> Hi Stalin,> You are welcome! You have broached a very interesting subject which was> discussed very intently during our project. The long-term goal was to have> the Observer installed on an independent data center (C) different from the> PRIMARY (Data Center A) and HA (Data Center B). But Data Center C is not> yet available. In the interim, we will have the Observer running on A with> the option to run on B (if and when necessary) similar to an Failover> Cluster configuration. We have Hitachi True Copy replicating the all> important fsfo*.dat file (key to Observer startup) from A to B. This> replication is done in synchronous mode, such that if there is an Observer> failure on A, B has the accurate version/copy of the fsfo*.dat file for the> Observer startup. Again, this was done keeping in mind the customer's all> important requirement - Automation.>> This topic of Observer configuration and setup in itself can be a> discussion that can last many days :))) And there are different failure> scenarios that one needs to be understand, plan for and deal with. If you> have not already done so, I'd happily recommend that you read a> presentation by Martin Bracher from Trivadis (albeit from 2008 but still> very relevant). Martin has done an excellent job on the subject, kudos to> him!>> -> http://www.trivadis.com/uploads/tx_cabagdownloadarea/te_dg_observer_doag-mnb2.pdf>> Cheers,>> Gaja>>> Gaja Krishna Vaidyanatha,> CEO & Founder, DBPerfMan LLC> http://www.dbperfman.com> http://www.dbcloudman.com>> Phone - +1-650-743-6060> http://www.linkedin.com/in/gajakrishnavaidyanathaCo-author:OracleInsights:Tales of the Oak Table -> http://www.apress.com/book/bookDisplay.html?bID14> Co-author:Oracle Performance Tuning 101 -> http://www.amazon.com/gp/reader/0072131454/ref=sib_dp_pt/102-6130796-4625766> Enabling Cloud Deployment & Management for Oracle Databases>>> ________________________________> From: Stalin <stalinsk_at_gmail.com>> To: Gaja Krishna Vaidyanatha <gajav_at_yahoo.com>> Cc: Oracle-L List <oracle-l_at_freelists.org>> Sent: Wednesday, March 7, 2012 3:53 PM> Subject: Re: Active Dataguard -- Cascade Standby or not>>> Thanks Gaja for sharing us the experiences from your recent POC. I> appreciate it.>> Apparently our project ended-up with having only One ADG and One DR side> off of primary, similar to your setup except primary being RAC.>> Just curious on observer setup. Was observer installed on a separate site> different from primary and HA or monitored from primary always? How did you> establish HA for observer process as there can be only be one observer> monitoring the health of DG setup. Is this managed by GC.>> Thanks,> Stalin> --> http://www.freelists.org/webpage/oracle-l>>>