FDR and FDRDSF overview

FDR

Program Fast Dump Restore (FDR) provides full-volume backups and restores, as well as full-volume DASD-to-DASD copies. FDRis described in detail in Working-with-FDR.

Full volume backups

FDRbackups operate on one DASD volume at a time, writing the full-volume backup to a tape or DASD data set. A separate backup data set is required for each DASD volume processed.

The FDRexecution JCL specifies the DASD volumes to backup, and the backup data set for each. The backup will contain an image of:

The label track (Cylinder 0 Track 0), including IPL text for IPLable volumes.
The VTOC tracks.
The VTOCIX (Indexed VTOC) tracks.
The VVDS tracks if one is present (VSAM clusters and SMS-managed data sets.
All tracks that are allocated to other data sets and VSAM clusters, determined by analyzing the Data Set Control Blocks (DSCBs) in the VTOC. Tracks that are not currently allocated to any data set are not backed up.
An edited version of information from the VTOC and VVDS is also stored at the beginning of the backup, serving as an index of the data actually in the backup, and providing information for allocation of output data sets during data set restores.

FDRcan optionally create two backup data sets concurrently, while reading the input DASD volume only once. FDRcan also optionally backup several DASD volumes concurrently, using internal sub tasking, as long as the backups are directed to separate tapes or DASD data sets.

Important

A common format is used for all backups in the

FDR

DASD Management System, including

FDR

, DSF, ABR, and SAR (see Data Set Backups); this means that

FDR

and FDRDSF can restore from tapes created by FDRABR, and vice versa. Actually, the

FDR

format has been modified several times since its initial release as support for new DASD devices was added and performance improvements were made. Although newer formats may not be able to be restored by older releases of

FDR

, the current

FDR

can always restore older backups.

Warning

FDR

format backups cannot be copied by standard copy utilities, such as IEBGENER.

FDR

includes a utility, FDRTCOPY, which is used to copy

FDR

backups.

Full volume restores

FDRrestores a physical image of a DASD from an FDRfull-volume backup file. The DASD volume receiving the restore must be the same device type (for example, 3390), but not necessarily the same size (number of cylinders) as the volume that was dumped. All the tracks in the backup data set are restored to their original locations (cylinder and head address). Every restored track looks exactly like it did when dumped; data sets are not reorganized, re blocked or changed in any other way.

The output DASD volume usually becomes an exact image of the original DASD including its volume serial, but you can optionally retain the volume serial of the output DASD, and can rename key data sets (such as the VTOCIX and ABR Model DSCB) during the restore.

If the restore results in a volume with a volume serial that duplicates another online volume (namely, when the original volume is still online), FDR places the output volume offline. You must relabel one or the other volume before the next IPL, so a reminder message is sent to the operator's console.

SMS-managed volumes are always renamed to the original volume serial number from the backup when restored.

DASD to DASD copying

FDRallows you to copy one DASD volume to another DASD volume of the same type. Essentially this does a backup and restore all in the same job, so all considerations for restore apply. No backup data set is required, but you can optionally create an FDRbackup during the copy operation.

Important

FDR

full-volume copies can be used to move DASD volumes from one hardware device to another, but it is disruptive, meaning that you must quiesce all activity and release all allocations to the volume during the move.

FDRPAS

, a separate product that has its own manual, allows you to do non-disruptive moves of volumes to new hardware, without quiescing any activity or interrupting normal use of the volume during the move. Contact BMC for more information on

FDRPAS

FDRDSF

Program FDRDSF (Data Set Functions (DSF)) performs backups and restores of selected data sets and VSAM clusters. It can also do data set restores from full-volume backup tapes produced by FDR, ABR, and SAR, as well as from data set backups produced by ABR. FDRDSF is described in detail in Working-with-FDRDSF.

Data set backups

FDRDSF backups are similar to FDRbackups, using the same format, but containing only the information and data tracks associated with the data sets selected by DSF control statements. You may select data sets by specific name, by prefix, or by sophisticated data set name masking. DSF backups operate on one DASD volume at a time, reading the VTOC of the volume, backing up the data sets you have selected and writing the backup to a tape or DASD data set; a separate backup data set is required for every DASD volume processed but that backup data set may contain backups of many original DASD data sets. The backup contains an image of:

All tracks that are allocated to the selected data sets and VSAM clusters, according to the DSCBs in the VTOC.
An edited version of information from the VTOC and VVDS is stored at the beginning of the backup, serving as an index of the data actually in the backup, and providing information for allocation of output data sets
The VTOCIX and VVDS may be backed up as data sets, if they are selected by DSF control statements. However, they are not required to be able to restore data sets from the backup, and they are usually not included in the backup.

Tip

Since FDRDSF does not support selection of data sets from your catalogs (CATDSN=) and requires that you know which volumes the desired data sets reside, we recommend that you use Working-with-FDRAPPL to backup data sets selected from the system catalogs.

