VERIFY overview

The Verify Recovery Assets function (VERIFY) examines the RECON data sets and the IMS Recovery Expert repository to identify the recovery assets that are required to recover one or more databases.

Specifically, the VERIFY function performs one or all of the following functions:
  • Lists or prints the recovery assets that are required to recover the specified databases
  • Allocates all recovery assets to ensure that they exist
  • Opens all recovery assets to ensure that they are valid

The VERIFY function requires that you specify the target databases by using the DBLIST supporting function.

The VERIFY function can use the RECON copy data sets that are created by the RECONCOPY supporting function, or the data sets identified on the ALTRECONS supporting function.

Note: Use either RECONCOPY or ALTRECONS in conjunction with VERIFY to prevent input/output (I/O) to the live RECON data sets.

Processing System Level Backup Image Copies

The RECON can contain Image Copy records that represent System Level Backups (SLB). The following considerations pertain to using VERIFY to process SLBs.

  • The data set name for the SLB Image Copy is symbolic only and is formatted as follows: 
    SLB.Ixxxx.Dxxxx.dbdname.ddname

    These data sets are never cataloged, nor does any function try to allocate or open them.

  • When USESLBIC(N) is specified, RECON Image Copy records that represent SLBs are treated by VERIFY no differently than any other Image Copy records with one exception: VERIFY does not verify as to whether they are cataloged.

    You can use the VERIFY function with the LIST option to determine if there are SLB Image Copy records in the RECON.

    IMS Database Recovery Facility VERIFY, IMS Database Recovery Facility Extended Functions VERIFY, and IMS Database Recovery Facility Extended Functions HCHECK functions all recognize these data set names as symbolic only.

  • When USESLBIC(Y) is specified, and whenever necessary, IMS Database Recovery Facility Recovery, IMS Database Recovery Facility VERIFY, and IMS Database Recovery Facility Extended Functions VERIFY functions issue a NOTIFY.IC command to DBRC for the most recent SLB that exists relative to the function’s specified time parameter (for example, RCVTIME or "current").
  • It is a best practice to delete any Image Copy records that represent deleted SLBs.

    Otherwise, the VERIFY function would consider these Image Copy records as representing a usable backup. This correlates with the fact that IMS Database Recovery Facility Recovery and IMS Database Recovery Facility VERIFY would also consider these records as valid and attempt to use the deleted SLBs.

  • Another possible situation occurs when an SLB exists, yet there is no RECON IC record that represents it.

    The VERIFY function with any of its options (LIST, ALLOC, OPEN) cause representative Image Copy records to be written to the RECON.

  • If available, IMS Database Recovery Facility Recovery uses the fast-replication volume(s) for recovery. If fast-replication volume(s) are not available, IMS Database Recovery Facility Recovery uses the offload data sets.

    If there are offload data set(s), they are displayed on the report. This does not indicate that they will be used for recovery. It just indicates that they are available if needed.

Reference: SLB offloaded data sets

SLBs exist either on a fast-replication capable device(s), or have been offloaded from the fast-replication devices onto sequential data sets on tape or DASD.

When on the fast-replication device, the data is an exact replica of the backed up data except that the data sets are not cataloged. During the offload process, IMS Recovery Expert creates one sequential data set per device and catalogs them on the offload volumes. An SLB can be used for recovery whether it resides on the fast-replication capable device(s) or the offload data sets.

For more detailed information, refer to the IMS Recovery Solution Pack for z/OS®: IMS Recovery Expert User's Guide.