Zero Downtime Backup of MaxDB database with HP Data Protector

Appendix C

The following is a complete Data Protector session report which shows the benefit of deploying the

ZDB_ALWAYS_POST_SCRIPT omnirc variable on the application server. There was a problem with

the resolution of the storage volume and so the storage volume was not resolved. As a consequence

Data Protector cleans up the procedure, bypasses the application level pre-exec script, and jumps

directly to executing the application level post-exec script.

This behavior is a direct consequence of setting the ZDB_ALWAYS_POST_SCRIPT omnirc variable

to 1, which means the application level post-exec script is always executed whenever the backup

specification is run. By default, the variable is set to 0.

Note that the MaxDB instance continues to work normally even though there is an array volume

resolution problem. Invoking the application level post-exec script which resumes MaxDB’s logwriter

process has no detrimental effect on the running MaxDB instance. In fact, resuming MaxDB’s logwriter

process has no impact on a logwriter process that is already running. Compare this with the impact of

suspending the MaxDB logwriter process on an already suspended logwriter process (see Appendix B

on page 41

[Normal] From: BSM@hpu069.deu.hp.com "zdb_tpc003_maxdb_bkp_serv" Time: 4/8/2009 4:05:25 PM

Backup session 2009/04/08-4 started.