[jbosscache-issues] [JBoss JIRA] Created: (JBCACHE-1549) Buddy pool tracking when 2nd to last member leaves group

[Brian Stansberry (JIRA)]

Buddy pool tracking when 2nd to last member leaves group
--------------------------------------------------------

                 Key: JBCACHE-1549
                 URL: https://jira.jboss.org/jira/browse/JBCACHE-1549
             Project: JBoss Cache
          Issue Type: Bug
      Security Level: Public (Everyone can see)
          Components: Buddy Replication
    Affects Versions: 3.2.1.GA
            Reporter: Brian Stansberry
            Assignee: Manik Surtani
            Priority: Critical


If you have a 2 node cluster with buddy replication, and you restart one node, that node does not receive a state transfer. See forum thread for details of the exact symptoms.

Problem is this in BuddyManager$AsyncViewHandlerThread.handleEnqueuedViewChange():

         // there is a strange case where JGroups issues view changes and just includes self in new views, and then
         // quickly corrects it.  Happens intermittently on some unit tests.  If this is such a case, please ignore.
         if (members.newMembers.size() == 1 && members.newMembers.get(0).equals(cache.getLocalAddress()))
         {
            log.info("Ignoring membership change event since it only contains self.");
            return;
         }

Problem is the if condition is always true when the 2nd to last member leaves the group, but returning leaves the last member in a state where it thinks the next to last member is still a buddy. When that node restarts and rejoins the group, the reassign buddies logic sees that the new member is already a buddy and returns without pushing state.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira