6 Replies Latest reply: Oct 13, 2011 1:22 PM by Uwehesse-Oracle RSS

    Active Dataguard switchover puts new standby in real time query

    user275290
      Hi Gurus,

      If using Active Dataguard ,after swicthover/failover using dg broker and observer does sthe new standby will be put in real time query mode(ADG) or manually have to open the db in read only mode.

      Please let me know.

      Thanks
        • 1. Re: Active Dataguard switchover puts new standby in real time query
          CKPT
          If using Active Dataguard ,after swicthover/failover using dg broker and observer does sthe new standby will be put in real time query mode(ADG) or manually
          have to open the db in read only mode.

          AFAIK, database will be bounced and it would be in Mount & MRP will be started by broker, I dont think automatically database will be open(read only) .
          Lets have a try, not a big deal to open database.
          • 2. Re: Active Dataguard switchover puts new standby in real time query
            Uwehesse-Oracle
            Yes it does:
            [uhesse]$ dgmgrl sys/oracle@prima
            DGMGRL for Linux: Version 11.2.0.1.0 - Production
            
            Copyright (c) 2000, 2009, Oracle. All rights reserved.
            
            Welcome to DGMGRL, type "help" for information.
            Connected.
            DGMGRL> show configuration
            
            Configuration - myconf
            
              Protection Mode: MaxAvailability
              Databases:
                prima - Primary database
                logst - Logical standby database
                physt - Physical standby database
            
            Fast-Start Failover: DISABLED
            
            Configuration Status:
            SUCCESS
            
            DGMGRL> show database physt
            
            Database - physt
            
              Role:            PHYSICAL STANDBY
              Intended State:  APPLY-ON
              Transport Lag:   0 seconds
              Apply Lag:       0 seconds
              Real Time Query: ON
              Instance(s):
                physt
            
            Database Status:
            SUCCESS
            
            DGMGRL> switchover to physt;
            Performing switchover NOW, please wait...
            New primary database "physt" is opening...
            Operation requires shutdown of instance "prima" on database "prima"
            Shutting down instance "prima"...
            ORA-01109: database not open
            
            Database dismounted.
            ORACLE instance shut down.
            Operation requires startup of instance "prima" on database "prima"
            Starting instance "prima"...
            ORACLE instance started.
            Database mounted.
            Database opened.
            Switchover succeeded, new primary is "physt"
            DGMGRL> show configuration
            
            Configuration - myconf
            
              Protection Mode: MaxAvailability
              Databases:
                physt - Primary database
                prima - Physical standby database
                logst - Logical standby database
            
            Fast-Start Failover: DISABLED
            
            Configuration Status:
            SUCCESS
            
            DGMGRL> show database prima
            
            Database - prima
            
              Role:            PHYSICAL STANDBY
              Intended State:  APPLY-ON
              Transport Lag:   0 seconds
              Apply Lag:       0 seconds
              Real Time Query: ON
              Instance(s):
                prima
            
            Database Status:
            SUCCESS
            Kind regards
            Uwe Hesse

            http://uhesse.wordpress.com
            • 3. Re: Active Dataguard switchover puts new standby in real time query
              CKPT
              @uwe

              Thanks, Can you clear me one more thing,

              What is the status of database before performing switchover. Is it mounted or open?

              After performing switchover, looks it is in sync. But OP asked do we need to open database for read only purpose after performing swithover Or automatically it will be in open?


              Thanks.
              • 5. Re: Active Dataguard switchover puts new standby in real time query
                Uwehesse-Oracle
                You can tell by the line

                Real-Time Query: On

                that the Physical Standby is READ ONLY OPEN WITH APPLY (offering Real-Time Query, in other words) in both cases (before & after the switchover)

                Q.E.D. :-)

                Kind regards
                Uwe Hesse

                http://uhesse.wordpress.com