How often to have robots check in with hubs

Discussion created by keith_k on Sep 13, 2009
I am curious to find out how others configure robots when it comes to the hub check-in interval.  We currently configure the check-in to 5 minutes (I think the default is 15 but do not recall).  My understanding is that this means it would take a hub up to 7.5 minutes to detect a robot that went down.  We have been using 5 minutes from the start, and we have never had an issue with it.

I am thinking of writing a probe with the NSA that would do more extensive robot checks and would rely on the robot up/down information from the hub.  If I do this, it would be nice for the hub to detect down robots more quickly.  I was thinking of changing the check-in interval to 1-2 minutes, but I am nervous about how much load that could put on the hub.  The good news is that we have lots of hubs, so the robot-to-hub ratio is never too high.  (I think our highest is probably around 200 robots to a single hub or maybe a bit higher than that.)  I think the hub could handle this load, but I would not want to find out I am wrong the hard way.

What check-in interval are others using?  How many robots per hub?  Have you noticed any issues with different settings?