Configuration interface for IBM System Storage DS5000 and IBM DS4000 systems

The access LUN, also known as the Universal Transport Mechanism (UTM) LUN, is the configuration interface for IBM System Storage DS5000 and IBM DS4000 systems.

The access LUN might not be in a partition that contains the SAN Volume Controller ports because it is not required by the SAN Volume Controller cluster. The UTM LUN is a special LUN that allows IBM System Storage DS5000 and IBM DS4000 systems to be configured through suitable software over the fibre-channel connection. Because the SAN Volume Controller does not require the UTM LUN, it does not generate errors either way. IBM System Storage DS5000 and IBM DS4000 systems must not have the Access UTM LUN that is presented as LUN 0 (zero).

It is possible to use in-band (over fibre channel) and out-of-band (over Ethernet) to allow the configuration software to communicate with more than one IBM System Storage DS5000 or IBM DS4000 system. If using in-band configuration, the Access UTM LUN must be configured in a partition that does not include any logical units that are accessed by the SAN Volume Controller cluster.