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How many standby DBs can you have ? I need 2 !!!

Henrique Silva_3
Regular Advisor

How many standby DBs can you have ? I need 2 !!!

We are running 8.1.7, and I am implementing an Oracle standby solution for drp.

now, I wanted to also have a local standby server, close to the production one, where I could run my reports from, and do my backups from ( have not implemented RMAN yet ).

now,I was under the impression that I could only have one stand by db, but read here of multiple ones.

Do you have any docs where I can how to implement that ? I was going to use BCVs to get that local copy of production going, but if I can set up two stand bys ( one local, one remote ), then, this would be perfect.

Also, does anybody have any experience with omniback and rman integration ? I hear it is prety smooth !!!


Henrique Silva
"to be or not to be, what was the question ???? "
Ian Dennison_1
Honored Contributor

Re: How many standby DBs can you have ? I need 2 !!!


Have integrated OmniBack and RMAN, but had an immense amount of problems getting it set up (Security is a real pain to get sorted so the Users have rights).

The thing I did not like about it was that RMAN controls the backups and restores, and just uses OmniBack as a conduit. So any restore work needs to be done at the RMAN level. To me, it seemed we were splitting the Media Management and Backup Management.

Oraclei 9i will apparently allow a standaby database to be opened in Read only mode while still applying updates. You could combine the functionality of both databases into one single database.

You can have more than 1 standby database if you ship a copy of the Redo Logs to each of them.

Check out this link for news on OmniBack 5.1.

Share and Enjoy! Ian
Building a dumber user
Honored Contributor

Re: How many standby DBs can you have ? I need 2 !!!


Yes, you can maintain a standby database in a location that is geographically remote from the primary database, or maintain several standby databases in geographically diverse locations.

Although a standby database can be synchronized with one and only one primary database, a single primary database can support a theoretically unlimited number of standby databases. These standby databases are separate and independent, and can reside on multiple machines or on a single machine.

How to use backups to create Standby database
Each standby database must be created from a backup of the primary database. This backup can be either consistent or inconsistent, open or closed.

You can also use a single backup of the primary database to create an unlimited number of standby databases, although the various standby databases in the environment do not have to be created from the same backup. For example, you can create one standby database from a backup of the primary database taken on January 20 and create another standby database from the backup taken on June 20. So long as you have the archived redo logs required to perform complete recovery of a backup, then it can serve as the basis for a standby database.

However note that there are limits Imposed by Automatic Archival to Standby Sites.
In a managed standby environment, the primary database can automatically archive to a maximum of four standby sites. Consequently, you can simultaneously run a maximum of four standby databases in managed recovery mode in any given standby database environment.

Although automatic archival limits the number of standby databases that you can maintain in managed recovery mode, it does not limit the number of standby databases that you can maintain in manual recovery mode. For example, you can configure the primary database to archive automatically to four standby sites, then use operating system commands to copy archived redo logs to five additional standby sites. Consequently, there is no theoretical limit to the number of standby databases that can support a given primary database.

If you need more information on how to create these standby databases, please let us know.

Hope this helps!

Best Regards
No person was ever honoured for what he received. Honour has been the reward for what he gave (clavin coolidge)
Steven E. Protter
Exalted Contributor

Re: How many standby DBs can you have ? I need 2 !!!

Our current production environment:

D380 1G mem, lots of disk.

We're running three Oracle instances on the box.

One is production.

One is shut down as a standby and for migrating major conversions to productoin. New database config goes to the shut db first along with code.

The third instance is training, which is supposed to be a copy of production. Its supposed to have less records.

The three instances aren't very large, but they cover 30 G of diskspace.

We can use the shutdown instance for backups and such.

We are migratting to rp 5450 boxes and plan the same database load but with dual processors and four times the memory.

I've tested the omniback/oracle/rman integration and its pretty slick. If memory serves you need to be at a versoin above 3.5. Better off with 4.X latest patches I think.

Of course with Oracle, you need all the patches.

Read this post all posters for some more sickening detail with regards to Oracle.,,0xf92d5bd3782dd711abdc0090277a778c,00.html


Steven E Protter
Owner of ISN Corporation