Re: RMAN or Hot Backup

From: Michael Austin <>
Date: Thu, 26 Mar 2009 20:17:30 -0500
Message-ID: <4NVyl.23099$>

Mladen Gogala wrote:
> On Thu, 26 Mar 2009 17:24:28 -0500, Michael Austin wrote:
>> They are morons and should be relieved of their duties and COMPETENT
>> talent hired to replace them.

> I would disagree, and bitterly so. There are reasons for using hot
> backups, especially in this economy.


  1. HBM uses 2x disk space - unless you try to compress and then it comes down a bit - but only if you know how to use named pipes etc...
  2. RMAN does compression - AND it ONLY backs up data blocks - not empty space.
  3. HBM does not catalog the backup - so you have to keep track of it
  4. Disk-to-Tape (either HBM OR RMAN) is a catastrophe in the making! -- you stay away from the snake when it has shown that it bites really hard and FAR too frequently to be of any value other than the "oh %$#_at_%@$# someone deleted the backup to make space... at the same time your db crashes" - and then you better PRAY that the tape works.
  5. RMAN restore is INFINITELY more flexible and provide more options than HBM.

Economically speaking, use RAW/ASM, **if done correctly** will actually help the over-burdened DBA by almost eliminating "tablespace full" and a host of other very time-consuming "file/tablespace maintenance" chores. Then, RMAN is going to be your only option. Today's DBA MUST start using the tools afforded them in some of the later versions ESPECIALLY in today's economy where we are being asked to do the work of 3 and 4 people. Gartner says that the average for DB:DBA should be in the 20:1 ratio - I know of shops that are in the 70+:1 ratio. Trying to get anything actually accomplished is futile.

I stand by my previous statement - because they fail to see the bigger picture... Short-sightedness and frugality when it comes to the data that runs your business IS suicide - [alter company drop dba; - or worse: alter location drop company;] Received on Thu Mar 26 2009 - 20:17:30 CDT

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