5.1. Creating an LVM Logical Volume on Three Disks
5.1.1. Creating the Physical Volumes
To use disks in a volume group, you label them as LVM physical volumes.
This command destroys any data on /dev/sda1, /dev/sdb1, and /dev/sdc1.
[root@tng3-1 ~]# pvcreate /dev/sda1 /dev/sdb1 /dev/sdc1
Physical volume "/dev/sda1" successfully created
Physical volume "/dev/sdb1" successfully created
Physical volume "/dev/sdc1" successfully created
5.1.2. Creating the Volume Group
The following command creates the volume group new_vol_group.
[root@tng3-1 ~]# vgcreate new_vol_group /dev/sda1 /dev/sdb1 /dev/sdc1
Volume group "new_vol_group" successfully created
You can use the vgs command to display the attributes of the new volume group.
[root@tng3-1 ~]# vgs
VG #PV #LV #SN Attr VSize VFree
new_vol_group 3 0 0 wz--n- 51.45G 51.45G
5.1.3. Creating the Logical Volume
The following command creates the logical volume new_logical_volume from the volume group new_vol_group. This example creates a logical volume that uses 2GB of the volume group.
[root@tng3-1 ~]# lvcreate -L2G -n new_logical_volume new_vol_group
Logical volume "new_logical_volume" created
5.1.4. Creating the File System
The following command creates a GFS2 file system on the logical volume.
[root@tng3-1 ~]# mkfs.gfs2 -plock_nolock -j 1 /dev/new_vol_group/new_logical_volume
This will destroy any data on /dev/new_vol_group/new_logical_volume.
Are you sure you want to proceed? [y/n] y
Device: /dev/new_vol_group/new_logical_volume
Blocksize: 4096
Filesystem Size: 491460
Journals: 1
Resource Groups: 8
Locking Protocol: lock_nolock
Lock Table:
Syncing...
All Done
The following commands mount the logical volume and report the file system disk space usage.
[root@tng3-1 ~]# mount /dev/new_vol_group/new_logical_volume /mnt
[root@tng3-1 ~]# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/new_vol_group/new_logical_volume
1965840 20 1965820 1% /mnt
