refresh.pl - Compute tape volumes needed for WM(S/Q) refresh
refresh.pl <SAP-Instance> <split-time> [-t|-v] [-f] [-w <window>] [-s <count>] [-c <size>]
SAP instance backups made using SAP's brtools suite are occasionally used to clone such instances. This utility figures out which tape volumes are needed to perform such a cloning operation.
Given a master SAP instance name and point-in-time to be used as the reference state, refresh.pl goes through and works backwards from that poin-in-time to find the most recent SAP backup immediately preceding the cut off. As this backup is located, a list of intervening archive log backups is maintained as well. The final list of tapes then covers the main database backup as well as all required archive logs.
Provide terse output. This pretty much boils down to tape volume ids only.
At the other extreme verbose output will show exactly what volumes are needed for what reasons.
Normally refresh.pl wants to include at least one extra set of archive logs past the split-time to ensure all necessary data will be available to the DBA's when rolling the database forward from the backup. Should such an extra set not be available, the -f option will force refresh.pl to proceed and list volume ids after all.
Almost always, a single brbackup run results in multiple NetBackup jobs. With the default settings refresh.pl assumes all such NetBackup jobs started within a 10 minute window. The -w option allows you to change this number.
If you know the most recent SAP backup is corrupt or the tapes onto which it is written have been damaged, providing refresh.pl with skip count will have it ignore that many SAP backups as it scans backwards in time. Note that the intervening archive logs are still needed!
A key item in determining when an SAP instance backup completed is the fact that once the actual database files have been written out, a small set of files is written in a separate NetBackup job. To distinguish between the bulk data and this bit of control information the assumption is made that the control information takes up less than 5 MBytes. The -c size option lets you change this to some other number of MBytes.
Winkeler, Paul firstname.lastname@example.org
Copyright (C) 2002 Paul Winkeler