2 Replies Latest reply on Jun 13, 2012 3:41 PM by ilocatelli2

    Clustering question




      I'm working with different implementations of active clustering (share nothing or share datastore).


      Configuration is not giving problems and apparently clustering is working fine even with some unexpected shutdowns on slave or master.


      My question is: how can i be *really really* sure that contents on master are exactly the same to contents on slave? it should be the most simple question.


      I expect CQ to alert me if repositories are not aligned. A single misalignment on a node attribute may result in a *big problem* with user navigation.


      Unfortunately I experienced different situations where contents on master and slave were not aligned. For any possible reason, even related to errors or system problems on an instance.

      I cannot pretend that misalignments do not happen... but I would like to be informed when repositories are not aligned. How can I trust the cluster if both CQ instances are working fine without errors but repositories are different? Are there tools / alerts / best practices that can make me absolutely confident that 2 repositories are exactly the same? If I cannot be certain about this point, how a cluster can be of help?


      Hope someone may help me solve this problem that today makes me not confident in using a clustered solution.





        • 1. Re: Clustering question
          Ryan Lunka Level 3

          Have you looked at the Repository Check?  It's a diagnostic tool at http://localhost:4502/crx/config/check.jsp that is supposed to identify inconsistencies in the cluster nodes and (if selected) fix them.  I would start here and see how this suits your needs.  Here's a good Knowledge Base article that discusses this issue as well: http://dev.day.com/content/kb/home/Crx/Troubleshooting/RepositoryInconsistency.html.  Hope this helps!

          • 2. Re: Clustering question
            ilocatelli2 Level 1

            Hi Ryan


            Thanks for your answer, but it's not related to what I'm asking.

            I'm not concerned about repository inconsistencies (that are well documented by error logs) but of the possible not-alignment in two cluster node repositories. Individually both repository nodes are consistent, but so far I cannot be *really* sure both repositories have exactly the same content... and indeed my master and slave instances have different contents .... and nothing in the cluster is alerting me about this.


            So my question is very simple: how can I trust the cluster if contents may differ in time and nothing tells me that it is happening??? I would like the cluster to advice me that there is an out of synch situation, but so far I don't understand when an out of synch is raised... and above all in this moment I see different contents without any error / alert.


            I think this question should have an answer in order to consider CQ cluster a robust solution. If my question is not appropriate or if I'm misunderstanding something, I would be glad to everyone showing me where I'm wrong or where I can have a better solution / configuration. I suppose CQ/CRX clustering is used in many production environments, so I would be very interested in other opinions.