I never use qemu-img but just FYI my notes on how to resize raw image. To resize with 'raw' format.
1. To create image file in 'raw' format. guest# dd if=/dev/zero of=test.raw bs=1M count=64 oflag=direct 2. To boot VM with QEMU. host# qemu-system-x86_64 -m 4000M -enable-kvm -smp 4 -vnc :5 \ -net nic -net user,hostfwd=tcp::5025-:22 \ -device virtio-blk-pci,drive=drive0,id=virtblk0,num-queues=16 \ -drive file=ol7.qcow2,if=none,id=drive0 \ -device virtio-blk-pci,drive=drive1,id=virtblk1,num-queues=16 \ -drive file=test.raw,if=none,id=drive1 \ -monitor stdio -cpu host QEMU 4.2.0 monitor - type 'help' for more information (qemu) 3. To view disk size within VM. guest# cat /sys/block/vdb/size 131072 4 (optional). To extend the host image file from 64M to 128M. This step is optional as 'block_resize' in QEMU shell would be able to do that. host# dd if=/dev/zero of=test.raw bs=1M count=64 oflag=append conv=notrunc 5. To extend the host image file from 64M to 128M and propagate the change to guest via QEMU. (qemu) block_resize drive1 128M 6. Now the new disk size is available within VM. guest# cat /sys/block/vdb/size 262144 [ 124.446907] virtio_blk virtio1: [vdb] new size: 262144 512-byte logical blocks (134 MB/128 MiB) [ 124.448132] vdb: detected capacity change from 67108864 to 134217728 Dongli Zhang On 10/19/21 10:08 AM, Lentes, Bernd wrote: > Hi ML, > > is it possible to extend the disk (raw format) of a running guest with > qemu-img ? > > Thanks. > > > Bernd >
