Saving MSDBs for restart

At system checkpoint, a copy of all MSDBs is written alternately to one of the MSDB checkpoint data sets—MSDBCP1 or MSDBCP2.

During restart, the MSDBs are reloaded from the most recent copy on MSDBCP1 or MSDBCP2. During an emergency restart, the log is used to update the MSDB. During a normal restart, the operator can reload from MSDBINIT using the MSDBLOAD parameter on the restart command.

On a cold start (including /ERE CHKPT 0), MSDBs are loaded from the MSDBINIT data set.