Description: z/OS® supports up to four subchannel sets on IBM z13™ servers. This helps relieve subchannel constraints and can allow you to define larger I/O configurations that support multi-target Metro Mirror (PPRC), along with large numbers of PPRC secondaries and Parallel Access Volume (PAV) aliases. As with the prior support for up to three subchannel sets, you can define base devices, aliases, and secondaries in the first subchannel set (subchannel set zero), and define only aliases and secondaries in subchannel sets one, two, and three. All four subchannel sets support FICON® and zHPF protocols.
This support is available on z/OS V2R1 with the PTF for APAR OA43495.
When change was introduced: z/OS V2R1.
Reference information: z/OS MVS System Messages, Vol 9 (IGF-IWM)
