Resizing the file system size is an important task of Linux admin’s profile. In Linux , LVM(Logical Volume Manager) provides the facility to increase and reduce the file system size. In this tutorial we will discuss the practical examples of lvextend and will learn how to extend LVM partition on the fly using lvextend command.
Scenario : Suppose we have a LVM partition(/home) and running out of space and want to extend or increase file system size. So to increase the size of the file system first we must see whether in volume group has free space or not. If the Volume group has free space then use the below steps :
Step:1 Type ‘ df -h’ command to list the file system
Run the “df -h” command followed by the file system to view total ,used and available disk space
[[email protected] home]# df -h /home/ Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cloud-LogVol00 9.7G 9.2G 0 100% /home
As we can see /home is 100 % utilized.
Step:2 Now check whether free space is available space in the volume group
To display volume group details, execute the vgdisplay command followed by volume group name,
# vgdisplay < Volume-Group-Name>
[[email protected] home]# vgdisplay vg_cloud --- Volume group --- VG Name vg_cloud System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 4 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 1 Act PV 1 VG Size 27.01 GiB PE Size 4.00 MiB Total PE 6915 Alloc PE / Size 5256 / 20.53 GiB Free PE / Size 1659 / 6.48 GiB VG UUID 1R89GB-mIP2-7Hgu-zEVR-5H02-7GdB-Ufj7R4
Step:3 Use lvextend command to increase the size.
Run below lvextend command to extend the file system,
[[email protected] ~]# lvextend -L +2G /dev/mapper/vg_cloud-LogVol00 Extending logical volume LogVol00 to 11.77 GiB Logical volume LogVol00 successfully resized
Above command will extend the file system size by 2GB. You can also specify the size in MB , just replace G with M.
Step:3 Run the resize2fs command
In above step we have executed the lvextend command to extend the file system size by 2 GB but still the file system is not updated, so execute the following resize2fs command
[[email protected] ~]# resize2fs /dev/mapper/vg_cloud-LogVol00
Step:4 Use df command and verify /home size .
Re-run the df -h command followed by /home file system, now we can see that file system has been extended by 2 GB, before the extension size was 10 GB
[[email protected] ~]# df -h /home/ Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_cloud-LogVol00 12G 9.2G 1.9G 84% /home