Qemu-img resize

• Extend LVM on qcow2 images

qemu-img resize image_name.qcow2 +3G
image resized.

Verify: 

qemu-img info image_name.qcow2
image: image_name.qcow2
file format: qcow2
virtual size: 500G (536870912000 bytes)
disk size: 246G
cluster_size: 65536 
Format specific information:
   compat: 1.1
   lazy refcounts: true
   refcount bits: 16
   corrupt: false

Shrink

Your new image cannot be bootable. Make sure you understand implications.

qemu-img resize YOUR_VM_MACHINE_NAME.img -10G
qemu-img: warning: Shrinking an image will delete all data beyond the shrunken image's end. Before performing such an operation, make sure there is no important data there.
qemu-img: Use the --shrink option to perform a shrink operation

qemu-img resize --shrink YOUR_VM_MACHINE_NAME.img -10G
Image resized.

Process:

• qemu-img resize -> virt-resize -> lvextend --resizefs

Related commands

• virt-resize
• virt-filesystems
• virsh blockresize
• virt-sparsify

Activities

• Read https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/virtualization_deployment_and_administration_guide/sect-using_qemu_img-re_sizing_the_disk_image

See also

• qemu-img: qemu-img info, qemu-img check, qemu-img resize, qemu-img create, qcow2, qemu-img rebase, qemu-img convert, qemu-img commit, qemu-img ammend