HP XP Racks - Manual (Page 482)

Changing a Virtual I/O Server's Method of Recognizing
Virtual SCSI Disks
In HDLM version 5.8.1 or earlier, either PVID or unique_id can be selected
as the method used by a virtual I/O server for recognizing virtual SCSI disks.
In HDLM version 5.9 or later, only unique_id can be used because of the
MPIO specification. Also, the -u and the -e parameters of the dlmodmset
utility for setting the HDLM execution environment ODM are no longer
provided because they are also not necessary.
B-6
Differences Between HDLM Version 5.9 or Later and Version 5.8.1 or Earlier
Hitachi Dynamic Link Manager (for AIX) User Guide