Removing virsh VMs and associated storage contents

 

To delete a VM and its corresponding storage: (Use with caution you are deleting all the associated storage)

# virsh undefine --domain {VM_NAME_HERE} --remove-all-storage
 

 To delete the snapshots too:

 # virsh undefine --domain {VM_NAME_HERE} --delete-snapshots --remove-all-storage

 

 Another safer approach is

# virsh list --all# virsh dumpxml  {VM_NAME_HERE} // get the corresponding image.


# virsh undefine --domain {VM_NAME_HERE}

# rm -rf  /path/to/image

 

I faced a error like this:

error: Refusing to undefine while domain managed save image exists

First run this command:

sudo virsh managedsave-remove  --domain <domain name> 

Next:
# virsh undefine --domain {VM_NAME_HERE} --remove-all-storage

If you face error saying "cannot define domain with nvram" use --nvram with above command.

# virsh undefine --nvram --domain {VM_NAME_HERE} --remove-all-storage


source: https://www.cyberciti.biz/faq/howto-linux-delete-a-running-vm-guest-on-kvm/