July 22, 2003

Have You Had Tape Problems on the South System?

Recently, some South tape users have experienced problems when reading or writing to tapes. This problem exhibits itself during forward spacing of a tape—for example, reading a data set other than the first data set on the tape, skipping to the end of a data set to modify it or copying multiple data sets to a tape. Any of these examples can cause the system to lose its positioning and result in a permanent I/O error. This does not result in any loss of data but it is an inconvenience.

Unfortunately, because the South system has an older version of the operating system there is no fix available to correct this problem. Because the problem is sporadic—that is, it does not happen all of the time—the circumvention is to rerun the job and hope it doesn't recur. The permanent solution is to move your tape to Titan and process it there. This problem does not occur on Titan because the fix has been installed to eliminate it.

By coding RETAIN on the VOLUME parameter in your JCL you may reduce the chance of running into this problem when you are writing multiple data sets to the same tape within the same job. There is nothing you can do, however, to prevent the problem if you are modifying a data set or adding an additional data set to a tape that already has data sets on it. The best solution of course is to move to Titan.

For more information on coding RETAIN, see the OS/390 Batch and Utilities manual or call TASC at (301) 594-6248 for assistance.