4 Replies Latest reply on Feb 13, 2015 5:16 AM by Radoslav Husar

    mod_cluster and new nodes

    Casey Lee Newbie

      Using mod_cluster 1.2.1 in front of JBoss AS 7.1 servers.  We use busyness for the load metric.  A challenge that we are seeing is that when new nodes are added to a busy cluster the node receives a majority of the traffic for a few minutes, i assume because his elected numbers are low and his load is high.  Problem is however that often times this causes a DOS of that box and sometimes brings the JBoss server down.  As a result we've had to make a practice of adding many servers at once to limit this impact.

       

      Couple questions...first, any suggestions on ways to avoid this?  Additionally, it seems that the busyness metric calculates usage across all pools (HTTP and AJP).  Since we only use AJP, this returns false load numbers that never go below 50.

       

      Thoughts appreciated!

      -Casey