I'm seeing this log recently, WARN [org.jboss.jms.server.connectionmanager.SimpleConnectionManager] A problem has been detected with the connection to remote client 4sl4g5w-feecev-fp1q2ikk-1-fp1qp6qk-1fe, jmsClientID=null. It is possible the client has exited without closing its connection(s) or the network has failed. All associated connection resources will be cleaned up. This log is from SimpleConnectionManager.cleanupForSessionID(String jmsSessionID), which is called when connection failure has been detected (see SimpleConnectionManager.handleConnectionException()). What is strange is that in this log the jmsClientID is null. Could it be possible? I traced the source code and found that this jmsClientID actually is the ID that represents a client's jvm, it should come from this class: public class JMSClientVMIdentifier { public static String instance = GUIDGenerator.generateGUID(); } So if I was right, the static instance will never be null. I also found this null log in the log files I got days ago when I'm investigating JBM-1456 (https://jira.jboss.org/jira/browse/JBMESSAGING-1456), but i didn't notice this until now. Although the case is a bit sophisticated but this is a simple point of impossibility! Did I miss something? I hope someone can shed some light. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4199777#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...