If you want to create a backup of an existing boot environment, for example, prior to modifying the original boot environment, you can use the beadm command to create and mount a new boot environment that is a clone of your active boot environment. This clone is listed as an alternate boot environment in the GRUB menu for x86 systems or in the boot menu for SPARC systems.
When you clone a boot environment by using the beadm create command, all supported zones in that boot environment are copied into the new boot environment.