Zigbee issues on C8

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I need help! I think I have multiple issues at play and I need an idea regarding what steps I could take to fix my Zigbee issue on C8. First, my C7 hub was not centrally located in my house but I've never had problems until I added an external zwave (S2) Alfred lock on the opposite side of my house from the hub. Performance was horrible. 23 hops to get from hub to lock. I moved my C7 hub to a more central location. Additionally, I upgraded from version 2.3.7.139 to 2.3.7.145. Now the problems start.

The ZigBee radio kept dropping my devices intermittently on the C7. That's never happened before. It's always been very stable. I decided to use cloud migration tool to migrate from C7 to C8 to see if that solved my problem. Instead of fixing the problem, it made it far worse. My devices would connect to the C8 Zigbee radio, but they never communicate again. There would be no pings and no reading of the device's from the hub. Everything else was working fine. Love the range of the new zwave radio! Anyway, I tried adding a device to my SmartThings station to see if the 2 Zigbee radios were interfering with each other. The device in question which is a temperature sensor worked perfectly on the SmartThings station.

To make my ZigBee devices work I moved my C7 hub to its previous location created a hub mesh and then disabled everything on C7 except for ZigBee devices. I disabled the C8 radio. That seems to be working fine. But I don't really want to maintain two hubs as I only have about 30 devices total.

One thing confusing is when I run the scan under Zigbee details
on C7 I see the Pan ID of my C7 hub. When I run the scan under Zigbee details for the C8 hub I never see the pan ID listed in that hub's scan results. This was before I plugged C7 back in and disabled C8 Zigbee radio.

That's a lot of info but any idea's how to get everything working on C8 hub only?

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One general comment - the Zigbee scan is not 100% reliable - a number of us have gotten results that seem inconsistent, so while it can be useful, it can also sometimes be confusing.

Regarding potential Zigbee radio interference, which could be a part of your issues.

  1. Note the current channel selections for each Hubitat hub on their Zigbee Details page. Also get this info for your SmartThings hub if you're also running Zigbee on it as well. Make sure each HE hub and SmartThings are on different Zigbee channels.
    -- NOTE: Unless you need your SmartThings station on and running Zigbee you should power it off, the more Zigbee radios you have running, the more likely you could have interference.

  2. Use the info below to check for potential Zigbee radio interference w/your (and neighbors) 2.4GHz Wi-fi. The mobile app WiFiMan (from Unifi, iOS and Android versions) is a good tool to use to see radio congestion in your home. Ideally you have your 2.4GHz on the low end of the spectrum and if you have two Zigbee radios on, you can put them on 20 and 25. After a Zigbee radio channel change it can take a few hours for all of the Zigbee devices to reconnnect.

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Your problems may have started due to moving the C7 to a new location - that may have resulted in it being in a location where your original mesh connections were no longer optimal and performance would suffer. Both your Zigbee and Z-Wave mesh connections are optimized based on device location/connection strength to other devices in the mesh and ultimately the hub. When you moved your C7 to a different/central location at least some the devices on your hub would likely need to find new optimized connections.

You can "hurry" this along for Zibee by forcing a Zigbee Panic (turn off and unplug C7 20m and then plug in/start up again). The "panic" gets each of your Zigbee devices to rebuild their neighbor tables and find new optimized routes to the hub. On the Z-Wave side there isn't as easy a path to hurry this process, you can try doing a general Z-Wave repair but it can still take days - devices should work but might not fill in routes .

If you migrated quickly to the C8 at that point AFAIK (could be wrong) you'd migrate the Zigbee routes as well (Z-Wave gets cleared) and so that may have just moved your troubles to the C8.

You may be able to move your Zigbee devices back to your C8 after you ensure your hubs aren't fighting w/each other or Wi-Fi for signal space.

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I understand your problem is now with Zigbee however, I had a similar experience when I added a second Alfred lock (I have very few Z-Wave devices, 4 or 5) but instead of moving the hub I bought a Zooz ZAC38, plugged it in near the new lock and that was that. The ZAC38 has no problem talking directly with the hub (and the lock).

