DMB mismatch during database maintenance and operation

Initial database load

If a DMB mismatch is found during the initial load of the database, use the LICON utility to create an RDE by specifying the DBDLIB and the load library that contains the user exit routine that is used for the initial load, and redo the initial load of the database.

In certain circumstances, Integrity Checker automatically creates an RDE and does not verify the DMBs. For more information about how Integrity Checker maintains RDEs during initial database load, see RDE maintenance at initial database load.

Database reorganization

For a database reorganization that does not accompany a DBD change, DMB verifications run while the database is being unloaded and reloaded. If a DMB mismatch is found, it means that an incorrect DBDLIB, IMS directory, or a load library that contains incorrect user exit routine is used. To resolve the problem, see Addressing a DMB mismatch.

For a database reorganization that accompanies a DBD change, the first DMB verification is done while the database is being unloaded. For this DMB verification, Integrity Checker uses the DMB information before the DBD change. The second DMB verification is done while the database is being reloaded. For this DMB verification, Integrity Checker uses the DMB information after the DBD change. If a DMB mismatch is found, it indicates that either a new RDE was not created or an incorrect DBDLIB, IMS directory, or a load library that contains incorrect user exit routine is used. Ensure that a new RDE is created before database reload. For a DMB mismatch caused by other errors, see Addressing a DMB mismatch.

In certain circumstances, Integrity Checker automatically creates an RDE. For more information about how Integrity Checker maintains RDEs during database reorganization, see RDE maintenance at database reorganization.

Database recovery

When you recover the database to the state that is defined by the current DBD, Integrity Checker verifies the DMB by using the latest DMB information. If a DMB mismatch is found, it means that an incorrect DBDLIB, IMS directory, or a load library that contains incorrect user exit routine is used.

If a DMB mismatch is found during a recovery to a state before a DBD change (time stamp recovery), it means that the correct RDE is not restored or an incorrect DBDLIB, IMS directory, or a load library that contains incorrect user exit routine is used. Ensure that the correct RDE is restored before recovering the database.

In both cases, for a DMB mismatch caused by other errors, see Addressing a DMB mismatch.

In certain circumstances, Integrity Checker automatically restores the RDE. For more information about how Integrity Checker maintains RDEs during database recovery, see RDE maintenance at database recovery.

DBD change

If a DMB mismatch is found after a DBD change, ensure that an incorrect DBDLIB, IMS directory, incorrect RECON data sets, or a load library that contains incorrect user exit routine is not used. Also, ensure that the DBD change was done with appropriate procedures, and that the DBDLIB, IMS directory, the RECON data sets, or the user exit routine was regenerated to apply the change. If these steps are not done yet, perform the steps.

If a DMB mismatch is found after restoring a DBD change, ensure that an incorrect DBDLIB, incorrect IMS directory, incorrect RECON data sets, or a load library that contains incorrect user exit routine is not used. Also, ensure that the DBD was restored with appropriate procedures, and that the DBDLIB, the IMS directory, the RECON data sets, or the user exit routine was regenerated or restored to roll back the change. If these steps are not done yet, perform the steps.

In both cases, for a DMB mismatch caused by other errors, see Addressing a DMB mismatch.