You are Here:   FAQ->Dedicated Servers->Linux Root Server->Article #11


How can I increase a logical volume?


Step 1 First, log into the server via SSH.
Step 2 Once logged in, type df - h at the command prompt and hit ENTER. The partition and logical volume sizes will be listed including the used disk space. In the image below, the var logical volume is 4GB. Assume that ~9GB of web content will be uploaded to the /var folder. The disk space needs to be increased before there is enough space to upload the content.

Further Explanation:
df arrow image This is the disk free space command which will display disk usage information.
-h arrow image This option forces the output to be in human readable format. This will display sizes in KB, MB or GB.

lvGrow1.png
Step 3 Next, type fdisk -l to view the total hard disk(s) size and partitions on the disk. It can also be noticed here that the physical partition /dev/sda3 is using Linux LVM.

lvGrow2.png
Step 4 Type the pvs command and press Enter.

Further Explanation:
pvs arrow image Physical Volume Show command.
PV arrow image Physical Volume path
VF arrow image Volume Group name.
Fmt arrow image LVM Format
Attr arrow image Physical volume attributes. The a attribute means that the physical volume is allocatable and not read-only.
PSize arrow image Physical Size of the physical volume.
PFree arrow image Physical Free space left on the physical volume.

lvGrow3.png
Step 5 As stated above, our scenario requires roughly 9GB of data to be uploaded to the /var folder. Since the logical volume assigned to /var is only 4GB, we will increase this to 10GB using the lvextend command. The command below is to be used as reference only as the parameters will be different depending on your scenario.

The format for the lvextend command is as follows:
lvextend -L +1G /dev/mapper/vg00-var

Further Explaination:
lvextend arrow image This is the logical volume extend command used to make a logical volume larger.
-L +6G arrow image It is specified using the Logical volume size option, how much larger to make the volume. In this scenario, 6 gigabytes is added to the current 4 gigabyte volume to result in a 10 gigabyte volume.
/dev/mapper/vg00-var arrow image The path to the logical volume is specified last. The path to the volume to be extended was taken from the output from the second step in this guide.

lvGrow4.png
Step 6 Type df -h to display the disk free space once again. The lvextend operation finished successfully in the last step however the /dev/mapper/vg00-var size is still only showing 4.0G. This is because while the logical volume was increased successfully, the file system needs to be extended to take advantage of the full space of the logical volume.

lvGrow5.png
Step 7 Type lvs to show the logical volume information once again. Here, we can confirm that the logical volume has successfully been extended to 10 gigabytes. In the next steps, we will increase the file system to match the logical volume size.

lvGrow6.png
Step 8 Type mount and press ENTER to display the mounted file systems. From the output, we find that the /dev/mapper/vg00-var logical volume is using xfs.

lvGrow7.png
Step 9 To increase the file system to match that of the logical volume, we will use the xfs_growfs command.

Typing xfs_growfs /var will extend the file system to the 10 gigabyte limit of the logical volume.

lvGrow8.png
Step 10 Type df -h to display the disk free space to confirm that the file system has been extended.

lvGrow9.png


Print Article
How useful was this article?
(From 5 = Very Useful to 1 = Not Very Useful at all):
1 2 3 4 5