Migration planning for Named Counter and Shared Temporary Storage servers

Start of changeNamed Counter servers and Shared Temporary Storage servers can be at different levels in different MVS™ images, even when connected to the same coupling facility structure. They still function correctly in these circumstances. Each MVS image only uses a single server for each coupling facility structure, so all accesses to the coupling facility structure from each MVS image execute server code that is at the same level.End of change

All of the CF-related servers including the named counter server can be closed down immediately using the server CANCEL command.

There is no difference between the temporary storage server and the named counter server relating to recovery, in that both servers store all of their data in the coupling facility structure, so it will be lost if the structure fails or the coupling facility is re-IPLed. There may be a distinction from the application point of view, in that the scratch pad information stored in the temporary storage structure may be less important to continuous operation than sequence numbers stored in named counters.

The Application Programming Guide contains a section on Named Counter Recovery considerations. In a production environment, it is important to have some separate means of recreating the named counters if the coupling facility structure is lost, for example by determining the latest used counters from data bases.

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