Specifying Extended PDSE Sharing in a Multiple-System Environment

In a multiple-system environment, the system programmer uses PDSESHARING(EXTENDED) to share PDSEs at the member level. A system programmer must specify PDSESHARING(EXTENDED) in the IGDSMSxx member in the SYS1.PARMLIB on each system in the sysplex. Every system that is sharing a PDSE must be a member of the sysplex and have the sysplex coupling facility (XCF) active.

To change the PDSE sharing option to extended, a system programmer must follow these steps for each z/OS system in the sysplex that is running with extended sharing:

Modify SYS1.PARMLIB member IGDSMSxx to specify PDSESHARING(EXTENDED) on each system.
Issue the SET SMS=xx command, identifying the SYS1.PARMLIB member that starts the migration to the EXTENDED protocol. If you have a common SMS member shared between all the systems of the sysplex, you can issue the system command RO *ALL,SET SMS=xx on any system to route the SET command to all the other systems in the sysplex.

This SET SMS command establishes each system's preference, and negotiation between the sysplex members takes place. When all members have agreed to extended sharing, the sysplex can switch to that level of sharing.

Note: No systems change to extended sharing until they have all issued the SET SMS=xx command. You may see the following message on each system:

IGW303I NORMAL PDSE SHARING FORCED, INCOMPATIBLE PROTOCOL FOUND

In this case, you may have to issue the SET SMS=xx a second time to trigger the switch from NORMAL to EXTENDED sharing. All the systems will issue message IGW306I when they migrate to EXTENDED sharing:

IGW306I MIGRATION TO EXTENDED PDSE SHARING COMPLETE