By default, TSM reduces the number of distinct media volumes used to store backups. This means that it is possible to have data from two ARCMAIN backup jobs stored on the same physical volume. Any attempt to restore data from both backups in parallel causes the second job to hang while it waits for the tape volume to be read by the first job.
To minimize or prevent the storage of two ARCMAIN backups jobs on a single physical volume, do any of the following:
- Use the ARCMAIN options ALL and EXCLUDE on the ARCHIVE statement to collect many smaller database and table objects into a single Teradata backup job.
- Use the CATALOG option to selectively restore such objects with a minimal amount of tape scanning.
- Create different TSM management classes and storage pools.