7 Replies Latest reply on Mar 3, 2014 6:53 AM by T.F.-Oracle

    Stop application under cluster for maintenance

    ra*326096*ul


      Hi

       

      I  have a application which is under control of  the  cluster  and needs to be shutdown and startup manually for  maintenance like patching , how can I shutdown the application without it  causing the  resource group to switch over and start the application on another node and after  the  maintenance is   successful pass the control  back to the cluster

       

      TIA

        • 1. Re: Stop application under cluster for maintenance
          Juergens-Oracle

          Hi,

          you can simply do a ‘clrs disable application-rs’. With this command the application will be stopped and stay offline.

          Now you can do your maintenance. Which means you can start your application manually without cluster control. When you have finished your maintenance stop your application manually.

          Then start up the application again with cluster control by using ‘clrs enable application-rs’.

           

           

          Hth,

            Juergen

          • 2. Re: Stop application under cluster for maintenance
            ra*326096*ul

            Hi Juergen  Thanks for the reply

             

            Can  unmonitoring the resource  be used as well.  Just  wanted  to get clarity on   what is the difference between  disabling a resource /unmonitoring a resource/offlining a resource
            As per my understanding unmonitoring a resource will keep the resource  running but  will not be monitored by the cluster and then can  be  manually stopped and started till the monitor is turned back on again

             

            Thanks

            • 3. Re: Stop application under cluster for maintenance
              Juergens-Oracle

              Hi,

               

               

              yes, ‘clrs unmonitor’ and ‘clrs monitor’ is another option. In this case only the monitor for the resource will be stopped. This can also be enough to do the maintenance. But if somebody switchover/failover the resource group which include the unmonitored resource then the resource will also switch to the other node. So, it depends on your maintenance and what you expect.

               

               

              Hth,

                Juergen

              1 person found this helpful
              • 4. Re: Stop application under cluster for maintenance
                ra*326096*ul

                HI Juergen

                 

                I tried to  clresource unmonitor  <resource >

                THe resource in this case is a DB

                But  shutting down the DB it was again getting started

                Any idea why should that be  and what  should  be done that the DB can be shutdiwn manually

                 

                Thanks

                • 5. Re: Stop application under cluster for maintenance
                  T.F.-Oracle

                  Hi,

                   

                  when doing planned maintenance (like applying a patch or upgrading the application software) for an application under cluster control, the safest way is to:

                  • disable the cluster resource (clrs disable <resourcename>)
                  • perform the maintenance
                  • verify everything is working as expected
                  • enable the cluster resource again (clrs enable <resourcename>)

                   

                  There is also the possibility to suspend the whole resource group, where the application resource is configured in, by doing a "clrg suspend <resourcegroupname".

                  Then the cluster framework will not try to restart this resource group or trigger failover for it.

                  The resource group can be resumed by "clrg resume <resourcegroupname>".

                   

                  But here it really depends on the scope of change you apply to an application, if the data service monitor for the application resource can really continue to perform monitoring as before.

                   

                  In some cases the data service monitor is not only probe based, but does also perform PMF based monitoring, ie. it monitors the specific process ids (pids) that got started by its start method.

                  If you then manually stop the application, PMF might no longer see any of those pids, and thus determine a failed resource.

                   

                  That is why in general for performing maintenance on an application, you should start with disabling the resource. And enable it back once the maintenance is finished.

                   

                  Regards

                               Thorsten

                  • 6. Re: Stop application under cluster for maintenance
                    ra*326096*ul

                    Hi THorsten

                     

                    Thanks for teh detailed  reply

                    I have  disabled a resource with clrs disable resource

                    Now the status for the resource  is showing offline on both nodes

                    If I enable  the resource now where will it start the application running under this resource  and show online as the application running under the resource  has to come up on the same node   where the other resources for this application are running

                     

                    Thanks

                    • 7. Re: Stop application under cluster for maintenance
                      T.F.-Oracle

                      Hi,

                       

                      If you just disabled the specific application resource, and left other resources enabled and the corresponding resource group online, then if you enable the application resource, it will be started on the node where the resource group is currently online.

                       

                      It is always the resource group that will determine where the resources configured for this resource group switch online.

                       

                      Regards

                                   Thorsten

                      1 person found this helpful