In this post, I will explain how to expand disk space on a Linux system using Logical Volume Manager (LVM). Whether you’re dealing with a physical or virtual disk, this step-by-step tutorial will help you make the most of your storage without the need for a system reboot.
Step 1: Increase Disk Size
The first step is to increase the size of the disk that your Linux OS uses. This can be done by expanding the virtual disk in virtualization platforms like VMWare, KVM or Hyper-V. For this post, we’ll extend a 16 GB disk to 30 GB.
My Lab Details:
Hypervisor: VMware ESXi
VM: Ubuntu 22.04.1 LTS
root@ubuntu-test:~# df -h Filesystem Size Used Avail Use% Mounted on tmpfs 98M 1.3M 96M 2% /run /dev/mapper/ubuntu--vg-ubuntu--lv 9.8G 6.7G 2.6G 73% / tmpfs 486M 0 486M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock /dev/sda2 1.7G 247M 1.4G 16% /boot tmpfs 98M 4.0K 98M 1% /run/user/1000
Disk is still not visible/listed
Step 2: Rescan the Disk
After resizing the disk, you may need to prompt Linux to recognize the additional free space. To check for free space, run the
cfdisk command and see if it lists free space. Use “q” to exit when done. If there’s no free space listed, initiate a rescan for
/dev/sda with the command:
echo 1 > /sys/class/block/sda/device/rescan
Once done, rerun
cfdisk, and you should now see the free space.
Step 3: Resize the Partition
/dev/sda3 partition from the list and choose “Resize” from the menu. Hit ENTER and confirm the new size. Then select “Write,” type “yes” to confirm, and hit ENTER. Finally, use “q” or select quit to exit the program. Your
/dev/sda3 partition should now reflect the new, larger size.
Step 4: Extend the Physical Volume (PV)
With the LVM partition backing up the
/dev/sda3 PV extended, it’s time to extend the PV itself.
to accomplish this, and then use
pvdisplay to verify the new size. In our example, the PV has increased from 14.2GB to 28.2G.
Step 5: Check Volume Group (VG) Free Space
Now, check the VG’s free space using
vgdisplay. In our case, there’s 18.25 GiB of free space available within the VG.
Step 6: Extend Logical Volume (LV)
lvdisplay to verify the size of your upstream Logical Volume (LV). Extend the LV to use all available VG free space with the below command
lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv
Check the LV one more time with
lvdisplay to ensure it’s been extended.
root@ubuntu-test:~# lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv Size of logical volume ubuntu-vg/ubuntu-lv changed from 10.00 GiB (2560 extents) to <28.25 GiB (7231 extents). Logical volume ubuntu-vg/ubuntu-lv successfully resized. root@ubuntu-test:~# lvdisplay --- Logical volume --- LV Path /dev/ubuntu-vg/ubuntu-lv LV Name ubuntu-lv VG Name ubuntu-vg LV UUID xL1oCY-qBRL-cT86-jRRr-0cWK-0P4W-U0Y1Dp LV Write Access read/write LV Creation host, time ubuntu-server, 2023-04-12 11:44:17 +0000 LV Status available # open 1 LV Size <28.25 GiB Current LE 7231 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0
Step 7: Resize the File System
At this point, the block volume supporting your root filesystem has been expanded, but the filesystem itself needs resizing. Run
df -h to check the current filesystem size. Use the below command to resize it, and run
df -h once more to confirm the new available space.
Following the above steps, you can successfully expand your Linux Machine/VM physical or virtual disk space using LVM. This allows you to efficiently manage your storage resources and accommodate growing storage needs without disrupting your system. Hope this helps.