Testing recovery with simulation

This non-destructive option (SIMULATE-YES) performs most of the work of a normal recovery. After reading and merging image copies, log files, and change accumulation files, BMC AMI Recover discards the output and leaves the underlying table space unaffected. Using this option, you can see exactly how a recovery will run without sacrificing data availability.

Recovery simulation provides a way for you to validate that you can recover your application data. You can use recovery simulation to verify that needed recovery resources are valid and available and that log apply can be performed.

The following synonyms are required in BMC AMI Recover syntax when you specify OPTIONS SIMULATE YES:

• SIMRCVR TABLESPACE, INDEXSPACE, or INDEX for RECOVER TABLESPACE, INDEXSPACE, or INDEX (SIMRCVR)
• SIMRBLD INDEX for REBUILD INDEX (SIMRBLD)
• SIMRCVR UNLOADKEYS for RECOVER UNLOADKEYS (RECOVER-UNLOADKEYS-command)
• SIMRCVR BUILDINDEX for RECOVER BUILDINDEX (RECOVER-BUILDINDEX-command)

You can use BMC AMI Recovery Manager for Db2 to build the JCL for recovery simulation. For more information, see Recovery Management for DB2 documentation.

Operational considerations

When you specify OPTION SIMULATE YES in an BMC AMI Recover job, BMC AMI Recover proceeds with all recovery activities that are not destructive. Destructive actions that could affect real database objects or the recovery environment are simulated, suppressed, or executed in the temporary data sets. The following activities are included:

• Reading and sorting log records
• Merging image copies, log records, and change accumulation files
• Extracting index keys

BMC AMI Recover does not stop any table spaces or indexes during simulation mode.

In the following recovery scenarios, BMC AMI Recover creates and uses temporary data sets (SIMDBC or SIMDBD), instead of real spaces (DSNDBC or DSNDBD), for simulation:

• Recoveries from Inline, instant snapshot, or flashcopy image copies
• Backout, LOGONLY, or LOGAPPLY ONLY recoveries

When you simulate recovery of inline, instant snapshot, or flashcopy image copies, BMC AMI Recover snaps the image copy into temporary data sets to process the simulation.

When you simulate a backout, LOGONLY, or LOGAPPLY ONLY recovery, BMC AMI Recover snaps the original spaces into temporary data sets to process the simulation.

BMC AMI Recover performs the following tasks for table spaces and for indexes:

• Reads full and incremental image copies that are required for recovery
• Reads change accumulation files that are required for recovery
• Simulates applying log records, change accumulation log records, or both
• Extracts index keys for any index rebuilds that are required

BMC AMI Recover processes the extracted, sorted keys and builds each index page in storage.

BMC AMI Recover does not perform the following activities:

• Write any output pages to DASD (if you are not using temporary data sets for a simulation of recovery)
• Write any output image copies
• Write to BMCSYNC or BMCUTIL
• Register any events in SYSIBM.SYSCOPY
• Set or reset any pending flags

Limitations

Use of recovery simulation has the following limitations, most of which result from not performing any disruptive activities on the spaces that are involved.

• The following BMC AMI Recover features are not supported in recovery simulation:
  • ANALYZE ONLY or ANALYZE SCANONLY
  • LOGSCAN

  • Point-in-time recovery

    Important

    Simulation of point-in-time recovery is indirectly supported by specifying a log point with the SIMULATE option. In this case, BMC AMI Recover simulates recovery of all objects in the SYSIN to the same log point. Simulation of point-in-time recovery is also provided by the OPTION RECOVERYPOINT option if the Recovery Management for Db2 solution is installed.

• Simulation runs are not restartable.
• The requested recovery scenario can require unloading keys from the real table space (partition) if REBUILD or UNLOADKEYS is requested for the table space (partition) not recovered in the same step. Such unload operations involving real table spaces (partitions) will be suppressed in simulation mode.
• Objects may be in any initial status and there is no impact on the status or contents of the real database objects.