Re: Newbie: What actions have to be taken when doing a COLD BACKUP?

"peter" <peter01234_at_zonnet.nl> wrote in message news:jgz4a.5215$481.18938_at_amstwist00...
> Hi,
>
> I am expected to do some Oracle DBA work, unfortunately I still quit new
in
> this area
> and I would really appreciate your advice / help in this matter.
>
> I got an Oracle 8.1.6 server (NT4) running a few databases. All database
are
> running in Archive mode.
> We run daily backups on the files system using ArcServe, which also backup
> the Archive redo files.
> My ARCHIVE redo files are taking a lot o space by now and I had to move
some
> of them from the archive directory to another volume.
> I have been told that these archive redo files can be removed (deleted) as
> soon as a "COLD backup" has been done. As far as I have red, a COLD backup
> consist of bring down the database (stopping) to archive a consistent
state
> and doing a backup with ArcServe or just copying these files
> (datafiles/param.files/control files) to a CD-ROM.
>
> My question:
>
> 1.)
> Does my Oracle server somehow need to know that a COLD backup has been
done
> (or is about to start), so that in a case of a recovery (db crash), it
won't
> request or insist to have Archive redo files that have deleted?

Hi Peter,

No (unless we're talking RMAN which I assume we're not).

After restoring the "stuffed bits" of your database, Oracle "knows" which redo logs needs to be applied (or from which redo log) based on the checkpoint information recorded in the header of your datafiles. In a cold backup, these headers reflect the "correct point of time" as the header info and related data within the datafile *must* be consistent a the time of it being backed up, as a closed databases has zip activity.

>
> I may be making a complete mistake, but I would perform a COLD BACKUP by:
> 1.) Ensure that all users have logged off

Nah, bugger that. If you routinely shutdown your database to do backups, they need to learn that they have to nick off and catch up on "The Bill" or something on the telly.

Shutdown immediate is the way to go ...

> 2.) Starting the Enterprise database manager graphical tool, >

If you must ...

> 3.) Stopping the database (shutdown)

So long as it's not an ABORT ...

> 4.) Schedule an ArcServe Job to backup the datafiles / control and param
> files.
> 5.) Deleting the Archive redo files
> 6.) Restarting the database using the Enterprise database manager
>
> Did I forget any import detail?

The only point I would make is that having just the one set of backups and no previous set of archived logs means you are totally dependent on this backup. Any sneaky corruptions in your back and you're kinda stuffed. I would recommend storing on tape (if you must) x number of backups and corresponding redo logs, just in case ...

Couple of suggestions. Don't be reliant on OEM. Investigate RMAN.

Cheers

Richard Received on Wed Feb 19 2003 - 08:00:42 CST