working with kvm images

How to enlarge a kvm image

1. Stop the kvm maschine.

2. Convert the kvm image to raw format if necessary.

   qemu-img convert -O raw original.img raw.img

3. Make a backup copy of the image.

4. Enlarge the raw image.

   dd if=/dev/zero of=raw.img bs=1 count=0 seek=[size in]GB

5. Attach the enlarged image to a loop device.

   losetup /dev/loop0 raw.img

6. Use

   fdisk /dev/loop0

   to create a new partition or enlarge an existing one to accomodate the additional disk capacity.

7. Boot the machine using the new image.

8. Log in to the machine and start up lvm. Either add the new partition as a new physical volume (pvcreate) and add it to a volume group (vgextend) or in case an existing partition was enlarges use

   lvm> pvresize /dev/vda2

   and add the newly available space to logical volumes

   lvm> lvresize -L +511.02G /dev/philipp/home

9. Enlarge the filesystem (ext2/3).

   resize2fs /dev/philipp/home