Reference Guide

ZCOM Message Handling
ZLU Definition
Chapter 226
Mapped ZLUs
All messages addressed to a particular ZLU will be redirected to the
alternate ZLU specified in the zmapr routine call if the original ZLU has
been mapped to a different ZLU. One use of mapped ZLUs is for
providing high availability systems. For example, if a hardware failure
was detected in one of the ACC Mux cards, the application could map all
of the ZLUs associated with the failed card to a spare unused card in the
system.