Q: Backups

I'm on a team that just finished development of a system that acts as a repository for data that is collected from other systems. Some of the data is stored in an ORACLE database and some is stored as text or TIFF files. The system is about to go into production so they want me to come up with a backup stagegy.

The database is 3Gig and is on RAID 5. The text and TIFF files will eventually (in about 3 months) add up to about 3Gig and is also on RAID5. (Text and TIFF files more than 3 months old are moved to optical and don't need to be addressed in the backup stategy.)

Since we really want 7x24 availability, we don't want to bring down the database for backups. Also since we're on RAID, we're hoping that we'll rarely need to restore. Finally, almost all of our data is coming from other computer systems and they could send of duplicate copies of recent data in the event of a catastrophe.

We're considering doing backups just once a week. But we don't really want to incur the overhead of being in archivelog mode all the time. What would happen if we use NOarchivelog mode all week, changed to archivelog mode, did online backups, then changed back to NOarchivelog mode?

Since I also need to backup the text/TIFF files at the same time as the DB. I want the DB backup to be consistent with the other file backups. Does archivelog mode plus telling Oracle that I'm starting a backup prevent the tablespace data files from changing during the backup?

The only other alternative I've come up with is to change all application program (written in Pro*C) so that they have a "read-only" mode. But that means trusting the programs to not update the DB while I'm backing up. This sounds too error prone to be trustworthy.

Any suggestions?

Carol Fetters
cfetters_at_iac.net Received on Tue Jul 18 1995 - 00:00:00 CEST