I had two xsam servers XSAM1&XSAM2 running in a cluster. When we stopped XSAM2 and tried to restart, It was getting stuck after printing "GSM Port ..." message. I tried to restart 2-3 time but couldn't. When we stopped XSAM1 also and restarted both XSAM1&XSAM2 then only both server got started successfully. As per my observation one jboss instance in cluster is blocking other one in some specific condition. This might be some jboss configuration issue but we need to simulate and fix it permanently so that it should not create problem next time.