How to resize LVM volumes on running machines

We describe here how to extend a volume on a running machine. Tested on a Juju controller (VM deployed by MAAS)

Link to the instructions used: https://www.rootusers.com/lvm-resize-how-to-increase-an-lvm-partition/

Procedure

1. Open virt-manager, select the VM

2. Add new hardware -> add storage

3. log onto the VM

4. fdisk -l -> identify the new device (e.g. /dev/vdb)

5. Initialize the device:

   # fdisk /dev/vdb -> add new partition /dev/vdb1 (key sequence: n, return, return, return, w)
   

6. Add the device in the logical volume group:

   # vgextend vgroot /dev/vdb1
   # vgdisplay -> you should see some free space
   
   --- Volume group ---
   VG Name               vgroot
   System ID
   ...
   VG Size               99.98 GiB
   PE Size               4.00 MiB
   Total PE              25596
   Alloc PE / Size       12797 / 49.99 GiB
   Free  PE / Size       12799 / 50.00 GiB
   
   # lvdisplay -> get LV path
     --- Logical volume ---
     LV Path                /dev/vgroot/lvroot
     LV Name                lvroot
     VG Name                vgroot
   
   # lvextend -l +100%FREE /dev/vgroot/lvroot
   # resize2fs /dev/vgroot/lvroot
   

That’s all!