PPRCSUM

PPRCSUM (Peer-to-Peer Remote Copy Suspend Summary Notification) is a function that enables PPRC Suspend notifications by using summary notifications per CU instead of per individual device. This function can reduce the number of host notifications that occur when PPRC devices (especially many devices in 5 seconds) transition to the Suspend status. The message traffic related to PPRC Suspend and GDPS Freeze is significantly reduced.

This PPRCSUM function is available for a TrueCopy for Mainframe pair. When the DKCMAIN microcode version is A0-05-41-XX/XX or later, the PPRCSUM function is supported.

Messages displayed on the z/OS console:

• The PPRCSUM function is disabled:

  Each time a PPRC pair device is suspended, the IEA494I MVS system message is output to the z/OS console.

• The PPRCSUM function is enabled:

  When a PPRC pair device is suspended, the IEA075I MVS system message is output on the z/OS console. IEA075I contains information about all devices that have transitioned to the Suspend status in the target CU.

Restrictions that apply when the PPRCSUM function is enabled:

• Even when PPRCSUM is enabled, the IEA494I message might be output on some DEVs due to the effects of host I/O operations. Therefore, IEA494I and IEA075I might be displayed together.
• The number of TOTALs displayed in the IEA075I message might not be the same as the implementation DEV.
• If the SUSPEND instruction is performed from Business Continuity Manager to a PPRC pair, the IEA075I message might be output multiple times in the target CU.

The following table shows the z/OS system configuration item required when using PPRCSUM.