For experiment sake, I decided to duplicate my newly created RHEL session using ZFS. My Fedora and RHEL virtual instances each live on their own zvol. As you can see below, each VM has a zvol named disk0:
# zfs list -r local NAME USED AVAIL REFER MOUNTPOINT local 196G 717G 31K /local local/shared 196G 717G 172G /shared local/shared/Virtual 24.2G 717G 33K /shared/Virtual local/shared/Virtual/ISO 3.56G 717G 3.56G /shared/Virtual/ISO local/shared/Virtual/KVM 20.6G 717G 36K /shared/Virtual/KVM local/shared/Virtual/KVM/fedora 10.3G 717G 31K /shared/Virtual/KVM/fedora local/shared/Virtual/KVM/fedora/disk0 10.3G 724G 2.94G - local/shared/Virtual/KVM/rhel 10.3G 717G 31K /shared/Virtual/KVM/rhel local/shared/Virtual/KVM/rhel/disk0 10.3G 724G 2.89G -
To duplicate the RHEL virtual machine, I first created a snapshot of the volume while the RHEL VM was booted.
# zfs snapshot local/shared/Virtual/KVM/rhel/disk0@booted
I then cloned the RHEL VM to a new zvol:
# zfs clone -p local/shared/Virtual/KVM/rhel/disk0@booted local/shared/Virtual/KVM/rhel2/disk0
With the new cloned zvol, rhel2, the local zpool now looks like this:
# zfs list -r local NAME USED AVAIL REFER MOUNTPOINT local 199G 714G 31K /local local/shared 199G 714G 172G /shared local/shared/Virtual 27.1G 714G 33K /shared/Virtual local/shared/Virtual/ISO 3.56G 714G 3.56G /shared/Virtual/ISO local/shared/Virtual/KVM 23.5G 714G 39K /shared/Virtual/KVM local/shared/Virtual/KVM/fedora 10.3G 714G 31K /shared/Virtual/KVM/fedora local/shared/Virtual/KVM/fedora/disk0 10.3G 721G 3.04G - local/shared/Virtual/KVM/rhel 13.2G 714G 31K /shared/Virtual/KVM/rhel local/shared/Virtual/KVM/rhel/disk0 13.2G 724G 2.89G - local/shared/Virtual/KVM/rhel2 30.1M 714G 31K /shared/Virtual/KVM/rhel2 local/shared/Virtual/KVM/rhel2/disk0 30.0M 714G 2.89G -
I modified my kvm start script with a new MAC address and vnic and booted the new virtual machine.
I created and booted a completely new RHEL VM instance in literally less than a minute!