Starting with the Solaris 10 10/08 release, the findroot command replaces the root command that was previously used by GRUB. The findroot command provides enhanced capabilities for discovering a targeted disk, regardless of the boot device. The findroot command also supports booting from a ZFS root file system.
The following is a description of the device naming convention that is used by the findroot command for various GRUB implementations:
Oracle Solaris Live Upgrade:
The x variable is the name of the boot environment.
Standard system upgrades and new installations for systems with ZFS support:
The p variable is the name of the root pool.
Standard system upgrades and new installations for systems with UFS support:
The N variable is an integer number that starts at 0.