To activate SMS, perform the following steps:

1. Define SMS to the operating system.

   Update the PARMLIB members on all the systems where SMS is intended to run. If you are sharing DASD between systems, you only need to activate the SMS configuration on one system; the COMMDS activates the other systems. If you want to prevent initial activation on other systems, the ACDS and COMMDS should reside on non-shared volumes.

2. Initialize the SMS address space.

Recommendation: To simplify recovery, leave empty one of the eight system or system group name slots for 8-name mode, and one of the 32 system or system group name (or a combination or both) slots for 32-name mode. If a problem occurs (such as a hardware failure), you might need to specify a system that was in the configuration as part of a system group. If there is an empty name slot, you can add the system name without disrupting the other systems in the SMS complex.

These are the steps for recovery:

1. Use the ISMF CDS Application (option 3) to add the system name to the SMS configuration.
2. Activate the configuration, either from ISMF or from the operator console.
3. Use the VARY SMS operator command to update the configuration.
4. When the problem is corrected, remove the system name from the configuration.
5. Reactivate the configuration.