IBM High Availability Cluster Multiprocessing
IBM PowerHA SystemMirror (formerly IBM PowerHA and HACMP) is IBM's solution for high-availability clusters on the AIX Unix and Linux for IBM System p platforms and stands for High Availability Cluster Multiprocessing. IBM's HACMP product was first shipped in 1991 and is now in its 20th release - PowerHA SystemMirror for AIX 7.1.
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