Troubleshooting

Tips for troubleshooting issues that you may encounter when installing or running a Linux N4Supervisor:
  • error while loading shared libraries

    This error can happen with any of shared libraries in NiagaraAX: libnre.so, libplatform.so, or libjvm.so. Although these libraries are probably installed on your machine, the shared library loader cannot locate them. This mostly likely means you have not sourced the script '.niagara'.

    As user root, from your installation’s /bin directory, type the following:root@<host>:/opt/Niagara/Niagara-3.8.n/bin# . ./.niagara

    Then try whatever command you used to produce this error again (wb, nre, niagarad, station).

  • java.net.BindException

    This error can happen when starting a station. In the Linux OS, ports 1-1024 are “root ports,” meaning only an application running with root privileges may bind to them. Since 'station' is running as the user 'niagara' (who does not have root privileges), it cannot bind to port 80. If you have not configured your station to start on a port above 1024, you will see this error.

    To fix this error, configure your station to start its WebService bound to port 8080, or another port above 1024.

     NOTE: In N4.2, the Linux Supervisor station template is provided which creates a new station with the WebService already configured for HTTP on port 8080 and HTTPS on port 8443. You will still need to setup firewall rules to redirect port 80 to 8080, and port 443 to 8443. 
  • too many files open exception

    Large Supervisor stations typically require more file descriptors than the default number set for most distributions. The situation may occur where you have many concurrently open files (histories, alarms, etc.) which causes the exception, “Too many files open”. This simply means the file descriptor (FD) limit is set too low. Use means available to increase the limit to a greater value.