Warning: Zigbee channel 20 utilization is 99.96%!

Auto is the default setting. (Tyranny of the default).

My neighbour’s isn’t :angry:

Mind you I have four access points and am using all 1, 6 and 11 channels. :imp:

I don’t see any issue using zigbee2mqtt ch 11 (the Ch1 wifi AP is the furthest away from the coordinator but there are repeaters all over).

In my surroundings the 2.4 GHz band is a tuna can. 50% congestion minimum. Right now it’s a breeze 60% but it usually goes to 80%, which makes it unusable except for bursty traffic. I guess I’m glad I’m not using Zigbee (yet).

Yikes. I don’t have that issue:

Screenshot 2023-12-12 at 13-31-47 UniFi Network

Why not just use (all) channels 1, 5, 9, 13 if you have exact 4 access points?

image

Because despite the image you have posted they do overlap, see the skirts in my first post above. Also the two APs that are on the same channel can’t see each other.

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Fresh anecdote.

Today we had a blackout. Power came back up and after gradually bringing all my system up (the UPS’s had let me do a graceful shutdown) started going through HA. All looked initially fine but a few minutes later my dashboards became a Christmas tree with devices going unavailable. The commonality was devices that depend on a wireless link. Took a look at the channel and almost fell off my seat:

Ok, that’ll do it. Hunting the source of such interference finally found that the AP dedicated to the cameras was on Auto channel selection and for some reason it always latched onto channel 11, killing my other AP for bursty IoT traffic. Set it manually to channel 4 and problem solved. The only casualties now are my neighbors using that channel who will get buried in my traffic.

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Another anecdote: I’ve had three Brilliant wifi smart plugs flashed with ESPHome fail in a way that they wiped out reception on the AP they were connected to. Disconnect the plug → wifi works again.

Where you able to make them work eventually?

No they actually failed (in every case just outside the 12 month warranty). I had the same problem with Kogan wifi smart plugs. Though those did not crash the wifi with interference whern they failed after 12 months.

I’ve gone right off wifi smart plugs. Removed all of them and replaced the few I do need with zigbee versions.

Same here. I had a few Brilliant devices but sold them due to to lack of integration with HA (a year and a half ago). Went with ZWave mainly because it uses a much less congested frequency.

So @odwide and @tom_l you guys have morphed this topic into a total WiFi (and a little ZWave) rant. Might I suggest you start a new topic titled ‘WiFi Sux’, or perhaps more generically ‘wireless technology sux and then I die’.

Yes, we might have. But you are welcome to whip it back into the original topic, which was what, by the way?

Ohhh!!! lovely pic. Actual network utilisation !!! I want one :slight_smile: Is that a smartphone app, or an expensive network monitoring tool ?


@scarolaa I note on your updated topology that your routers are connecting to each other and the coordinator - which is good - BUT all but one of your end devices are trying to connect direct to your coordinator … which is the exact opposite of what the mesh is for :frowning:
And before others point out, the zigbee network topology map is notoriously inaccurate. My own is still showing green links to a router which has been sitting unplugged on my desk for 3 months now !

Anyway, my visualisation looked like that and I had devices unavailable. I believe it’s because I was adding devices and routers as i went.

  1. I sat down and planned out my intended network - specifically which wifi and zigbee channels would work best in my neighbourhood.
  2. I decided to change to zigbee channel 26, which gave me an excuse to uninstall all my zigbee devices, routers and ZHA integration, reboot HA, and start again slowly.
  3. I installed ZHA and changed it to channel 26.
  4. Then install each router one at a time (otherwise they reactivate the old mesh, rather than joining the new one).
  5. Then add each device one at a time.

A fair bit of mucking about even for my 5 routers and 5 devices - but I have not noticed network problems since.

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Neither one )
It’s an HA card showing data sent by the AP over SNMP. If your WiFi device supports SNMP you could replicate this by looking at the SNMP integration and this post:

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Thanks for pointing me in that direction. It looks as though my ASUS RT-AX55 doesn’t do SNMP :frowning:

And after a bit of research it seems that once again I was swayed more by budget than support :frowning: though to be honest I bought it as an AP, then my DrayTek router crapped out so it got elevated.

You can get budget and (openwrt) support but not with a broadcom soc like with your device!

Before buying router/wifi hardware one of the few (only?) things to do is to check if the device is supported - if not it is a NO BUY (for me).

Omitting openwrt on router/wifi decreases the possible lifetime of a device drastically in most cases.

And what happened in between?

Just dropping this here, because it may be useful to people on congested zigbee channels. This tool should help you decide which channel to use. It is experimental, any feedback is welcome.

I thought that functionality was built into ZHA already?

EDIT: It is , you just download the diagnostic data, see: I tracked channel utilization with ZHA to find the best Zigbee channel - #4 by tristipasta

It would be nice if Z2M had a utility like this.

You are correct, I am using the native diagnostic data in ZHA but you only get snapshots at the time you click the download button and the congestion can wildly fluctuate in time. The script I posted will automatically do all the manual busywork you would probably use Excel for. Just drop in all the downloaded JSONs you get troughout the day, no matter how many, and you get your answer immediatelly.

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