Re: Q: Backup solutions

Don,
Here's the deal, we had a similar requirement. Looks like you are under the impression that you HAVE to split the mirror in order to do HOT backups. That is UNTRUE.

You can do hot backups without doing a "split" of the mirrors. The reason some shops break the mirrors is to reduce the time of HOT backups. If a database crashes during the HOT backup you may have to do a full recovery of the database. If you are planning to do Full database backup Online, it may take few hours and you are in the risk zone during this period. Instead you can take the database into Online backup mode split the mirror and comeback online and backup the broken mirror.

The option that I recommend is to bring the database down break the mirror and bring the database backup (while the databases are running in archivelog mode). This process doesn't take more than 5 minutes, and you have a clean backup on the mirror, and backup the mirror on to a mass storage device or tapes. If you want to take minimal chances you can do three way mirroring as we do, where in, you will have your disks mirrored even after breaking off one mirror.

As far as other backup tools for Oracle, check out SQL*Backtrack (BMC?), they supposedly do backup of only the dirty datablocks in the database there by reducing the backup storage.

Thanks,
  Kittu.

Don (name_at_isp.dom) wrote:
: We have jumped into the world of Oracle 7.3 on a SUN Ultra Enterprise
: server. We are currently using striping, double mirrors, shared disk
: arrays, and a second server. We've implemented the Veritas
: First-Watch high availability solution for max up-time.
 

: We believe we would like to do HOT backups. It sounds like that would
: involve breaking the 2nd mirror, backing it up, and remaking the
: mirror. This server can not afford ANY downtime even for backups.
: Our backups will involve tape rotations to an "on-site" hazard
: hardened vault, as well as an "off-site" hazard site. The backup
: needs to be done in such a manner that system restoration could be
: done in the SHORTEST possible time. Again, minimum down time.
 

: Is there any particular backup solution (software and/or hardware)
: that you have found to be VERY successful, or a dismal failure?
 

: All of our AIX systems (16 at last count) are using C-TAR as the
: backup solution, but most of these systems can easily tolerate
: downtime.
 

: Why the emphasis on zero downtime? We are a group of 4 hospitals.
: Doctors and especially nurses just don't tolerate a down system - it
: does not matter why the system is down.

: Thx, in advance, for your thoughts.

: Don Dealy, II
: Legacy Health System
: Portland OR USA
 

: email: dondealy_at_teleport.com
Received on Thu Sep 25 1997 - 00:00:00 CDT