We have a new system installed Oracle 8.1.6. Now we are considering the method of Backup/Recovery.
In our system 2 disks and 1 tape device can be used for backup. And I think there are 2 ways to use them:
1). 1 disk : archive log;
1 disk : backup using by RMAN;
1 tape : backup's backup
2). 1 disk : archive log;
1 disk : the copy of the archive log;
1 tape : backup using by RMAN;
I don't know which is better? which is common?(The data size is about 20GB)
Can some one give me some advices?
This all depends on how the disk is layed out. Is disk#1 mirrored? If not, option #1 would be out IMHO because your archived redo logs do not have any redundancy. If disk#1 is mirrored, option #1 would yield the best performance.