RE: RMAN and filesystem backups

From: D'Hooge Freek <>
Date: Fri, 6 Nov 2009 14:36:40 +0100
Message-ID: <>

Acutally, you would need to have 2 times the size of the database on disk. You my only remove the first backup if the second one is completed successfully. Otherwise, If the backup from disk to tape of the first backup failed, you have no (recent) backup on tape anymore.

We use this type of configuration for several of our customers, but we normally specify that we need 3 times the db size (+ the archivelogs) of diskspace. I don't like it very much myself, as it requires you to make sure the filesystem backup is done after the rman backup is finished and (this is the difficult part) make sure that it stays this way.

Freek D'Hooge
Oracle Database Administrator
tel +32(0)3 451 23 82

From: [] On Behalf Of Guillermo Alan Bort Sent: vrijdag 6 november 2009 12:25
Subject: Re: RMAN and filesystem backups


    I am working on backup improvement project for a very big company and we have this kind of backup in many sites. It beats the hell out of 'BEGIN/END backup' and provides an actual real backup (which export does not) plus it is rather easy to move to a tape subsystem (i.e. TDPO, NBU, etc)

    However, consider that it requires about twice the space of the database just to keep one online backup. (could be more, could be less, but in average it's the same space as the DB). It requires careful synchronization of the tape backup and RMAN backup, since if you start taking the tape backup before RMAN is finished you will most likely end up with an invalid backup and worst of all you won't know about it. If you implement this kind of backup, I'd suggest monthly recovery tests (i.e. get a clean server and perform a full recovery and any PiT recovery you might need).

    As usual, if you can afford the integration agent for oracle (mml) it's far better than any alternative.

Alan Bort
Oracle Certified Professional

On Thu, Nov 5, 2009 at 3:55 PM, Fred Tilly <> wrote: All,

Has anyone set up an environment where they run RMAN (hot) backups to disk and then move the backups to tape using a standard filesystem backup, then remove the older backups from disk.

Does anyone see any problems with doing this ?




Received on Fri Nov 06 2009 - 07:36:40 CST

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