Jail-server instalation/configuration troubleshooting

Instalation

We recomend to use one of our preinstalled jail-servers and adapt it to your need. If you decide to install a jail-server you must notice two things:
1.    The 1.0.1 jail-server system version is only suitable (its script to manage the jail file system and the daemon) to Red-Hat, CentOS and other Red-Hat fully compatible linux distributions. In a near future it will be ready to be installed in Ubuntu.
2.    The daemon needs a C++ compiler to be built.

Configuration

1.    After installing the jail-system you can check the service with “service vpl-xmlrpc-jail restart”. If all is OK no error must be shown. The jail-system needs a NFS server running to prepare the jail file system replica.
2.    After installing the jail-server you can use a “telnet” to check that the server is accepting requests. Don’t forget to use the adequate port with ”telnet” (the port number is set at "/etc/xinetd.d/vpl-xmlrpc-jail", but may change with NAT configuration). The server should respond with an error message because it expects an http request. If no reply you may have a server configuration issue or firewall problem.
3.    Check that the URL you are using is according with the “-uri” parameter at "/etc/xinetd.d/vpl-xmlrpc-jail"
4.    If you need more information you can add "-d 255" in “server_args” at "/etc/xinetd.d/vpl-xmlrpc-jail" to get detailed information in the system log (jail-server).
5.    To check an activity you can use the next "vpl_evaluate.sh" file for C language.
---------begin of file--------------
#!/bin/sh
gcc -Wall -o vpl_execution *.c
----------end of file--------------
If the evaluation doesn’t work, you must check your resource limits.
6.    If the step 5 works, you can check console execution filling “vpl_run.sh” with the same code as "vpl_evaluate.sh" and pushing “run” button.  If this step fails you may have a firewall configuration issue on the moodle server. You need to open the range of ports you have set in the general configuration of the module.