4 Replies Latest reply: Jul 5, 2009 11:21 PM by 693987 RSS

    RAC DB Start/Stop with Dataguard and FSFO

    693987
      Hi there,

      Quick question for those well versed w/DG Broker. We have a 3 node primary and 3 node standby RAC/DG/FSFO setup running on Suse Linux, 10204. A bit of confusion has arisen from the ORA-16649 error (database will open after Data Guard broker has evaluated Fast-Start Failover status) and a team member has questioned the sequence of stop/start operations.

      Looking at the documentation (http://download.oracle.com/docs/cd/B19306_01/server.102/b14230/sofo.htm#BCGEFICG) we see comments indicating certain client tools can't be used to open a database. Unfortunately, that doco doesn't clearly expose the acceptable methods of stop/start a RAC DB in a FSFO config.

      so basic question is do we use standard srvctl start database ... srvctl stop database ... etc. Are there particular "operational" rules/guidelines exposing best and/or standard practice in this manner.

      I believe i've searched doco reasonably well but realise i could have missed something. Don't have much experience w/the broker/DMON setup and my team "expert" is out of the office for 3 weeks (he knows the answer I am sure of it!). but for now - i need to assist a more junior team member understanding standard operating practice w/this config.

      Any thoughts, comments, documentation links, etc would be greatly appreciated.

      Regards
        • 1. Re: RAC DB Start/Stop with Dataguard and FSFO
          damorgan
          If you have a RAC cluster you must, for all practical purposes, uses Data Guard Broker.

          Once you use the Broker you must, for all practical purposes, ONLY use the Broker.

          Starting and stopping with any other tool will put the database out of synch. with the broker files and it is painful to rectify.

          So the answer to "can you?" is "yes." The answer to "should you? " is "only if you enjoy pain."
          • 2. Re: RAC DB Start/Stop with Dataguard and FSFO
            693987
            Thx very much for the response.

            that is how i understood it (though didn't articulate as well as i could have). the problem i have is i couldn't easily locate documentation outlining this requirement as a point of reference. we go to great lengths w/our documentation here and either i am simply not looking in the right spot or too many years as a PHB of DBAs and not a DBA myself is limiting my vision/interpretation. clearly we've missed detail on operational procedure (the dba asking the questions is in our test team) and unfortunately the guy who has been focused on this config for 9mths has had a sudden family issue - so haven't had a shadow working w/him to ensure knowledge transfer. my fault there ... :(

            whatever the case, i would like to back your comments w/documentation references - if any exist! some links below simply don't expose the issues created when using the broker in a FSFO config (or even the broker itself). the 11g reference below is further confusing indicating you can shutdown the db using sqlplus or dgmgrl ... which directly contradicts this http://download.oracle.com/docs/cd/B19306_01/server.102/b14230/sofo.htm#BCGEFICG

            i've been working w/oracle long enough to know documentation gaps are not uncommon so am not altogether surprised but am frustrated. w/out appropriate references we're stuck w/trial an error to nail down procedure. be that the case, no problem - just want to ensure we're not missing something.

            Links:
            http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/rac_support.htm#i641721 (Dataguard and RAC)
            http://youngcow.net/doc/oracle10g/server.102/b14230/cli.htm#i1005869 (DG Broker Performing Routine Maintenance Tasks)
            http://download-uk.oracle.com/docs/cd/B28359_01/server.111/b28295/deprecated_appx.htm#sthref1463 (11g doc ref footnote indicating you can shutdown w/sqlplus)

            any and all further feedback much appreciated
            • 3. Re: RAC DB Start/Stop with Dataguard and FSFO
              damorgan
              It is Sunday evening and I am about 10 minutes from dinner with the family so I am not going to have a chance to get to those references.

              What I can tell you is that my understanding and experience comes from meetings with members of Oracle's HA team, from personal experience (that equates to making mistakes), opening SRs at metalink (see "making mistakes"), and teaching Data Guard classes for several years.

              To be honest with you I am not sure it is all that well documented or I suspect I'd have made far fewer mistakes over the years.

              You might want to hit metalink. You might find some of my, and other's, painful mistakes to learn from. <g>
              • 4. Re: RAC DB Start/Stop with Dataguard and FSFO
                693987
                no worries at all - your responses confirm what i probably should have known!! have no issue w/making mistakes to learn and we've got the environments to do just that (the questions are coming from a e2e test env build procedure).

                i did hit metalink but probably got the search string wrong.

                maybe a direct question is helpful:

                - you can shut down a RAC database via DGMGRL> shutdown (and likewise startup)
                - but you can't do the same for an instance
                - so if you're doing node maintenance, you have to shut the instance w/srvctl ... rather than DG

                to be honest, i think that's about the gist of things. we've got no confusion around the broker config mgmt/properties, just this seemingly obtuse gap in the documentation.

                were we in washington, you'd have my team in the course mate, no doubt. :D

                thx again, if you have a sec to provide pointers, i'll chase them up.

                regards