Disaster Recovery Backups (MVS)

Backups for the MVS systems are of two flavors: Full Volume and Incremental. These are created using the FDR/ABR utilities from Innovation Data Processing, Inc.

Full Volume Backups

Full Volume backups are taken each weekend. All volumes are backed up with the exception of volumes that are contain temporary data sets only, plus the JES2 spool volume. The tapes are taken off-site on the following Monday. Full Volume backups are identified by the data set naming convention FDR.TAPE.XXXXXX where XXXXXX is the volume serial number for the disk volume that was backed up. Full volume backup tapes expire on a 21-day retention cycle.

Incremental Volume Backups

Incremental backups of select disk volumes are taken each night. These contain datasets that have been opened for output or update since the last time they were backed up. The tapes are taken off-site the following morning. Incremental backups are taken for volumes with volume serials PRODxx and TESTxx. VSAM data sets are not included in these backups. Recovery of individual VSAM datasets from a source other than the weekly volume backups will depend on application backups.

Database Backups

Certain database and application backups are also taken off site on a daily basis. Among these are backups of the ADABAS database management system (described more fully below) and VSAM files. VSAM file backups are done by individual applications rather than wholesale backups of all VSAM files.

CA-1 Tape Management Catalog

Another important item carried off site is a listing of the CA-1 tape management catalog. This will provide critical information concerning volume-serial numbers and data set names for the backup tapes.

Disaster Recovery Backups (ADABAS)

Backups for the ADABAS data bases are of two flavors: Full and Incremental. These are created using Software AG's Delta Save Facility. The Online Full backups and Online Delta backups are merged with the ADABAS Protection log to create Offline Full backups and Offline Delta backups, respectively. This simplifies the restoration process for the database.

Full data base backups are taken each Sunday or when desired. All data bases have full backups with the exception of the Maintenance data base that is used by the DBAs for installing and testing new software. There are two copies made. One stays on site; the other is taken off site. Full data base backups are identified by the data set naming convention shown below. The data sets are generation data sets. At least three generations of the Full backups are available at any point in time, all rotated between the off site storage locations.

Incremental backups are taken each morning except Sunday. These backups contains the RABNs that were updated and the files that were hit by update ADABAS Utilites since the last backup. There are two copies made. One stays on site, and the other is taken off site. Incremental backups are identified by the data set naming convention shown below. The data sets are generation data sets. At least two generations of the Incremental backups are available at any point in time, with off-site rotations to the Bell Engineering Building only.

Type  Location      Data Set Name (DSN)             RETPD
---- --------   -------------------                 -----
Full   Onsite   xxxx.ADABAS.FULL.OFFLINE.BACKUP1      60
Full   Offsite  xxxx.ADABAS.FULL.OFFLINE.BACKUP2      14
Delta  Onsite   xxxx.ADABAS.DELTA.OFFLINE.BACKUP1     14
Delta  Offsite  xxxx.ADABAS.DELTA.OFFLINE.BACKUP2      7

xxxx - is the data base (TEST, DEMO, PROD, SIS1, SIS2, or SIS3)

Another important item carried offsite is a report of the ADABAS Offsite tapes for Disaster recovery. This will provide critical information concerning volume serial numbers and data set names for the backup tapes. The CA-1 tape management catalog listing accompanies the tapes that go off-site.

Another important part is the protection log for going forward from the last backup to the time of the disaster. The protection log starts on disk, but it is dumped to tape when one of the the protection log data set becomes full or the operator or a batch job such as the backup job switches the protection log data sets.

Protection log tapes are identified by the data set naming convention xxxx.ADABAS.PROTECT.BKP1 and xxxx.ADABAS.PROTECT.BKP2 where xxxx designates the data base (TEST, DEMO, PROD, SIS1, SIS2, or SIS3). These tapes are kept onsite. BKP1 expires in 30 days while BKP2 expires in 7 days.

I have kept some additional data sets on the protection log tape for on-line recovery. These are from the past when we did not have Delta Save. The first one is a report created by ADARAI, and this is the second data set. The second one is a JCL created by ADARAI, and it is the third data set. These are of no use since we have installed Delta Save, but I am hoping in the future ADARAI and Delta Save will work together so that these outputs will be useful again.

The last data set on the tape is a tape listing from the TMC that is in data set order.

Disaster Recovery Backups (VM)

Backups for VM systems are taken each weekend. These backups are created with the VM Dump/Restore Utility (DDR). DDR creates an image backup of each VM volume is created. An important point to remember is that the DDR backups do not backup CP page or spool areas. These areas must be formatted for use by CP when restoring a volume before CP can use them. Three sets of tapes are used to hold the backups. These three sets are rotated to offsite storage. Each weekend the oldest set is overwritten.

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