Image files on qcow2 format with KVM

Hi all,
my KVM, on Centos 6.3, make all virtual machines with .img disk files format.
I would like that KVM is able to make file on .qcow2 format like standard setting.

Is possible, i need to change qemu.conf or other file?

I usually start off with building a qcow blank disk and then use it. One could use convert tools also to try to change it from one form or the other. In some cases a pre-allocated drive is better. Sometimes the grow process isn't in time with installers or loaders or such.

.qcow2 or .img doesn't matter, it's just the suffix, not the actual file format.

Originally Posted by dyasny .qcow2 or .img doesn't matter, it's just the suffix, not the actual file format.

Many thanks, now is all clear

KVM was built from Qemu. It should still have the qemu-img program available to convert the format... AND add compression if you desire (-c opt)

I use qemu not KVM but this should work for you.

qemu-img convert -c -O qcow2 jinix.img jinix.qcow