RE: Active Dataguard -- Cascade Standby or not

Date: Fri, 2 Dec 2011 04:51:34 +0000
Message-ID: <>

This sounds really cool- I am looking forward to your experience on this project.

-----Original Message-----

From: [] On Behalf Of Gaja Krishna Vaidyanatha Sent: Thursday, December 01, 2011 1:44 PM To:; oracle-l
Subject: Re: Active Dataguard -- Cascade Standby or not

Hi Stalin,
Currently doing an HA & DR PoC using ADG in the "Cascade Configuration" at a customer site. Conceptually, we are thinking pretty much on the same lines as you are and evaluating the use of the first "SYNC STANDBY" (if I may use that term), as the propagator to the other STANDBYs. This takes the additional overhead off the PRIMARY and imposes most of the propagation load on the SYNC STANDBY (reporting instance), yet optimizing the lag for the other STANDBYs. Will post the results when the PoC is complete and the results are available.



Gaja Krishna Vaidyanatha,
CEO & Founder, DBPerfMan LLC

Phone - +1-650-743-6060 Insights:Tales of the Oak Table - Co-author:Oracle Performance Tuning 101 -

 From: Stalin <>
To: oracle-l <> Sent: Wednesday, November 30, 2011 5:24 PM Subject: Active Dataguard -- Cascade Standby or not  

We have a requirement from one of our customer to have up to 15 ReadOnly DB sites all replicating data from so called primary site. Active dataguard seems to be a perfect fit but I was wondering the impact on the primary site in replicating data to all 15 readonly Active physical standbys. Only one standby site will be the failover target and configured in SYNC Availablity mode and rest in ASYNC Performance mode. Also, i was wondering if having a cascade standby's instead of having primary site to replicate all standby's a viable option to reduce load on primary with the trade off in additional lags from standby.
If anyone could share your experences or things to watch for in similar setup is greatly appreciated.



PS. RAC (Primary), (Standby, Single Instance), Linux


-- Received on Thu Dec 01 2011 - 22:51:34 CST

Original text of this message