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RE: RMAN-NetBackup without an RMAN Catalog

From: Joel Garry <>
Date: Thu, 14 Oct 2004 13:28:13 -0700
Message-ID: <>


Your answer is one of those "just because we've always done it that way" answers. And that is not a good answer - RMAN should be able to restore a backup from only 5 years ago. Why do you remove the old stuff? Space? These days, people say things like "storage is insanely cheap, why we make it from sand! " (Celko) But of course, RMAN is simply moving stuff around, tape v. disk is a straw man. Why do we migrate? Because the new stuff can't handle the old stuff - but it can handle external tables. Why should migration be necessary? What must we think of someone who says a version is the last version we will ever need? (Larry E.)

It boils down to Oracle not wanting to spend the bucks to allow backward compatibility, and no one yet seeing the value of designing software for the ages. Even if nothing else will grant the latter, restoration software must deal with aging. I think RMAN should be able to deal with multiple versions, restoring the O install if it has to. Well, maybe not without a catalog... :-)

Shouldn't be any harder than reconciling any other kind of distributed transaction conflicts. Why can't RMAN save a [n O equivalent of a] tarball of the installation as an external table?

Some systems do go for 5 years without being migrated, too. Perhaps more should. (My bias is to be a release or so behind for production, if you are curious. But that is pragmatic, not what should be. This is not the best of all possible database worlds, and we should be working to get closer to the optimal. A simple question like the OP can show what is missing.)

I used the example of a converted system, not as a red herring, but to fend off suggestions of a properly designed system being able to produce five-year-old reports. For example, system A is replaced by system B and moved to offline storage, but five years later someone needs to get something from system A, so RMAN should do that. I think that is a perfectly reasonable request, even if it means manually re-installing 9i. Archiving can apply to systems as much as data. 5 years just isn't that long for data.
-----Original Message-----
From: Mercadante, Thomas F [] Sent: Thursday, October 14, 2004 11:28 AM To: Joel Garry;
Subject: RE: RMAN-NetBackup without an RMAN Catalog


He wasn't talking about a converted system. He was talking specifically about restoring an Oracle backup from 5 years ago. We are speaking specifically about an Oracle database. When we migrate the database to the
apply new version, there is no copy of the old version around - it has been
migrated. And the old backups become obsolete. And typically, the old Oracle home gets removed. So restoring an older version of the database would require keeping the Oracle software around for that amount of time.
Not very likely.

The correct answer is a properly designed database that can produce reports
of what the database looked like 5 years ago - like specific account balances. That would be the ticket!

Tom Mercadante
Oracle Certified Professional

-----Original Message-----
From: Joel Garry [] Sent: Thursday, October 14, 2004 2:20 PM To:
Subject: RE: RMAN-NetBackup without an RMAN Catalog

>From: "Mercadante, Thomas F" <>
>You have to admit that this may never be available. Think about it.
>will be migrating to new releases about 4 times between now and 5 years
>now. Rman version 13x would probably choke and puke anyway when it
tried to
>restore the version 9i controlfile! :)
>Tom Mercadante
>Oracle Certified Professional


I see stuff all the time where people have 5+ year old systems that have been converted, but they still keep the old boat anchor around so they can
look at stuff - sometimes to say "The old system did this, make the new system do it!".

Between legal requirements and archival requirements, I don't think it is
strange at all that someone might want to restore to 5 years ago. I think
it is very strange that a major database vendor might not be able to with
their primary restoration tool.


Received on Thu Oct 14 2004 - 15:24:08 CDT

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