After the 64-bit Solaris release is installed on an UltraSPARC system, the 64-bit kernel will be booted automatically unless any of the following conditions are true:
A FLASH PROM upgrade may be required on an UltraSPARC system before it can successfully boot the 64-bit kernel. Refer to your hardware manufacturer's documentation to determine whether your UltraSPARC system requires a firmware upgrade.
The Open Boot PROM boot-file parameter is set to kernel/unix. If booting the 64-bit kernel fails and this parameter is set, unset it, and reboot the system.
On some UltraSPARC systems, the 64-bit Solaris kernel is not booted by default, even when the system is completely installed with all the 64-bit Solaris components and the correct firmware is installed. Without booting the 64-bit Solaris kernel, 64-bit applications are unable to run.
To find out more about this issue, and how to enable booting the 64-bit Solaris kernel by default, see boot(1m) and Solaris 7 (SPARC Platform Edition) Release Notes.
You can always discover which Solaris kernel the system is currently running by using the isainfo -kv command.
$ isainfo -kv 64-bit sparcv9 kernel modules |
This output means the system is running the 64-bit Solaris kernel.
You cannot boot the 64-bit Solaris operating environment on a 32-bit Solaris system.