Why are SAN disks not available for AIX recovery when booting from network boot images?

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I have a system with SAN disks, and I’ve created a Storix network boot image from that system. If I boot that system from the network boot image into system maintenance, none of the SAN disks show up as available.

NOTE: This system uses MPIO instead of SDD to handle the multiple paths it has to each SAN disk. The default PCM that AIX uses isn’t so great (no load balancing, no automatic path recovery, etc), so we use the SDDPCM instead. The filesets we install are:

devices.sddpcm.53.rte
devices.fcp.disk.ibm.mpio.rte

It is only after installing these filesets that the network boot fails. If we uninstall the filesets, the network boot succeeds.

ANSWER

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We have found that IBM does not include the SDDPCM drivers on any boot media except when booting from disk. Creation of a bootable “mksysb” tape will suffer the same problem.

Storix creates boot media using the standard proto extension files that are installed with each driver. From the list of files in the SDDPCM filesets, it indicates that the proto extensions are put on the boot media only for bootable disks. When we create boot images, we include both the proto extensions for network boot images as well as for tape boot images (since we do not remote mount /usr when booting over the network as would NIM). Neither includes the SDDPCM files.

To resolve the problem, you can just make a copy of the file:
/usr/lib/boot/protoext/disk.proto.ext.fcp.disk.sddpcm.rte
and save it as:
/usr/lib/boot/protoext/tape.proto.ext.fcp.disk.sddpcm.rte

This will not only add the drivers contained in the file to the Storix network and tape boot images, but also a mksysb tape (although I can’t imagine why you would ever need one of those).