When running virtual machines in unRaid (or on any virtualization management server), you sometimes run out of space and need to extend the virtual disk (vdisk) of the VM. This is a guide on how to do that (for Ubuntu, LVM-based VMs).

Extend the vdisk on unRaid

  • open terminal
  • navigate to the vdisk, usually /mnt/user/domains/<VM name>/vdisk1.img
  • extend via qemu-img resize vdisk1.img +200G or whatever size you want to extend it to

Make the VM recognize the vdisk change

I have found this article to be most useful in extending the logical volume on the VM