Easily increase storage size with LVM

Your server needs more space eh? Throw another physical drive in there and let’s use that to increase the logical volume that needs more space! In this example, we are going to use a Citrix XenServer VPS running CentOS. We are going to increase the logical volume from 250gb to 300gb.

First, add the new storage to the machine. We used XenCenter to add a ‘virtual disk’ to the VPS. This step for you might be adding a new physical drive to the hardware machine. Either way, this step is the one where we put the new/blank storage somewhere so our Linux machine can see it…

Next, let’s see if the system can see the new storage:

Note: you’ll also see information about your current drives..

This tells us that Linux sees the storage but there is no partition table on it yet. let’s create a partition on the drive using fdisk, parted, cfdisk, etc.. and toggle it to type ‘8e’ (Linux LVM)

Now it should show up a little better in the fdisk -l command.

Next, create the physical volume on the new partition on the new drive:

Now, find out the volume group and logical volume names on your system. Make note of these..

We’ll assume that the information is:
Volume Group: test_vg
Logical Volume: test_lv

Now, use vgextend to add your new drive to the existing volume group:

You can see, by viewing ‘vgdisplay’ again, it will show you the added space:

Now, pull it across into the logical volume:

You’re almost home free! Now, vgdisplay shows the correct info and so does lvdisplay – but a simple df -h still shows the filesystem size has not changed. Let’s tell the filesystem to stretch out across the full logical volume:

And to see how it worked out:

It worked!