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In order to have a good experience post migration, you must ensure that pre-migration mesh is healthy. If you have devices misbehaving on C7, the problems will likely follow you to the new hub in oftentimes the shift to a new controller makes things worse.

Moving part of the hub back to C7 made things more difficult to bring everything together. Your option now is move everything back to C7, run another cloud backup and perform the migration again, or manually bring back your Zigbee devices to the C8. Not sure what you have left on the C8 and which effort will be greater for you.

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On the cloud c8 migration it says "Rebuild the database" What does that entail? Can you give me a high level definition? Don't need details. I don't want bury myself even further. Thanks for responding.

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Thanks for the tip. I'll give that a shot.

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I did not know this.

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Don't want them banging on each other unnecessarily. :slight_smile:

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Ok, now, I'm really getting confused. The C7 channel scan shows my zigbee network on channel19. The pan id's match. My SmartThings station says it's on channel 19 but the PanID does not match the Pan ID for the ST Station. There are 2 Zigbee networks on channel 19. The C7 zigbee details says it's on channel 20. I have an echo studio which has a Zigbee hub built in. Can't figure out how to find its Pan ID. Sometimes a third zigbee network shows up on channel 25 but not every scan. Thoughts? Any other zigbee network analyzers out there?

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Don't use the Zigbee channel scans...look up the channel setting on each device so you can be sure.

The Settings>Zigbee Details screen for HE, and I don't remember where for SmartTHings but there should be a way to look up its Zigbee channel setting on it as well.

Then combine that info w/a look at your local Wi-Fi channels using the Unifi app. If Wi-Fi and Zigbee are sitting on or too near each other potential interference problems can occur. In that case you can move either or both of your Wi-Fi and Zigbee channels...usually easier to move Wi-Fi channels.

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Thus my question here. I am getting ready to migrate from C7 to C8, and I am trying to stabilize my mesh as much as possible.

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You got a good answer in the very next post about your access point and extender. I would review settings on both and if one of them has channel width set to 40MHz change that to 20MHz. Using 40MHz increases the chance of interference.

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I had a somewhat similar experience in a power outage a couple days ago.

I had a generator running on and off. A battery backup on the hub prematurely failed and left the hub powerless for several hours.

Now, I've heard about panic mode before, but my zigbee devices are all battery powered and had been operating great until the power outage.

During most power outages here, there is no Cable Broadband service, which was the case here.

In the later stages of my fooling around, bringing the device close to the hub would re-establish comms.

I changed batteries in several devices, but same behavior.

What got things back to normal was when power, and cable broadband were restored, along with the ethernet connection to the hub.

I wonder if there's something about that ethernet connection that could be doing something? Some RF thing or whatnot?

Z-wave had no problem at all-except maybe not knowing the correct state upon mesh restoration.

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You indicate that your Z-wave lock connects through 23 hops from the hub to the lock. According to z-wave specs, a maximum of 4 hops is allowed, so something is amiss with your Z-wave setup.

By moving the position of your hub to accommodate the lock, you have now messed up all the Zigbee mesh tables. Eventually, the mesh will figure it out as Zigbee is self-healing, but it could be a mess in the meantime.

The best way to achieve smooth Zigbee and Z-wave operation is to have multiple repeaters/range extenders located throughout your home. Zigbee repeaters are inexpensive because you can purchase cheap mains powered smart plugs. I like the Third Reality smart plugs without power monitoring for this purpose.

https://www.amazon.com/THIRDREALITY-Real-time-Monitoring-Compatible-SmartThings/dp/B09KNDM4VV/ref=asc_df_B0BPY5D1KC/

Third Reality also has a slightly more expensive power monitoring plug, but these do increase Zigbee mesh traffic. Thus, I recommend against getting the power-monitoring plugs unless you specifically need the power capability. If you do get the power-monitoring version, be sure to install the Third Reality smart plug community driver and then update the firmware. That is reported to greatly reduce chatter on the mesh.

