SMP Backup and Restore Jobstreams

Of course, you can always just shut down Hercules and use either Windows or Linux utilities to make backup copies of the files containing the MVS DASD volumes.  But, depending upon the point to which you want to restore, it is sometimes simpler to have an MVS backup available to restore from.

If you will download the archive smpsnap.tgz [MD5: CEF057F7D61E0D6ACF198238E8A6EECC] from this site, it contains two jobstreams.  The first jobstream creates a backup tape of the SMP001 volume you have been creating during the SMP process.  The second jobstream will restore the volume from the backup tape.

Creating a Backup

The jobstream to create the backup tape, BACKSMP.JCL, is quite simple.  The single step uses the utility IEHDASDR to dump DASD volume SMP001 to an AWS tape.  

 You may prefer to edit the jobstream to change the volume serial number of the output tape, which is currently set to 000256.  You will need to initialize a "scratch" tape prior to running the jobstream.

To run the jobstream, first create a scratch tape; in a console window (Linux) or MS-DOS command prompt (Windows/??), type the command:

hetinit tape\smp001.het 000256

You may change the name of the AWS image and volume serial number as you desire.  You may also need to change the location of the AWS tape image file; I have assumed here that you have followed my suggested directory structure and are executing the command from the mvs\ directory.

Submit the jobstream:

devinit 012 jcl\backsmp.jcl eof

When a tape is requested on the MVS console, "mount" the tape on the drive at address 170:

devinit 170 tape\smp001.het

At the completion of the job, the return code from the single step should be 0000, and you have a backup from which you can recover to this point, with the distribution libraries ready to proceed into System Generation.  I burn a copy of this AWS image onto a CD-ROM for permanent storage.

Restoring from the Backup

Restoring the tape requires a bit more manual effort, but only if you have placed additional datasets onto the SMP001 DASD volume that were not there when the backup tape was created.  The reason for this is that the SMP datasets are catalogued in the catalog on the starter system (and later will also be recataloged on the MVS 3.8 system).  If you have not placed datasets of your own on the volume, then just restoring from the backup tape is all that is required to have a volume which matches the catalog.  If you have created your own datasets on the SMP001 volume, and cataloged them in the system catalog, you will need to remove the catalog entries either before or after you restore from the backup tape, since they will not be on the volume after the restore takes place.  The simplest solution is to not place any datasets onto SMP001 except for SMP datasets.

The jobstream for restoration of the backup, RESTSMP.JCL,  is a bit more complex, but not hard to understand.  The jobstream actually contains two jobs.  The first job varys the SMP001 volume offline, then uses ICKDSF to re-initialize it.  The final step of this job is to submit a second job to the internal reader.  The second job varys the volume back online and restores the contents of the backup tape.  It is necessary to have two jobs so that the vary commands are executed in the correct time sequence.

It may be necessary to edit the jobstream if your "hardware" configuration is different from mine.  I assume that the SMP001 DASD volume resides at hardware address 148.  If you have changed the backup tape dataset name or volume serial number, you will also have to ensure that those changes are reflected in the restore jobstream.

To submit the jobstream:

devinit 012 jcl\restsmp.jcl eof

When a tape is requested on the MVS console, "mount" the tape on the drive at address 170:

devinit 170 tape\smp001.het

The return codes of all steps of both jobs should be 0000.  

I hope that you have found my instructions useful.  If you have questions that I can answer to help expand upon my explanations and examples shown here, please don't hesitate to send them to me:

This page was last updated on April 22, 2008 .