Defining APPC/MVS LUs as Syncpoint Capable

An installation defines the characteristics and resources for APPC/MVS LUs through APPL definition statements in SYS1.VTAMLST, and LUADD statements in APPCPMxx parmlib members.

To define new, or alter existing, LUs to make them syncpoint capable, complete the steps in the following checklist:

Make sure that each LU's APPL definition statement contains the SYNCLVL parameter with a value of SYNCPT. This parameter value defines the LU as capable of accepting conversations with any of the following synchronization levels: syncpt, confirm, or none.
Make sure that each LU's APPL definition statement contains the ATNLOSS parameter with a value of ALL.
Check LUADD statements to make sure the values match what you want for specific syncpoint-capable LUs. If you want to restrict the LU to process protected conversations only, for example, check the TPDATA parameter to ensure that the TP profile data set is one containing only TPs that allocate protected conversations.

If you need additional information about VTAM® resource definitions, refer to:

z/OS Communications Server: SNA Network Implementation Guide for detailed guidance about APPLs, and
z/OS Communications Server: SNA Resource Definition Reference for complete descriptions of APPL statement syntax and parameters.

For additional details about LUADD statements, refer to Adding a Local LU — LUADD Statement, Modifying a Local LU — LUADD Statement, and z/OS MVS Initialization and Tuning Reference.

After completing the checklist, the LUs and, by extension, the schedulers and APPC/MVS servers associated with them, are capable of handling protected conversations. Changes to alternate transaction schedulers and APPC/MVS servers are not necessary; however:

Alternate transaction schedulers may use the new Identify service to have APPC/MVS request a privately managed context for that scheduler. For details, refer to z/OS MVS System Messages, Vol 3 (ASB-BPX).
Depending on the model, APPC/MVS servers might require changes to handle protected conversations. For details, refer to z/OS MVS Programming: Writing Servers for APPC/MVS.