We are in the process of installing MonLink – a script by author Ken Adkisson (WB4FAY) in Birmingham, Alabama. Ken and I had a wonderful discussion on his existing and new products while we were both at the Dayton Hamfest – he is definitely a mover-and-shaker in terms of writing D-Star Gateway utilities for Control Operators. I am deeply grateful to Ken for sharing his code with us and helping to make the process of managing and maintaing our systems easier, more effective and more consistent. MonLink was installed on our system on Friday, 04-June-2010. The details of MonLink are below, but in summary – MonLink constantly monitors our D-Star Gateway Links and restores them to “known states” after programmable durations of inactivity (like when somebody forgets to UNLINK). Future versions will also allow for extensive Link Scheduling for Nets, as well as automatic recognition of changes in Net schedules or Reflector changes.
    Following is the information provided by Ken to System Owners/Operators:
    • MonLink runs as a service on the D•STAR gateway.
    • It reads the ‘dplus.log’ file as input and actively monitors and manages the remote link connections.
    • If a link is established and remains inactive for a configurable amount of time, it is automatically disconnected.
    • There are separate configurable time values for input over the link and for local transmissions sent out on the link.    Therefore if the far end of the link has a lot of activity but nothing locally, it can still be disconnected in a specific amount of time.
    • If a link is established but is dropped by dplus due to repeated timeouts of the keep•alive pings, then MonLink will (if configured to do so) automatically try to reconnect the link.  The first attempt will be made 10 seconds after the failure.  Subsequent attempts will be made at 60 second intervals up to the maximum number set in the configuration file.
    • If a link is established, a recorded announcement will be played at a specific configurable interval to notify the users that a link is up and ALSO what system is on the other end.  For example, the announcement might say “Linked to REF001 module C”.  These announcements are ‘friendly’ in that they will only be played if the module has been quiet for a minimum of 30 seconds.

    Because MonLink is tracking channel activity, it also provides the ability to configure “general announcements” to be played on specified days, times, and modules.   Multiple messages can be defined and they will be played in rotation.  These announcements are managed as follows:

    The channel must have been:
    • quiet for the preceding 60 seconds, and
    • No other “general announcement” has been played for the preceding 10 minutes, and
    • This particular announcement has not been played for the preceding 60 minutes.
    • Times can be blocked out for any “general announcements” (e.g. during SE WX Net, etc.)