Reclaim KVM disk size
In KVM Hosts, we mostly used Sparse files, this could be qcow2 format or raw file. These files had certain features, most importantly thin thin-provisioning,so it grow as data stored in Guest Disk from inside Guest platform.
We just need to take care of final Disk size required for Guest, before Guest installation. Further Disk size will automatically grow when Guest grow.
But sometime when we free some space from Guest machine,it will not show in Host machine. In host machine Guest disk will continue grow. This is because free space from Guest is filled with binary zeros.
So it's annoying sometime that we are using less Disk space in Guest machine but still showing more Disk space in Host machine. It should occupy same space on host disk as used by Guest machine. For this we need to re-claim disk space.
In this video we would see how could we re-claim Disk space in KVM Guest machine. We will use qemu-img command for same.