IBM RS/6000 - Manual (Page 87)

4.3.3 Boot Image Creation on PCI-Based RS/6000 Systems
To support boot image creation for PCI-based RS/6000 systems, several
commands involved within the boot support process were changed in AIX Version
4. The changes were limited to a minimum, and the main idea is to still use the
bosboot command to generate a boot image. Some options have been changed in
bosboot to support the new platforms (SMP and RSPC systems). In fact, most of
the changes are hidden to the user. The command bosboot -a will create a boot
image for the platform type of the system running the command.
Cross Boot Image
Creation of boot images for a different target platform is possible on servers
which have installed the required base proto and proto extension files and the
predefined database for the target platform.
When using the Network Installation Manager (NIM), all the devices' software
packages are installed, and NIM handles different boot images according to the
target platform type.
Figure 24 on page 64 shows the components and commands involved within the
process of creating the AIX Version 4 boot image.
Chapter 4. Boot Support and Firmware 63