Installation and Configuration Best Practices › Performance and Maintenance › Backup CA TPX VSAM Files

Backup CA TPX VSAM Files

Backup CA TPX VSAM files periodically.

Business Value:

Backing up the VSAM files provides a recovery point if the active VSAM files become unusable.

Additional Considerations:

All CA TPX regions which access the VSAM files being backed up should be taken down while the backups are being run.

Regular VSAM Maintenance for CA TPX VSAM Files

Use VSAM tools such as the IDCAMS utility on a regular basis.

Business Value:

This preventative maintenance can help avoid corruption of VSAM files and improve performance by removing excessive CA/CI splits, for example.

This recommendation is a general VSAM best practice that is important for CA TPX.

Additional Considerations:

Frequency of this maintenance will depend upon the amount of change activity. A REORG using the IDCAMS utility should include:

• Taking a backup of the VSAM file beforehand
• Performing a DELETE or REDEFINE of the VSAM cluster
• Restoring the VSAM file from the data portion of the backup file; letting the INDEX be rebuilt to cut down on possible VSAM INDEX corruptions

This preventive maintenance procedure (REORG) mitigates Control Area(CA) and Control Interval(CI) splits and VSAM file corruption.

Note: If the CA or CI splits are excessive even after a REORG has been done, increasing the FREESPCE parameter in the VSAM cluster DEFINE will help to alleviate this problem. Excessive CA/CI splits most typically occur during a new install when performing a high volume ADD maintenance activity for information stored on the CA TPX VSAM files. You can lower the FREESPCE parameter when the high volume of activity has ended.

When you are performing a REORG of your CA TPX VSAM files, you should first review the DASD definitions and make sure the current definitions are still adequate for the volume of data stored on each CA TPX VSAM file. If you are at or near the maximum space capacity, you should increase your DASD specifications so that the next VSAM REORG DEFINE of the cluster reflects the new DASD specifications or requirements for the VSAM file.

Sample JCL members for CA TPXVSAM file backup (VBACKUP/LSBACKUP*), file restore from file backup (VRESTORE/LSRESTOR*) and cluster definition (VADMIN1/VADMIN2/VMAIL/VNOTES/VVIEW) can be found in the CB0VJCL library.

Note: If your CA TPX VSAM files are managed by LSERV, refer to member $INDEX for a list and definition of subsequent members provided in the CB0VJCL library.

We also recommend that you run the CA TPX Batch Reset Integrity process (refer to library SAMPLIB, member BATCHINI for sample JCL) after any CA TPX VSAM file REORG/restore process before starting CA TPX.