Z-wave range extenders are more expensive than Zigbee smart plugs. With the C7 hub, I needed Z-wave range extenders. When I upgraded to the C8 hub, all of my Z-wave devices, including a Schlage lock are connected directly to the hub, which is ideal. However, my hub is centrally located. If your lock is a long way from the hub, what you might do is add two Z-wave range extenders, one about 20 feet from the hub and another about 20 feet from the lock. Remember that RF waves travel in straight lines and can be reflected or stopped by metal piping, HVAC ductwork, mirrors, etc. Every time the signal has to penetrate a wall, a portion of the signal will be absorbed.

Your Internet router is unlikely to affect Z-wave, but Zigbee, 2.4 gHz Internet and Bluetooth all occupy the 2.4 gHz band, so they can affect one another. The Zigbee channels and the Internet channels are numbered differently, so you need to make sure they channels do interfere. Post number 2 above shows the relationship of these channels.

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rwclements228: Regarding zwave. On C8 the graph showed hub in center with all of my devices directly connected in a circle around it without any hops. After a couple days the graph shows a mess of routes through repeaters and only a few direct connects to the hub. Why would it change to something slower and less efficient?

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Z-wave routing is one of the mysteries of the universe, like where the city of Atlantis disappeared to, and the Loch Ness Monster. :grin:

The Z-wave mesh looks at the routes and through some algorithm tries to figure out the most consistent and fastest way back to the hub. There really isn't a way to tell the devices to route one way or the other. We can ask, via a repair, that a device look for better routes, but that doesn't force it do reroute.

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And unless there are specific problems w/Z-Wave devices there is no need to worry about the routing the devices choose. "If it ain't broke..." applies here... :slight_smile:

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danabw: it's painfully slow dealing w/ that Alfred lock. I have another one (exact same model) @ front door and it's very snappy with response time. Other then that all zwave devices work.

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As @neonturbo indicated, the z-wave protocol is smart enough to figure out the best way to route signals. Sometimes the direct route is not the best, fastest. It is somewhat like making a trip in a car. The straightest roadway might be a US highway, but the fastest roadway might be an Interstate that takes you on a longer path, but gets you there sooner. If there are no obstacles, then the straight route will be fastest, but routes that go through repeaters might bypass obstacles that can slow down the signal transmission. When looking at the Z-wave settings, the main thing to look at is the speed of the connection. If you are connecting at 100 kbps then everything is good.

Some devices, such as locks, might be limited to lower speeds. My Schlage door lock connects at 40 kbps even if it is a few feet away from the hub. That is why it is helpful to have a good Z-wave repeater/range extender a few feet from the lock that can keep resending messages until confirmed by the lock.

While Z-wave can still function at speeds as low as 9.6 kbps, if you have any connections at that speed, you have a mesh problem. There might be an obstruction. Appropriately placing repeaters can allow you to route around the obstruction.

Remember, Z-wave operates around the 900 mHz frequency. The specific frequency depends upon which region of the world you are in. Zigbee operates at 2.4 gHz, which allows much faster transmissions. However, the lower the frequency, the further the waves will travel. Thus, there is a tradeoff.

Although newer Z-wave devices allow connections with S2 security, use of that protocol greatly increases network traffic. Many forum members, including me, recommend that you ONLY use S2 security on devices that absolutely require it. Z-wave locks should be paired with S2 Access Control security to minimize the chances someone could open your door. While many other devices such as Z-wave repeaters, motion sensors, water leak sensors, tilt sensors, etc. often include S2 security, it is unlikely to be needed and you might want to consider resetting the devices to factory settings and then repairing them with the hub without any security. The only devices I have paired with S2 Authenticated security are a couple of Z-wave motion sensors mounted outside the house that have tamper resistant designs to prevent someone disabling them without my knowledge. Of course, my Schlage lock on the front door is S2 Access Control.

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Thanks to everyone who contributed to my Zigbee issue on the C8. Everything seems to be working as expected now . It's worked for the entire day. So far no issues. C7 is shut down. I fixed by relocating the smart station & changed C8 Zigbee channel to 20. C8 & smart station were both using channel 19. Started adding a new batch of devices!

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