Topics: AIX, System Admin

Switching between 32bit and 64bit

Before switching to 64bit mode, make sure the hardware supports it.

To verify what is running and what the hardware can support, run the following as root:

# echo "Hardware:\t`bootinfo -y` bits capable"
Hardware: 64 bits capable
# echo "Running:\t`bootinfo -K` bits mode"
Running: 32 bits mode
# ls -l /unix /usr/lib/boot/unix
lrwxrwxrwx 1 root system 21 Aug 15 2006 /unix -> /usr/lib/boot/unix_mp
lrwxrwxrwx 1 root system 21 Aug 15 2006 /usr/lib/boot/unix -> /usr/lib/boot/unix_mp
To switch from 32-bit mode to 64-bit mode run the following commands, in the given order:
# ln -sf /usr/lib/boot/unix_64 /unix
# ln -sf /usr/lib/boot/unix_64 /usr/lib/boot/unix
# bosboot -ad /dev/ipldevice
# shutdown -Fr
To switch from 64-bit mode to 32-bit mode run the following commands, in the given order:
# ln -sf /usr/lib/boot/unix_mp /unix
# ln -sf /usr/lib/boot/unix_mp /usr/lib/boot/unix
# bosboot -ad /dev/ipldevice
# shutdown -Fr




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