RE: Differential incremental backups - Do you really use them?

From: Storey, Robert \(DCSO\) <"Storey,>
Date: Mon, 22 Mar 2010 12:52:11 -0500
Message-ID: <>

So, I'm curious. If I read your schedule right, you have a yearly backup? Are you setting a time frame so that you only backup the database from a scn to another scn, based on the year?? Why would you do that? I'm just curious how you are doing a "yearly" backup.  

And I'm assuming that since you have this kind of backup setup, that you have available ever archive log for 7 years? I am again assuming that if you worst nightmare happened and you had to revert to a backup you made 3 years ago, that you can recover forward to current time?  

Do you have some business reason for keeping backups for 7 years? HIPPA??   I have a small db that I'm just now starting to use RMAN for. A full backup of takes 22 minutes. I don't do enormous amounts of DML or changes a day, so not sure how big an incremental will be. I plan to implement incremental's to make for better storage utilization in our disk farm.      

[] On Behalf Of Allen, Brandon
Sent: Monday, March 22, 2010 11:25 AM
To:; Subject: RE: Differential incremental backups - Do you really use them?  

I still don't understand the hesitancy to use incremental backups even on smaller databases - they are very simple, and even on a small database can still add up to a significant savings of resources especially if you keep a lot of backups like I do. I keep all daily backups for 35 days, all monthly backups for 13 months and all yearly backups for 7 years. The monthly and yearly backups are full of course, but for the daily backups, I only do a weekly full and incremental all other days, so that cuts down the resource usage on my server, SAN, network and backup storage media by almost 6/7, or 85% and costs me nothing. Running full backups all the time just seems wasteful to me. If you're into the green IT movement, then that should be taken into consideration too - all that extra CPU and I/O activity means extra energy usage & cost too. I doubt you take full backups of your PC every day - you probably do incremental backups instead, so why not apply the same idea to your databases? It seems to me the typical approach is backwards - incremental backups should be the default, and daily full backups should only be used if there is some compelling reason to do so - for example if you tend to change a large percentage of the blocks in your database.  



[] On Behalf Of Pani Babu

looks like exceptionally large databases or backup and other infrastructure restrictions may leave one with no other choice than to use incremental backups.    

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Received on Mon Mar 22 2010 - 12:52:11 CDT

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