Re: Backup Recovery Strategy for Large Database

In article <D2yuwt.7pB_at_lanier.com>, Don Vick <dvick_at_lanier.com> wrote: ...
>>I need to develop and implement a backup/recovery strategy for a large
>>Oracle application. This will be a global system and is required to be
>>available 24 hours a day, 7 days a week. The platform is HP/UX and

Is it really 24/7 or can you be down for a few minutes?

>>I would like to know what backup/recovery method you use, have you had to
>>recover, what advice/cautions/recommendations/etc you can share. Also,
>>with the shadowed disks, is it possible to de-shadow and then perform a
>>backup on the former shadow sets?
>
>We use this technique for backing up a 20+ gigabyte database that has
>stringent uptime requirements (though not 24x7 yet). At an opportune
>moment, we mirror the disks containing the database, then bring down the
>database, separate the mirrored drives, and restart the database. The
>database is down for less than five minutes, and we have a complete static
>image that can be backed up to tape later. Maybe you can adapt this to a
>hot backup strategy.
>

We use the same tactics above for small production databases for some of our customers. For our new database (60 - 100 Gb) we might go for hot-backups.

You have to put the database in archive mode and when backup is due, alter the tablespaces you have to backup to BACKUP status. Then split your mirrors, de-alter the tablespaces to online, and backup your database.

The backup can take a lot longer than a morning or a night. After the backup you can 're-silver' the mirrors. You'll be saved all times. The only dis-advantage with hot-backups is the time to recover. You have to consider this because the time you loose with cold-backups is (often) much less than recovering a hotbackup. Choose carefully and think about the consequences.

Just my fl 0.05 contribution

-- 
Peter

-------------------------------------------------------------------------------
Peter van der Kooi		| Telephone: +31 50 851046
PTT Telecom BV			| Telefax  : +31 50 851078
I&AT				| E-mail   : peter_at_telecom.ptt.nl
P.O. Box 188			| DISCLAIMER: This statement is not an official
NL-9700 AD Groningen		| statement from, nor does it represent an
The Netherlands			| official position of, PTT Telecom B.V.
-------------------------------------------------------------------------------