boot net -s

boot cdrom -s, if it ask username: root/solaris or root/password.

on x86, you need edit grub and append -s on kernel line.

after login. mount /dev/dsk/cxtxdxsx /a

if you use zfs for /, then zfs import

zfs list

zfs set mountpoint=/a rpool/ROOT/solaris

zfs mount -f rpool/ROOT/solaris

then edit /etc/shadow

remove the password section, let it looks likes.

root::15356::::::

don’t forget to reset the mountpoint back

zfs set mountpoint=/ rpool/ROOT/solaris

reboot.