OpenSolaris tips
(Direct document link)
Reboot to a specific boot environment:
# bootadm list-menu
the location for the active GRUB menu is: /rpool/boot/grub/menu.lst
default 0
timeout 10
0 zfsbe1
1 zfsbe1 Solaris xVM
2 zfsbe1 failsafe
3 zfsbe2
4 zfsbe2 Solaris xVM
5 zfsbe2 failsafe
# reboot [...]