Example 2: Replacing a damaged journal

This example shows how you set up your environment, how to recover the journal, and some of the messages that are issued during the backup and recovery processing.

Set up your environment with the following SETSYS command:

SETSYS CDSVERSIONBACKUP(DATAMOVER(DSS) -
     BACKUPCOPIES(4) -
     MCDSBACKUPDSN(BHSM.MCDS.BACKUP) -
     BCDSBACKUPDSN(BHSM.BCDS.BACKUP) -
     OCDSBACKUPDSN(BHSM.OCDS.BACKUP) -
     JRNLBACKUPDSN(BHSM.JRNL.BACKUP) -
     BACKUPDEVICECATEGORY(DASD))

You preallocate the following backup data sets:

        BHSM.MCDS.BACKUP.D0000001
        BHSM.BCDS.BACKUP.D0000001
        BHSM.OCDS.BACKUP.D0000001
        BHSM.JRNL.BACKUP.D0000001

        BHSM.MCDS.BACKUP.D0000002
        BHSM.BCDS.BACKUP.D0000002
        BHSM.OCDS.BACKUP.D0000002
        BHSM.JRNL.BACKUP.D0000002

        BHSM.MCDS.BACKUP.D0000003
        BHSM.BCDS.BACKUP.D0000003
        BHSM.OCDS.BACKUP.D0000003
        BHSM.JRNL.BACKUP.D0000003

        BHSM.MCDS.BACKUP.D0000004
        BHSM.BCDS.BACKUP.D0000004
        BHSM.OCDS.BACKUP.D0000004
        BHSM.JRNL.BACKUP.D0000004

Assume DFSMShsm has successfully backed up the control data sets and the journal data set ten times. The backup data sets have the final qualifiers of D0000007, D0000008, D0000009, and D0000010.

As DFSMShsm processes the journal data set, an I/O error occurs. DFSMShsm disables the journal data set and issues the following message:

ARC0026A JOURNALING DISABLED DUE TO I/O ERROR.
MIGRATION, BACKUP, DUMP, AND RECYCLE HELD.

Issue a BACKVOL CDS command to back up the control data sets and the journal data set. DFSMShsm successfully backs up the control data sets and issues message ARC0743I for each backup. The message indicates that DFSMShsm made the backup to the backup data set whose final qualifier is D0000007 (oldest version).

When DFSMShsm tries to back up the journal, another I/O error occurs. Because DFSMShsm cannot successfully complete the journal data set backup function, it renames the journal backup data set to X0000011. Then DFSMShsm issues the following message:

   ARC0744E   JRNL COULD NOT BE BACKED UP,
                   RC=retcode, REASON=reascode
                   MIGRATION, BACKUP, DUMP, AND RECYCLE HELD.

In addition, DFSMShsm issues the following message to indicate the latest final backup data set qualifier (D0000011). DFSMShsm waits for the completion of the CDS backups and then nulls (empties) the journal data set if no CDS backup failures occur.

ARC0748I LAST SUCCESSFUL CDS BACKUP-SET QUALIFIER IS
D0000011

At this point, assume the following conditions exist:

The latest backup versions of the control data sets are backup data sets whose final qualifier is D0000011.
The latest good backup version for the journal data set is a backup data set whose final qualifier is D0000010.
The current control data sets are usable.

If you want to continue processing with the journal, you must stop DFSMShsm, delete and reallocate the journal data set to avoid getting another I/O error during processing of the data set. This process is described in Reasons for recovering the control data sets. A hardware problem could be causing the I/O error on the journal data set, so be sure you do not re-allocate the journal data set to where it was allocated before the I/O error occurred.

After you restart DFSMShsm, issue BACKVOL CDS to back up the control data sets and the new, empty journal data set. DFSMShsm backs up the control data sets and the journal data set to the backup data sets whose final qualifiers are D0000008. If DFSMShsm successfully backs up the control data sets and the journal data set, DFSMShsm renames the backup data sets with the final qualifier of D0000012 (or V0000012 if IDCAMS is the data mover).