JavaParty FAQ

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Multicast configuration

If your runtime manager crashes with a java.lang.InternalError: config server crashed: java.net.SocketException: error setting options, something is wrong with your kernel routing tables. Make sure you have set a default route. For example on Linux you can check your routing tables with the following command:

> /sbin/route 
Kernel IP routing table
Destination  Gateway   Genmask       Flags Metric Ref Use Iface
129.13.0.0   *         255.255.0.0   U     0      0     0 eth0
loopback     *         255.0.0.0     U     0      0     0 lo
default      iracs1    0.0.0.0       UG    0      0     0 eth0

If the last entry is missing, you can not send and receive multicasts. If you can not fix this problem, you can try to start the runtime environment by manually setting host and port ouf your environment with arguments to the JavaParty commands:

1. Start the runtime manager on host <myhost>

jprm -host <myhost> -port 1099

2. Try to attach some virtual machines to the runtime manager

jpvm -host <myhost> -port 1099
jpvm -host <myhost> -port 1099
jpvm -host <myhost> -port 1099

Note: The default port for object export in KaRMI is 1099. To change this value, it is not enough to specify another value on the command line, because KaRMI expects all used ports to be declared in its configuration file. If you use JavaParty for RMI, you can freely choose a port, but then you must also specify it when invoking jprm.

3. Now start your application by also specifying host and port in the manner described above.

jp -host <myhost> -port 1099  <myclass>

Looking for the generated code

If you cannot find class Xxx_instance_impl (that might show up in a stack trace from our program), make sure, you specify the output directory for generated code, when compiling your program. See JavaParty/Commands.