Booting Solaris Systems to Either the 64-Bit Kernel or the 32-Bit Kernel

A common questions which I came across huge number of times while exploring the OpenSolaris forum - How do I configure the system to boot a 32-bit kernel or 64 bit kernel?.

This lead me to include it on my blog so as to help my friends with 32 bit and 64 bit availability of Solaris 10.
Here is the way to do that:

Booting into 32 bit:

You searched for Solaris 10 and just got to see a single ISO. No issues.

Log in as root and use the eeprom command to set the boot-file parameter to the 32-bit kernel:

# /usr/sbin/eeprom boot-file="kernel/unix"

The next time the system is rebooted, the 32-bit kernel will load.

To confirm what kernel your system is running now:

Run the following command:

$ /usr/bin/isainfo -kv
64-bit sparcv9 kernel modules

The 64-bit sparcv9 output indicates the system is running the 64-bit Solaris kernel.
Else, it is running 32 bit.

Hope this quick guide makes someone's day.