Re: Oracle + LVM = Mirrored Backups?

When you have HP-UX and Mirrordisk UX you can use the following procedure to take a full off-line backup with a minimum downtime.

1. Shutdown the db
2. use "lvsplit" to "unmirror" the lv's. This will create several "backup-lv's"
3. Startup the db. It's now running in a not-mirrored state. The db is available for the users or batch jobs.
4. use fsck + mount to create usable file-systems from the "backup-lv's".
5. take a backup of the "backup-filesystems"
6. dismount the "backup-filesystems"
7. use lvmerge to synchronize the mirroring.
8. Done, you have an offline backup. The db is running again on mirrored lv's.

Be carefull with the lvmerge command. The order of the lv's you specify determine the lv's that will be syncronized.

Hopes this helps.
Gert

<fpuhan_at_my-deja.com> wrote in message news:812c83$pm9$1_at_nnrp1.deja.com...
> During a recent discussion with a tech from Hewlett Packard, I was
> informed that it is possible to perform backups on VLDBs with a minimum
> of downtime by using LVM (Logical Volume Manager) to create mirrored
> copies of Oracle's data files, then by "breaking" the mirror, backup the
> mirror copies of the data files, and the re-sync the mirror once the
> backup is complete. The total downtime I'm told is in the minutes, if
> not seconds.
>
> This looks like a potential answer for me to offer to some of my
> company's clients who are running multi-gigabyte databases, where backup
> time stretches into the hours.
>
> Does anyone know of any white papers, web sites, or detailed information
> on how to do this? If it helps, our clients are using HP-UX, either
> 10.20 or 11.00 and Oracle 7.3.4, or 8.0.5.
>
> Many thanks in advance,
>
> =Fred=
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
Received on Fri Nov 19 1999 - 14:44:56 CST