3 Replies Latest reply: Oct 25, 2012 2:19 AM by JohnWatson RSS

    What happens if by mistake physical standby is opened?

    User447797-OC
      Oracle RDBMS : 11.2.0.2 RAC on RHEL 5.6 with ASM,OMF

      what will happen if physical standby database is opened when in standby role plus primary is opened? And what do we need to do to get back the data guard configuration?
        • 1. Re: What happens if by mistake physical standby is opened?
          mseberg
          Hello;

          Have tested. Nothing. It will probably bark because its in Recovery mode.

          But you need to do a shutdown, then a startup mount and the start apply again.

          Todays test
          /home/oracle:STANDBY >sqlplus " / as sysdba"
          
          SQL*Plus: Release 11.2.0.2.0 Production on Wed Oct 24 16:04:54 2012
          
          Copyright (c) 1982, 2010, Oracle.  All rights reserved.
          
          
          Connected to:
          Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
          With the Partitioning, OLAP, Data Mining and Real Application Testing options
          
          SQL> alter database open;
          alter database open
          *
          ERROR at line 1:
          ORA-10456: cannot open standby database; media recovery session may be in
          progress
          
          
          SQL> 
          So no action is required if you do this ( above ). If you shutdown apply and open it then you need to shutdown and restart mount and restart apply.

          A good example is active Data Guard :

          http://juliandyke.wordpress.com/2010/10/14/oracle-11gr2-active-data-guard/

          Best Regards

          mseberg

          Edited by: mseberg on Oct 24, 2012 4:10 PM
          • 2. Re: What happens if by mistake physical standby is opened?
            abdul:
            951368,
            what will happen if physical standby database is opened when in standby role plus primary is opened?>

            well,It will not open your standby until you dont run the command like "alter database recover managed standby database cancel;"

            and if he/she cancelling the log apply obviously standby will no more in receiving apply logs .
            what do we need to do to get back the data guard configuration?
            ,we need to just much neither need to shut down the db ,run the below command only:
            alter database recover managed standby database using current logfile disconnect ;
            or
            alter database recover managed standby database disconnect ;
            • 3. Re: What happens if by mistake physical standby is opened?
              JohnWatson
              The standby will open read only (see v$database.open_mode.) Redo will continue to be recieved but will not be applied (see the transport lag and apply lag in v$dataguard_stats). If you then start redo apply, you will be enabling Active Data Guard Real Time Query, which does require a separate licence.