If applicable, you can specify, for each structure in the CFRM policy, a value that MVS™ will use to determine whether to initiate a user-managed rebuild if connectivity is lost to a coupling facility containing that structure. Loss of connectivity can occur because of a failure of a coupling facility attachment or because of certain types of failures of the coupling facility itself.

The appropriate action for MVS to take depends on the scope of the failure and the nature of the sysplex. For example, in a configuration made up of large systems, it might be appropriate to rebuild the structure in another coupling facility so that all of the systems can continue accessing the structure. On the other hand, in a configuration of many small systems, it might be better to simply let one or more of the systems discontinue accessing the structure while the other systems continue their work.

To allow MVS to initiate a user-managed rebuild:

1. Have a structure for which all active connections support user-managed rebuild.
2. Specify a REBUILDPERCENT value in your CFRM policy for each structure that MVS is to evaluate for rebuild, or allow it to default to 1.
3. Optionally, have in place an active SFM policy that supports the use of system weight values for performing recovery actions in the event of loss of connectivity between systems.