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tanislavm's avatar
tanislavm
Level 6
10 years ago

global vcs

hi, if i have node a and b in site 1 and node c and d in site 2,then if i wish to configure them into global vcs in this way-nod a and node c serve a failover group and node b and d serve a parall...
  • mikebounds's avatar
    10 years ago

    You cannot add a system in another globally connected cluster to the SystemList - you have to use ClusterList and ClusterList  does NOTcontain systems, it contains clusters.

    The ClusterList is what makes a service group a "global service group" and if you create a global service group in the GUI using the wizard, then both clusters must be up and running, but you can manually edit ClusterList if the second cluster is not available (or if the wizard fails).  If you configure a global service group, then VCS prevents that group running on both nodes at the same time.  So if you want a parallel group across sites, then simply don't configure it as a global group.

    So for example you can create cluster 1 as follows:

    group failoversg (
      SystemList = { nodeA = 0 }
      ClusterList = { clus1 = 0, clus2 = 1 }
    
    group parallelsg (
      SystemList = { nodeB = 0 }

     

    This means locally each service cannot failover, but failoversg can fail across sites (nothing in cluster 1 that defines which nodes it fails to, just that it fails to clus2) and parallelsg cannot fail across sites.

    So then cluster 2 would look like:

    group failoversg (
      SystemList = { nodeC = 0 }
      ClusterList = { clus1 = 0, clus2 = 1 }
    
    group parallelsg (
      SystemList = { nodeD = 0 }

     

    So here it is defined that global group failoversg can failover to nodeC only (nodeD is NOT in SystemList) and as parallelsg is NOT a global service group (no ClusterList attribute), then it will online on both clusters.

    You can define local failover (and parallel) attributes for local clusters so cluster 1 could be defined like:

    group failoversg (
      SystemList = { nodeA = 0, nodeB = 1 }
      ClusterList = { clus1 = 0, clus2 = 1 }
    
    group parallelsg (
      SystemList = { nodeA = 0, nodeB = 1 }
      Parallel = 1
    

     and likewise you can do the same for cluster 2

     

    Mike