Oracle coherence "Unable to refresh sockets: ..." - caching

Question

i'm running coherence cache server and it throws the following error after showing the member set and the member list info. And i'm not sure what's up. :(
Here is the exception that I'm getting.
Stopping cluster due to unhandled exception: com.tangosol.net.messaging.ConnectionException: Unable to refresh sockets: [InboundUnicastUdpSocket{State=STATE_OPEN, address:port=191.193.1.127:8088}, MulticastUdpSocket{State=STATE_OPEN, address:port=196.194.184.13:50110, InterfaceAddress=175.143.1.127, TimeToLive=12}, TcpSocketAccepter{State=STATE_OPEN, ServerSocket=191.193.1.127:8088}]; last failed socket: MulticastUdpSocket{State=STATE_OPEN, address:port=172.194.144.93:50110, InterfaceAddress=191.193.1.127, TimeToLive=12}
at com.tangosol.coherence.component.net.Cluster$SocketManager.refreshSockets(Cluster.CDB:91)
at com.tangosol.coherence.component.net.Cluster$SocketManager$MulticastUdpSocket.onInterruptedIOException(Cluster.CDB:9)
at com.tangosol.coherence.component.net.socket.UdpSocket.receive(UdpSocket.CDB:33)
at com.tangosol.coherence.component.net.UdpPacket.receive(UdpPacket.CDB:4)
at com.tangosol.coherence.component.util.daemon.queueProcessor.packetProcessor.PacketListener.onNotify(PacketListener.CDB:19)
at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:42)
at java.lang.Thread.run(Unknown Source)
Caused by: java.net.SocketTimeoutException: Receive timed out
at java.net.PlainDatagramSocketImpl.receive0(Native Method)
at java.net.PlainDatagramSocketImpl.receive(Unknown Source)
at java.net.DatagramSocket.receive(Unknown Source)
at com.tangosol.coherence.component.net.socket.UdpSocket.receive(UdpSocket.CDB:20)
at com.tangosol.coherence.component.net.UdpPacket.receive(UdpPacket.CDB:4)
at com.tangosol.coherence.component.util.daemon.queueProcessor.packetProcessor.PacketListener.o nNotify(PacketListener.CDB:19)
at com.tangosol.coherence.component.util.Daemon.run(Daemon.CDB:42)
at java.lang.Thread.run(Unknown Source)
What could be the cause? And I'm interested to learn if there are tools, techniques by which coherence errors could be investigated and tackled. please share.
-Thanks in advance,
Rose

Answer 1

That seem to either be a problem with your network/firewall setup (see http://download.oracle.com/docs/cd/E15357_01/coh.360/e15723/tune_multigramtest.htm) or with the JDK version (some behave badly in this specific network usage - one working fine is 1.6.0_22).
As for general troubleshooting aspects see:
http://download.oracle.com/docs/cd/E15357_01/coh.360/e15723/tune_datagramtest.htm#CIHFAHFB
http://download.oracle.com/docs/cd/E15357_01/coh.360/e15723/tune_perftune.htm
http://download.oracle.com/docs/cd/E15357_01/coh.360/e15723/appendix_errormsgs.htm#sthref979