3 Replies Latest reply on Apr 10, 2006 8:14 AM by Brian Stansberry

    Adding a GUID to JGroups Views

    Brian Stansberry Master

      Wanted to float the idea of adding a "cluster instance id" to JGroups views.

      This relates to http://jira.jboss.com/jira/browse/JBAS-1476
      and the related discussion at
      http://www.jboss.com/index.html?module=bb&op=viewtopic&t=73652 . In that thread, we've determined that adding a discovery mechanism to client proxies is a more robust solution than including a cluster instance id.

      However, I still think having the ability to identify a cluster instance has merit and could be useful. If breaking serializable compatibility is allowable in JG 2.3, this might be a good time to introduce such a thing in JG.

      A simple approach would be to create a java.rmi.dgc.VMID when a ClientGmsImpl converts to a CoordGmsImpl. Thereafter, that VMID is passed around as part of the view no matter who the coordinator is.

      Related to the JBAS-1476 discussion, the current viewId passed back and forth between clustering clients and the server is a hash of JGroups IpAddresses. If we had a cluster instance id, we could include that in the hash function. Not necessarily any need to propagate it separately, meaning no API changes needed.