Hi, I have managed to set up JBoss servers before whitout any problem, but i am currently experiencing a few issues. 2 Servers recently had a fresh Fedora Core 5 install, and now i cannot get JBoss to start without errors (related to UDP multicasting). The current exception i get is: java.lang.Exception: dest=/233.3.3.21:45551 (52 bytes) | at org.jgroups.protocols.UDP._send(UDP.java:356) | at org.jgroups.protocols.UDP.sendToAllMembers(UDP.java:300) | at org.jgroups.protocols.TP.doSend(TP.java:938) | at org.jgroups.protocols.TP.send(TP.java:927) | at org.jgroups.protocols.TP.down(TP.java:716) | at org.jgroups.stack.DownHandler.run(Protocol.java:120) | Caused by: java.io.IOException: Network is unreachable | at java.net.PlainDatagramSocketImpl.send(Native Method) | at java.net.DatagramSocket.send(DatagramSocket.java:612) | at org.jgroups.protocols.UDP._send(UDP.java:330) | ... 5 more | 2006-11-07 14:52:03,091 ERROR [org.jgroups.protocols.UDP] failed sending message | java.lang.Exception: dest=/233.3.3.21:45551 (52 bytes) | at org.jgroups.protocols.UDP._send(UDP.java:356) | at org.jgroups.protocols.UDP.sendToAllMembers(UDP.java:300) | at org.jgroups.protocols.TP.doSend(TP.java:938) | at org.jgroups.protocols.TP.send(TP.java:927) | at org.jgroups.protocols.TP.down(TP.java:716) | at org.jgroups.stack.DownHandler.run(Protocol.java:120) | Caused by: java.io.IOException: Network is unreachable | at java.net.PlainDatagramSocketImpl.send(Native Method) | at java.net.DatagramSocket.send(DatagramSocket.java:612) | at org.jgroups.protocols.UDP._send(UDP.java:330) | ... 5 more I am pretty certain multicasting is enabled as i have the following entry in /sbin/ifconfig UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 I am using JBoss 4.0.4GA along with Java 1.5.0_08 Does anyone have an idea what is causing the problem ?? Thanks in advance, Andy View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3983772#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...