logical standby and streams, is it possible to configure streams on a logical standby? Options

[pkoehle]

Source DB is logical standby 10.2.0.5
Destination DB is 11.2.0.3

Is it possible to set up streams on the logical DB to replicate some schemas to the 11gR2 DB?

[burleson]

>> Is it possible to set up streams on the logical DB to replicate some schemas to the 11gR2 DB?

You are asking if you can replicate to a newer release?

Yes, I think so . . . .

[pkoehle]

>> Is it possible to set up streams on the logical DB to replicate some schemas to the 11gR2 DB?

You are asking if you can replicate to a newer release?

Yes, I think so . . . .

There's a 10.2.0.5 primary DB (where supplemental logging is enabled) replicating to a 10.2.0.5 logical standby.
Now we want to replicate some schemas from the logical standby DB to a remote 11.2.0.3 DB.

So I want to know if there are any restrictions for enable supplemental loggin (as needed by streams) on the logical standby.

[burleson]

Hi,

>> Now we want to replicate some schemas from the logical standby DB to a remote 11.2.0.3 DB.


I think you will be fine . . .

To Streams, the new "master" is just a database, and I see not reason why a database cannot accept logical standby while it also exists as a master, sending replication to another logical standby.


*****************************************
I'm not a Streams guru, but this fellow is:

http://www.rampant-books.com/book_0402_streams.htm

It's an outstanding book . . .

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>> restrictions for enable supplemental loggin (as needed by streams) on the logical standby.

http://www.dba-oracle.com/b_data_guard_logical_standby.htm

Since a logical standby database may not contain all the objects from the primary database, the switchover to the logical standby database may restrict the services offered by the true primary database. As a result, the DBA should carefully consider the objects to be replicated in a logical standby database during the configuration phase.

Here are all Streams restrictions:

http://docs.oracle.com/cd/B28359_01/server...estrictions.htm

All it notes is that LOB, LONG, LONG RAW, user-defined type, and Oracle-supplied type columns cannot be part of a supplemental log group.

[pkoehle]

Thank you very much, Mr. Burleson, especially for the unbelievable quick answers!

We will try it out this weekend - maybe the high management will have to wait for some reports on Monday - and I'll inform you (and the community) about the results.

BR, peter

best oracle site in this world: http://www.dba-oracle.com/

[burleson]

Hi Peter,

>> best oracle site in this world: http://www.dba-oracle.com/

Thanks for the kind words! I work very hard on my site, and I'm happy that you find it useful.

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>> I'll inform you (and the community) about the results

That would be wonderful!

I sent this note asking some of my experts:

http://www.dba-oracle.com/t_streams_logica...or_receiver.htm

Can a database act as a logical standby, and at the same time, send replication to another logical standby?

IOW, can any single database be both a sender and receiver of logical standby replication streams?

[pkoehle]

results from our tests last weekend:

First: it works!

Second: setting up streams has to be done very carefully: even a small little mistake can lead to big problems and a lot of time used for investigations - as the error messages are realy of very poor quality (eg different character sets lead to not working propagation without according messages ...).

To everyone who has to do similar work: much fun and stay tuned

BR, peter

[renzjr]

results from our tests last weekend:

First: it works!

Second: setting up streams has to be done very carefully: even a small little mistake can lead to big problems and a lot of time used for investigations - as the error messages are realy of very poor quality (eg different character sets lead to not working propagation without according messages ...).

To everyone who has to do similar work: much fun and stay tuned

BR, peter

I'm looking for this solutions, too. Thanks it works!

[SteveC]

For what it's worth, the architecture of downstream capture and logical standby are almost identical.

[pkoehle]

I have to apologize but it doesn't work

capture ist fine
apply seems to be fine
instantiation works

but propagation doesn't - now orcle support says it might be a bug in 10.2.0.5 (they are still investigating)

we did an upgrade of our logical standby to 11.1 => everything works fine now; easy to setup as described

so our configuration now is:

production on 10.2.0.5 HPUX => logical standby 11.1 HPUX => streams (due to endian differences between HPUX and RHEL) => new production 11.2.0.3 RHEL

[burleson]

Hi

You can manually move the redo logs with a shell script.

Just write a deamon process and wit for a new redo to appear,

when it's done, have the script trapsport it into the standby redo log drectory.

If you don't want to write your own, there might be one of these in the Oracle script collection:

http://www.dba-oracle.com/oracle_scripts.htm

Lastly, make Oracle Tach support provide you with a workaround!