A coupling facility runs as a special type of logical partition (LPAR) on certain System z and zEnterprise servers. See PR/SM Planning Guide for a list of all processors that support a coupling facility.

The coupling facility is defined through PR/SM™ panels. Once you have defined an LPAR to be a coupling facility logical partition, only the coupling facility control code can run in that partition. When you activate the coupling facility LPAR, the system automatically loads the coupling facility control code from the processor controller or the support element of the processor.

In the same manner, once you deactivate the coupling facility LPAR (for example, by doing a power-on-reset of the processor), the system does not preserve all coupling facility control code and any associated user data that might reside in the coupling facility.