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Replace Coupling Facility Structure Control Files

To replace a coupling facility structure control file, you deallocate that file using the DEALLOCATE command, then allocate a new file using the ALLOCATE command. You must issue these commands on all systems in the MIMplex.

For example, assume you want to remove a coupling facility list structure named MIMGR#TABLE02, with a control file ID of 02, from the use of CA MIM because you want to replace it with a new structure in a different coupling facility.

To replace the coupling facility structure control files in this example

1. Deallocate the control file by issuing the following command on all members in the MIMplex:

   DEALLOCATE XESFILEID=02
   

2. Define a new structure for CA MIM to use by updating the Coupling Facility Resource Management (CFRM) couple data set with a new policy and activate that policy.

   Note: For detailed information on the process, see the IBM publication Setting Up a Sysplex. You may want to see member ALLOCSTR in the CAI.CBTDJCL data set for sample JCL that can be used to update the CFRM policy.

3. Make the new coupling facility structure control file available to the CA MIM address space by allocating it to all members in the MIMplex. Assuming that the new structure name is MIMGR#TABLE03 and the file ID to be assigned to the control file is 03, issue the following command on all members of the MIMplex:

   ALLOCATE XESFILEID=03 STRNAME=MIMGR#TABLE03
   

You must specify both the file ID and the structure name of the new control file on the ALLOCATE command on all systems in the MIMplex. The ALLOCATE command formats the control file automatically, so you do not need to restart CA MIM.

Note: To replace a coupling facility structure control file that is currently the active control file, first you need to migrate to a new control file and then deallocate the abandoned coupling facility structure control file from all members of the MIMplex. Next, issue the SETXCF FORCE,STRUCTURE command to delete the XES structure, as the DEALLOCATE XESFILED command does not automatically do so. Once this is complete, the replacement XES structure can be defined in the new CFRM policy and activated.

More information:

How You Migrate to a New Control File