Active CICS Resource Types Managed in a PAC

Currently only a limited number of the CICS resource types can be managed in a PAC. Each of these resources might need specific processing in the PAC. For example, to open and close an FCT, or to copy an executable across the PAC. This topic describe the specific requirements for each resource type.

The following CICS resources are stored in the PSOR when configured and operating:

DCT
Although the DCT resources themselves are stored in the PSOR, the actual queue must be one of the following DCT types in order for it to be stored in a SOR by a SOR Model:
  • Non-recoverable
  • Intra-partition - which includes triggers
  • Indirect - model prefixes work only on the target DCT
Note: Recoverable, internal reader, and extra-partition types cannot be stored in a SOR.

When viewing information about TD queues in ESMAC, the following apply:

  • Information regarding SOR stored queues, such as number of items and depth, can be viewed by any enterprise server instance.
  • Information regarding queues stored on disk is only available to the local enterprise server instance.
ENQMODEL
An ENQMODEL is used to elect named resources for which ENQ/DEQ commands use a SYSTEMs wide scope (SYSTEMs vs SYSTEM).
FCT
The VSAM file referred to by the resource of this type can be stored in an RDBMS. See the MFDBFH configuration for requirements. Whether or not in MFDBFH, issuing a file close command in any enterprise server instance results in the file being closed by all instances in the PAC.
PCT
Active PCTs in a PAC will have two different count values:
  • A count of the number of times the transaction has been executed across the PAC.
  • A local count for each enterprise server instance of the number of executions in that instance.
PPT
Each enterprise server instance will load user applications from the location specified in its configured transaction path.

If you need to modify a program while a PAC is active, you need to uploaded the new binary file to the PSOR and then issue a New Copy command.

For example, the process to install a new version of the program myprog.dll is as follows:

  1. Load the new version of myprog.dll into the PSOR with the following command:
    caspac -aLoad="c:\new files\myprog.dll" -sredis,127.0.0.1:6379
  2. Issue the New Copy command via one of the following methods:
    • Using the CICS castran command:
      castran –rinstanceName  -nmyprog
    • Using the CICS CPMT transaction:
      CPMT NE MYPROG
    • Using an EXEC CICS SET PROGRAM command:
      EXEC CICS SET PROGRAM(MYPROG) NEWCOPY
Note:
  • Enterprise server instances will pick up all binaries that have been loaded into the PSOR at start time. If there are a large number of binaries in the PSOR it might take some time to acquire them all. This might result in programs not being immediately available at start up.
  • Binaries can get out of synchronization between enterprise server instances if a new instance joins the PAC after programs have been loaded into the PSOR and before a new copy command is issued. In this case, the new enterprise server instance will use the newer binary version. To synchronize the enterprise server instances in the PAC, issue a new copy command.
RNL
Both JCL and CICS use the RNLs list to determine which resource to ENQ/DEQ require SYSTEMS or SYSTEM scope:
  • JCL ENQ scope is determined by the RNLs definitions only.
  • CICS ENQ scope is derived from ENQMODELs. If scope is set in the ENQMODEL and NQRNL=YES is set in the SIT then the RNL LIST is checked.
TSMODEL
This is used to determine generic properties to apply to a set of TS queues.
TST
Only non-recoverable queues can be stored in a SOR.