Example 1: Recovering the MCDS from DASD

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

SETSYS CDSVERSIONBACKUP(BACKUPCOPIES(3) -
     BACKUPDEVICECATEGORY(DASD))

Now you let DFSMShsm execute to a point where 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 V0000008, V0000009, and V0000010.

As DFSMShsm processes the MCDS, an I/O error occurs, so a part of the MCDS is no longer usable. To recover the MCDS, you would:

1. Issue QUERY CDSVERSIONBACKUP to find out what was the latest backup version. DFSMShsm issues the following messages:

   ARC0375I

   CDSVERSIONBACKUP,

    

   MCDSBACKUPDSN=uid.MCDS.BACKUP,

    

   BCDSBACKUPDSN=uid.BCDS.BACKUP,

    

   OCDSBACKUPDSN=uid.OCDS.BACKUP,

    

   JRNLBACKUPDSN=uid.JRNL.BACKUP

    

    

   ARC0376I

   BACKUPCOPIES=3,

    

   BACKUPDEVICECATEGORY=DASD,

    

   LATESTFINALQUALIFIER=V0000010,

    

   DATAMOVER=HSM

   Recommendation: If the QUERY CDSVERSIONBACKUP command is not successful or if DFSMShsm is not active, issue the following IDCAMS LISTCAT command to determine the latest version: LISTCAT LEVEL(uid)
2. Issue a IDCAMS LISTCAT(uid) to determine if the backup copy is good. This determination is made by checking the low-level qualifier for a V or an X.
3. Stop DFSMShsm in all processing units.
4. See Requirements for using the enhanced CDS recovery function for information on using the enhanced CDS recovery function to recover the MCDS.
5. Restart DFSMShsm in the processing unit.
6. Verify that the control data sets are correct (see Determining if control data sets are accurate).
7. Fix any errors in the control data sets (see Repairing errors in the control data sets).
8. Because you are recovering the MCDS, issue a QUERY CDSVERSIONBACKUP command to ensure that the latest final qualifier is the same as that shown in step 1. If you do not have the output from query command in step 1, you can determine the final qualifier of the latest backup copy from your catalog using the LISTCAT LEVEL command, as shown in the following example:

   LISTCAT LEVEL(uid)

   If these qualifiers do not match, use the FIXCDS patch command to correct the field at offset X'B1' in the MHCR record to reflect the latest version in the catalog, as shown in the following example:

   FIXCDS S MHCR PATCH(X'B1' 0000010)

9. Issue the BACKVOL CDS command to ensure that all copies of the control data sets and the journal data set are current. During backup of the control data sets and the journal data set, DFSMShsm issues the following messages:

   ARC0740I

   CDS BACKUP STARTING AT 04:15:35 ON 95/05/24 ON SYSTEM 381A TO DASD IN PARALLEL MODE, DATAMOVER=HSM

    

    

   ARC0742I

   BACKUP FOR MCDS STARTING AT 04:15:55 ON 95/05/24, BACKUP COPY TECHNIQUE IS UNDEFINED

    

    

   ARC0743I

   MCDS SUCCESSFULLY BACKED UP TO uid.MCDS.BACKUP.V0000008, ON VOLUMES VOL001,VOL002, TIME=04:20:03, DATE=95/05/24

    

    

   ARC0742I

   BACKUP FOR BCDS STARTING AT 04:25:55 ON 95/05/24, BACKUP COPY TECHNIQUE IS UNDEFINED

    

    

   ARC0743I

   BCDS SUCCESSFULLY BACKED UP TO uid.BCDS.BACKUP.V0000008, ON VOLUMES VOL003,VOL004, TIME=04:30:13, DATE=95/05/24

    

    

   ARC0742I

   BACKUP FOR OCDS STARTING AT 04:35:55 ON 95/05/24, BACKUP COPY TECHNIQUE IS UNDEFINED

    

    

   ARC0743I

   OCDS SUCCESSFULLY BACKED UP TO uid.OCDS.BACKUP.V0000008, ON VOLUME VOL005, TIME=04:40:44, DATE=95/05/24

    

    

   ARC0750I

   BACKUP FOR JRNL STARTING AT 04:40:55 ON 95/05/24

    

    

   ARC0743I

   JRNL SUCCESSFULLY BACKED UP TO uid.JRNL.BACKUP.V0000008, ON VOLUME VOL006, TIME=04:45:26, DATE=95/05/24

    

    

   ARC0748I

   LAST SUCCESSFUL CDS BACKUP-SET QUALIFIER IS V0000011

    

    

   ARC0741I

   CDS BACKUP ENDING AT 04:45:35 ON 95/05/24, STATUS=SUCCESSFUL

   Note: Because you have specified three backup copies and you are backing up to DASD, DFSMShsm replaces the V0000008 version of the backup data sets with V0000011.
   If you issue the QUERY CDSVERSIONBACKUP command again, DFSMShsm issues the following messages:

   ARC0375I

   CDSVERSIONBACKUP,

    

   MCDSBACKUPDSN=uid.MCDS.BACKUP,

    

   BCDSBACKUPDSN=uid.BCDS.BACKUP,

    

   OCDSBACKUPDSN=uid.OCDS.BACKUP,

    

   JRNLBACKUPDSN=uid.JRNL.BACKUP

    

    

   ARC0376I

   BACKUPCOPIES=3,

    

   BACKUPDEVICECATEGORY=DASD,

    

   LATESTFINALQUALIFIER=V0000011,

    

   DATAMOVER=HSM

10. Restart DFSMShsm in the other processing units.