Re: EMC Snap Clones vs. Data Guard

DA Morgan wrote:
>
> I'd still go with RMAN. I'd want to recover Oracle objects ... not
disk
> blocks.

The elapsed time, io utilization and cpu cycles required by RMAN to directly backup to (disk or tape) a database of any significant size is not to be overlooked. The recommendation above appears somewhat naive and does not appear to address many of the op's included considerations.

Dusan's contribution seems to be much more on target in my opinion.

My recommendation is to consider using a combination of both disk BCV's and RMAN.

Take a look at this url:

http://www.oracle.com/technology/deploy/availability/pdf/RMAN8i_BCV.pdf

(Let's not get in a big flamewar that it says 8i techniques described work well in 9i also and probably 10g as well).

The design that this doc has is pretty basic and should be changed to fit your environment. Lots more different BCV's.

The basic idea is that you can have disk "copies", break the mirrors, take an RMAN backup of the broken mirrors, without impacting the environment.

Then you resynchronize some of your BCV's (probably ctl files and online logs) while you leave the rest of the BCV's split off.

If you have a problem one of your primary recovery techniques involves disk BCV's. There are already "there" and ready to use.

SRDF is an excellent additional supplement to this kind of backup and recovery setup (as Dusan noted).

There's a bunch more info you can find by googling around with words such as "oracle bcv integration rman timefinder backup recovery" (try various combo's).

My advice to the op. Do some serious research and legwork and thinking before going very far down any specific path.

The scenario the url describes is a very complicated one. Can it work well ... you bet your bippy. Is it easy to setup and test or complicated (you know the answer).

Do people in the real world run like this? Oh yeah.

10g does appear on the surface to have some attractive design alternatives to what's described here. The op said they are running 9i.

Believe it or not many of us have restrictions about what oracle releases we are allowed to consider and implement. Received on Thu Apr 07 2005 - 07:19:46 CDT