T 2.10 Data media are not available when required

Correct use of data media is of particular importance to many business processes and IT procedures. Even minor errors such as poor labelling, unsuitable storage sites, and missing entry or removal confirmations in the data media archive can prevent a data medium from being located in the required time. The resultant delays can cause significant damage.

Examples:

• While writing a business report in a company, it was discovered that the signed inspection report from the external auditor could not be found in the files. Since it was necessary to have the original copy of this document, the entire file system needed to be searched through. Even though the report was finally found, the business report could still not be completed by the planned deadline.
• Backup tapes are accidentally stored in an external data backup archive. If it becomes necessary to reconstruct the data, there will be significant delay because it is impossible to retrieve the tapes immediately.

• Backup tapes containing different data are accidentally labelled identically. The archive administrator inadvertently releases the most recent tape for deletion. As a result, only an outdated backup is available.
• Tape administration systems in the z/OS operating system use batch jobs to identify data backup tapes whose expiration dates have been reached so that they can be released for overwriting. If such a batch job crashes or is unable to start, then there may not be enough empty tapes (scratch tapes) for subsequent backups, and tape processing bottlenecks could arise.