10 Replies Latest reply: Jul 10, 2013 11:49 PM by 998712 RSS

    DATAGUARD OBSERVER DOUBT

    794625
      is it possible to configure more than one observer (dataguard) for particular primary and physical standby database?

      or some other options to protect observer? what else we have to do to protect/ unplanned shutdown of observer server machine?

      oracle version 11gR2 , operating system OEL 5

      Thanks and Regards,
      Rajesh
        • 1. Re: DATAGUARD OBSERVER DOUBT
          618702
          Dear 791622,

          Please see;

          http://www.trivadis.com/uploads/tx_cabagdownloadarea/te_dg_observer_doag-mnb2_02.pdf
          http://blogs.oracle.com/AlejandroVargas/gems/DataGuardBrokerandobserverst.pdf
          http://www.orafaq.com/wiki/Data_Guard_implementation_for_Oracle_10gR2#DATAGUARD_OBSERVER_:

          +"+
          +DATAGUARD OBSERVER :+

          +Observer is a utility that is available with the dataguard. Its basic purpose is to keep the database available to the clients all the time. It is started on a separate location other than Primary and Standby locations. After starting the observer, it starts watching continuously both the sites. Whenever the PRIMARY database fails due to any reason and the connection between the PRIMARY site and the observer breaks, the observer waits for a certain time which is set up during setting the broker configuration. When this time passes, the observer automatically starts the failover process. As a result, the Physical Standby database is converted to PRIMARY database. After this failover, the users again connect to the database. This connection redirects them automatically to the new PRIMARY database.+
          +"+

          As far as i know, there can be only one observer for a single data guard broker configuration with the fast start failover option. Protection of the observer client or the box can be achieved on system level.

          Regards.

          Ogan
          • 2. Re: DATAGUARD OBSERVER DOUBT
            794625
            Hi ogan,

            thanks for your fast reply,

            we already had 11gR1 active dataguard configuration setup.

            my question is , is it possible to configure more than one observer for particular primary and physical standby database?

            i also guess the same for one dataguard setup one observer.

            waiting for some others reply
            • 3. Re: DATAGUARD OBSERVER DOUBT
              618702
              791622,

              I have never read such documentation that describes installation of more than one observer to a single configuration.

              So one data guard configuration and one observer. Otherwise which one knows where to start the failover steps?

              May i ask you that why do you need such configuration? To protect the observer or create a backup (spare) observer?

              Regards.

              Ogan
              • 4. Re: DATAGUARD OBSERVER DOUBT
                Uwehesse-Oracle
                There can only one Observer be present to watch one Configuration.

                If you are on 11g and using Grid Control , you can specify an alternate Observer that is started if the first fails and can't get restarted.

                Kind regards
                Uwe Hesse

                http://uhesse.wordpress.com
                • 5. Re: DATAGUARD OBSERVER DOUBT
                  618702
                  Dear Uwe Hesse,

                  Thank you very much for the clarification.

                  Regards.

                  Ogan
                  • 6. Re: DATAGUARD OBSERVER DOUBT
                    618702
                    Dear 791622,

                    Please also check the online documentations;

                    http://download.oracle.com/docs/cd/B28359_01/server.111/b28295/gui.htm#DGBKR450
                    http://download.oracle.com/docs/cd/B28359_01/server.111/b28295/sofo.htm#BCGFFFHB

                    *"*
                    *There can be only one observer monitoring the broker configuration. If you attempt to start another one, the broker returns the following error message:*

                    *ORA-16647: could not start more than one observer*
                    *"*

                    Regards.

                    Ogan
                    • 7. Re: DATAGUARD OBSERVER DOUBT
                      794625
                      thank you very much ogan and Uwe Hesse for your kind response.

                      Regards,
                      Rajesh
                      • 8. Re: DATAGUARD OBSERVER DOUBT
                        Uwehesse-Oracle
                        You're welcome :-)
                        • 9. Re: DATAGUARD OBSERVER DOUBT
                          user3535662
                          How exactly can one define an alternate observer ? Couldn't find one,
                          • 10. Re: DATAGUARD OBSERVER DOUBT
                            998712

                            hi

                            can you upload some document or web link for how can i start alternative observer?