Netlinx M2M Communications URL definition

RicardoSiqueira

In a 2 master system. Does it matter in which Master you define the URL Listing? I have a NXF fully loaded and a NI-4100 with less devices. I defined the URL of the 1st Master (NXF) on the 2nd (NI-4100). I know you can only define it on one Master... Would it matter or be better do do the opposite? Master 2 defined on Master 1? Any ideas?

John Nagy

It makes little difference from what we can tell, though we normally set the slave up to do the connection. That way, if the slave is offline, the master doesn't waste cycles trying endlessly to reach the slave. Probably more a conceptual load than a real issue, though. It will be interesting to see other opinions.

HARMAN_icraigie

I have found that planning out the routes and setting route mode direct can improve perceived and measured performance with large distributed logic systems - ie the slave controllers are doing more than just hosting communication modules. But usually it's the "slave" controller that hosts the URL listing.

DHawthorne

I had one time a master brought to it's knees because it had a lot going on and too many other masters in it's URL list. Though it ran like that for years, one small program change later, and it wouldn't boot. When I cleared its URL lists and moved them to the other masters, it recovered and worked just fine after, with no other changes.

So there is definitely some overhead, and it can be additive. My system that had issues has seven masters, and was definitely happier with all the connections being maintained on a distributed basis rather than being done by the master that had the most going on otherwise.

roognation

Agreed: route mode direct and slaves point at the master.