I'm seeing the same behavior with a 37MB ear, JBoss 5.10 GA, and the base setup for clustering/JGroups (the All configuration). I am deploying using the recommended method of dropping the file into the farm directory on the master node. When I do this I begin seeing the "Cannot acquire local lock" messages on the child node. ~20 minutes later the deployment proceeds on both machines at the same time. I'm experimenting with changing the OS level UDP settings as suggested but have not had dramatically better results yet. I am raising the net.core.rmem_max limit and gathering deployment times to see if it is improving as I raise it however I stopped setting Udp packet receive errors once I took the limit above 2MB so I suspect something else may be limiting the file transfer now. I also don't see this behavior if I deploy to the master node while it is the only node and then bring up other nodes in the cluster after the deployment...i.e. when I do that the deployment to the child nodes is almost instantaneous following the typical startup time. This makes me thing the problem is not at the OS level. I'll zip and email my server log as well after turning on the logging and will post some timings from my deployment testing for others to compare against. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4243273#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...