Extend an LVM volume

After the disk or the partition that holds the physical volume grows, LVM does not pick up the extra space by itself. Extend each layer from the bottom up: physical volume, logical volume, filesystem.

After a VPS upgrade the disk is expanded automatically; this guide is for the cases where that did not happen, or where you resized the disk yourself.

WARNING

Back up critical data before you change disks, partitions or LVM metadata. A mistake at any layer can make the volume unmountable.

Find the names on your system

Confirm the actual names before running anything below:

lsblk
sudo pvs
sudo vgs
sudo lvs

The rest of this guide uses a typical Ubuntu install:

Disk	/dev/sda
LVM partition	/dev/sda3
Volume group	ubuntu-vg
Logical volume	ubuntu-lv
Mount point	/

Step 1: confirm the OS sees the new size

lsblk

If the disk reports the new size and the partition does not, grow the partition first (growpart, parted, or fdisk) before continuing.

Step 2: resize the physical volume

sudo pvresize /dev/sda3

Confirm there is now free space inside the volume group:

sudo vgs

The VFree column should be non-zero.

Step 3: extend the logical volume

To use all available free space:

sudo lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv

Or to grow by a specific amount, e.g. 20 GiB:

sudo lvextend -L +20G /dev/mapper/ubuntu--vg-ubuntu--lv

Step 4: resize the filesystem

ext4:

sudo resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv

xfs (online resize, mount path):

sudo xfs_growfs /

Step 5: verify

df -h
sudo pvs
sudo vgs
sudo lvs

The mount point should now report the new size. If lsblk still shows the old partition size, the disk-level resize step was not picked up - confirm with dmesg | tail or reboot.