Re: How to replicate a Database?

From: Damien <spanish.inquisition_at_altavista.net>
Date: 26 Nov 1998 16:57:19 GMT
Message-ID: <01be195e$78fe3b20$2bcbfcc1@moi>

> We are running a mission critical Oracle database. We have 2 dedicated
> serves running Oracle 8.04 on NT4.0. How can we setup the primary Oracle
> server to replicate all its data to the backup Oracle server. We would
like
> to have hot standby. Does Oracle offer some tools to do this and how much
do
> they cost. I've read about Oracle FailSave but this requires MS Wolfpack
and
> NT 4.0 Enterprise which we don't have.

On ora734/Solaris, I used the standby mechanism. It relies on the archivelog feature.
Archivelogs are transferred (e.g. with rcp on Unix) and replayed to the 2nd server.
The 2nd database runs in standby mode and it only has the capability to replay archivelogs. It can't be accessed for queries.

Shortly, setting a standby DB consists in : * shutting down the 1st DB;
* copying the tablespaces from the 1st to the 2nd server (e.g. with rcp on Unix) ;

* generating "standby control files" on the 1st server;
* copying these files on the 2nd server;
* activate archivelog mode ont the 1st DB;
* start the 2nd DB in standy mode (it's not fully mounted).
* start normally the 1st DB;
* activate a mechanism of your choice for transferring the archivelog files

and
  having the 2nd DB replay them.

Refer to your Oracle documentation for details and syntax.

Activating a standby DB so it can be normally accessed (when the 1st DB crashes)
is NOT reversible. Once it has been mounted, you have to repeat the full process above
to re-create a standby architecture.
Enjoy !
Damien. Received on Thu Nov 26 1998 - 10:57:19 CST