I recently unpaired and repaired the entire network so I could do it with no security this time. However, I completely forgot the rule of doing it closest first and working out. Instead, I went to 1 end of the house and worked my way a cross. Everything seems to be working decent enough, but some devices are taking rather stupid routes to the hub now. Its been a couple of days and they haven't changed. Will they eventually? Is there a way to force them to without unpairing again? Like can I power them all down and turn them on 1 at a time? Z-wave repair seems to have zero affect. These are all z-wave plus devices.
They'll fall in line and take what routes they feel are best.... I wouldn't worry too much about it. If things are functioning well, don't touch it. And of course check for ghosts!
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No ghosts, at least according to hubitat. If you could see radio waves tho, it would look like a pretty elaborate spider web in my house.
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I second that. It is "better" to add close to far, but as long as a device is able to connect and has a route to the hub it isn't catastrophic either way.
May be able to do a repair after adding all devices in those cases to re-optimize the routing anyway if there is any question.
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A Z-Wave device will use whatever route worked the last time-- without searching for a better one-- until it has failed after being retried several times. Unless the hub intervenes, there is no pro-active route optimization if the last tried route succeeds. In contrast, even when a Zigbee network is idle, all repeaters still keep exchanging link status information and track how well they hear each other. An idle Z-Wave device doesn't do that; it has to experience a message delivery failure first.
When that happens, it will try whatever the next-to-last working route was (each device can keep track of several, calculated and distributed by the hub, in nonvolatile memory so they're retained if power is lost). If that works, the device sticks on that route forever, even if sub-optimal, until it fails, then tries another remembered route.
Should all remembered routes fail, it will resort to use of explorer frames (which get forwarded by every repeater that hears them) trying to discover a new route. If that succeeds, that route becomes the new last working route. This last scenario is obviously not great (it saturates the mesh and hobbles the performance of any other device trying to use it); hence those multi-second transit times that are sometimes observed in poorly performing meshes.
Rinse, repeat all of the above until the hub intervenes, calculating and distributing better routes... pre-700 series Z-Wave devices didn't have the memory or compute power to make them capable of optimizing routes on their own (700-series devices have the resources, but still rely on the hub for calculated routes). Only the hub maintains a 'mesh-wide' view of neighbor adjacencies, and it will only update that view (and distribute optimzed routes) when requesting devices to report their current neighbors. That happens during a Z-Wave repair.
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So if I wanted to intervene by shutting off a switch so that another switch has to look for a new route, would that work?
Yup, could shut off a device another device routes through and then activate the end device at the device - that would force it to find a new route to the hub. Really anything the breaks the last working route will force the device to try and find a new one when it needs to send its next message.
But keep in mind the end device doesn't know the route is broken until it tries to send a message - that is why you need to activate the end device in the above scenario.
You could also just do a z-wave repair on the device, too, though.
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Might try that thanks. The z-wave repair never seems to change anything when I do it.
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In an ideal world devices would all be added starting at the closest working out as detailed in the article that's available somewhere on this site, then battery operated devices afterwards. For someone who installs a system in one hit, all devices at once, maybe that's achievable. I'd imagine however, that there are more users out there like me, who are growing their system over time.
At the start of this year I had about 6 Z Wave devices total, all at the perimeter of the house (shutter modules for curtains). Over the last year I've installed dimmer modules (into every light switch in the house), switch modules (to integrate existing external lights and security floodlights), some smart implant modules (Bed TV and Intruder Alarm), and about 6 smart outlets. I'm now at 40 Z Wave devices and all of those devices were added in no particular order - "I think I'll do that light next....."
I've learned in the last year not to try and make sense of Z Wave Routing (after my post "Z Wave routing defies all reason"). Devices will chop and change their route and at times it makes no sense, but if everything is working just forget about it. I find that after adding a device there seems to be an incremental improvement over a number of days.
Luckily I also learned on this forum early on that S0 is evil and so are ghost devices. I switched off S0 on everything following advice on this site and also learned from some very helpful forum members how to use a Z stick to include with no security and also remove ghost devices.
In summary I've added everything in a pretty random order but everything has sorted itself out nicely and is working well...........touch wood
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