Actions to avoid when you back up data

When backing up data, avoid certain actions to reduce problems that occur during data recovery.

Do not discard archive logs that might be needed

The RECOVER utility might need an archive log to recover from an inconsistent data problem. If discarded, the problem must be resolved manually without using the RECOVER utility.

Do not make an image copy of a table space or index space that contains inconsistent data

If the COPY utility is used to make an image copy of a table space or index space that contains inconsistent data, the RECOVER utility cannot recover a problem that involves that space (unless an older image copy is available that was taken before the problem occurred). Run DSN1COPY with the CHECK option to determine whether intra-page data inconsistency problems exist on table or index spaces before you make image copies of them. If a COPY of a catalog or directory table space is taken, run DSN1COPY CHECK (before image copies are taken) to verify the integrity of Db2 catalog and directory table spaces.

Do not use the -TERM UTILITY command on utility jobs you want to restart

If an error occurs while a utility is being run, the data on which the utility was operating remains at a commit point. If the utility stops while it has exclusive access to data, other applications cannot access that data. In this case, you can issue the -TERM UTILITY command to terminate the utility and make the data available to other applications. However, use the -TERM UTILITY command only if the utility job cannot be restarted or does not need to be restarted.

Issuing the -TERM UTILITY command can cause two different situations:

• If the utility is active, it terminates at its next commit point.
• If the utility is stopped, it terminates immediately.

By using the -TERM UTILITY command to terminate the REORG or LOAD utilities, or COPY utility for incremental image copies, the objects on which the utility was operating are left in an indeterminate state. Often, the same utility job cannot be rerun. The specific considerations vary for each utility, depending on the phase in process when you issue the command.