Data set restores

FDRDSF restores are considerably different from FDRrestores:

You may restore all data sets on the backup, or only selected data sets and/or VSAM clusters. The input to the restore may be an FDRor ABR full-volume backup, or a DSF or ABR data set backup.
The data tracks of the selected data sets may be restored to a different physical location (cylinder and head address) than the original tracks occupied. In other words, you do not have to be concerned about the location of the output data set or the number of extents it is in.
Data sets and clusters may be renamed during restore.
If an output data set (either the original data set name or the new name) already exists, and is large enough, DSF replaces the contents of the existing data set and updates its describing information (VTOC and VVDS information). If it is not large enough, DSF attempts to extend it to the required size. By default, DSF restores an existing data set to whatever volume it is currently cataloged.
If an output data set does not exist, DSF allocates it, automatically making it large enough to hold the contents of the input data set. Usually DSF also catalogs the output data set as well (if the output data set is already cataloged to another volume, DSF does not catalog it unless you instruct it to do so). VSAM clusters must be cataloged when they are allocated, so a VSAM allocation fails if it is already cataloged (but you have an option to delete the existing cluster and catalog the new one in its place).
Output data sets may be directed to various output DASD volumes. Data sets from one backup, originally all on the same DASD, can be restored to many output DASD volumes concurrently (reading the backup only once). FDRDSF JCL must point to the backup data sets, but the output volumes can be identified by JCL or by DSF control statements. You can also identify a list or group of volumes as the target volume; DSF finds one with sufficient space for the data set.
Multi-volume data sets can be restored, but only to the same number of volumes they originally occupied when dumped. Multi-volume VSAM is handled, but only when restored to the original device type.
At the end of the restore, DSF will update the DSCB of the output data set and, for VSAM and SMS-managed data sets, its VVDS entry, so that they properly describe the data that was restored.

FDRCOPY

Program FDRCOPY performs DASD-to-DASD copies of selected data sets and VSAM clusters. Essentially, it does an FDRDSF backup and a restore all in the same step, without the requirement of creating a backup data set, so all the notes on FDRDSF restore above apply. FDRCOPY is described in FDRCOPY - Copy or Move Data Sets.

However, FDRCOPY has the ability to select the input data sets from the operating system catalog. You can specify a data set name, prefix, or data set name mask, and FDRCOPY locates those data sets in the operating system catalog and automatically identifies and processes the DASD volumes required. You do not need to specify either the input or output DASD volumes in the FDRCOPY JCL. You may skip the catalog search and search specified DASD volumes directly, if you wish. If a new data set name is being created, the new name can be formed by adding or replacing one or more index levels in the original name. Additionally, replacement index levels do not have to be the same length as the original indexes they replace.

If you are also licensed for FDRREORG, FDRCOPY includes a function for high-speed reorganization of PDSs (Partitioned Data Sets); this is also called PDS compression. The PDSs to be reorganized can be selected by normal FDRCOPY selection, from operating system catalogs, or volume VTOCs.

Absolute track operations

FDRDSF and FDRCOPY can also dump, restore, and copy data tracks by their physical, absolute track address. Ranges of tracks to be processed are identified by a starting and ending track address (cylinder and head number). In this mode, the original tracks can be restored or copied only to the original track addresses; you cannot restore to a new location on the output DASD with absolute track addresses.

Printing DASD data

FDRDSF has a function to print the contents of DASD data tracks. The printout shows the physical layout of each track, including each physical record and the hardware count field and key field (if present) for each record. You may select the data tracks to print by data set name and/or by absolute track.

SAR

Stand Alone Restore (SAR) is an IPLable program that runs without an operating system, whose main function is to restore FDRfull-volume backup tapes at a time when you cannot execute normal FDRbecause your operating system cannot be IPL’d. This can occur if DASD volumes required for z/OS IPL (such as residence volumes, paging volumes, spooling volumes or library volumes) are unavailable due to hardware or software problems. SAR can also be used to setup new data centers by restoring backups of volumes prepared at another site. SAR is described in detail in Working-with-SAR.

We recommend that you copy the SAR IPL text to an unlabeled tape or to one or more DASD volumes for quick IPL when required. Once loaded, SAR can restore multiple FDRbackup tapes without an additional IPL.

SAR can also create a full-volume backup of DASD volumes on tape. This might be required to backup a non-critical volume so that a critical volume can be restored in its place. Although this backup is in normal FDRformat (described in Full Volume Backups), it does not contain formatted VVDS data, so DSF cannot restore VSAM or SMS-managed data sets from a SAR backup.

SAR can also relabel a DASD volume.

FDRINSTANT

If you are also licensed for FDRINSTANT, it enhances FDR, FDRDSF, and FDRCOPY to provide the ability to take backups or copies that are frozen at a given point-in-time. It allows you to capture a point-in-time image of an online DASD to an offline DASD, effectively preserving the image of the online DASD at that point-in-time. FDRINSTANT can then read the offline DASD and create the required backups or copies, without relabeling the DASD or bringing it online.

FDRINSTANT also enhances FDRCOPY to provide instant copies of data sets when copying between two volumes in a DASD subsystem with a supported hardware replication facility (SnapShot, FlashCopy, or TimeFinder).

FDRINSTANT for various hardware platforms is described in:

FDRCRYPT

If you are also licensed for FDRCRYPT, it enhances FDR, FDRDSF, and FDRABR to optionally create and restore backups encrypted by one of several public (symmetric) key encryption algorithms, including AES (Advanced Encryption Algorithm).

FDRCRYPT also enhances FDRTCOPY to allow you to copy encrypted backups, including the ability to create an encrypted backup from an unencrypted backup, an unencrypted backup from an encrypted backup, or to change the encryption type while copying.

FDRCRYPT is described in FDRCRYPT Backup Encryption.