mod_cluster causes "Packet is discarded" WARNs on JBoss and fails to join with Apache

Solution Verified - Updated -


  • After setting up mod_cluster, I'm seeing the following warnings on JBoss:

    WARN  [org.jgroups.protocols.UDP] (OOB-19, packet from has different version (9.1.20) from ours (2.6.19). Packet is discarded
  • JBoss is failing to successfully join with Apache through mod_cluster as well.


  • JBoss Enterprise Application Platform (EAP) 5
  • JBoss Enterprise Web Server (EWS)
    • Apache httpd
    • mod_cluster

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