Switching Between 32-bit and 64-bit Kernel in Solaris

This is extremely useful if you're testing/certifying your product against different architectures on Solaris OS. Typically you need to see if your software installs and works properly in both 32 and 64 bit modes of operation.

By default Solaris boots into 64 bit mode provided the underlying hardware supports it. If you need to boot in different modes, here's the command you need to issue from shell:

Solaris x86, 32 bit:

eeprom boot-file="kernel/unix"

Solaris x86, 64 bit:

eeprom boot-file="kernel/amd64/unix"

Solaris SPARC, 32 bit:

eeprom boot-file=""

Solaris SPARC, 64 bit:

eeprom boot-file="kernel/sparcv9/unix"

After you've issued one of the above commands, you'll need to simply reboot the system.

To check the current architecture of your Solaris OS here's the command:

root@was6test # isainfo -kv
64-bit sparcv9 kernel modules