do something on vg, need to delete associated vg fisrt to do something on pv):

#lvrename   vg01   lv1    lv3

#lvrename   vg02   lv2    lv4

#lvremove   /dev/vg01/lv3

#lvremove  /dev/vg02/lv4

#vgrename  vg01   vg03

#vgrename  vg02   vg04

#vgremove  vg03

#vgremove  vg04

#pvremove  /dev/hda10

#pvremove  /dev/hda11

#pvremove  /dev/hda12

#pvremove  /dev/hda14