Smart Switches that Still Function if Home Assistant is Offline

[subtle belfry]

Hello everyone, I'm somewhat new to the Home Assistant ecosystem and smart devices in general. I've setup a working voice pipeline and Wyoming Satellite and that's how I've been controlling the Zigbee lights for the past few days but now it's time to replace my light switch. What I would like advice on is for a smart switch that can turn off and on the light even if Home Assistant is offline. I'm not sure what this would be called or if it's standard behavior and this point.

[meager jungle]

I use Hue remotes bound to ThirdReality lights to accomplish this

[daring forum]

as long as the switch uses direct binding

[unreal plume]

The sonoff relays that sit inside the backbox still work when HA is dead. ZBMINIL2.

[meager jungle]

Alternatively, any smart switch that's actually physically controlling lights should still work even if HA is down, but it sounds like you're using smart lights as well (hence what I shared above)

[subtle belfry]

I have ThirdReality lights as well. So the Hue remotes are paired directly with the lights not HA?

[unreal plume]

So HA is bound to the switch and the switch is bound to the (smart) light bulb?

[meager jungle]

They're paired to the zigbee network like normal, but I've bound the genOnOff and genLevelCtrl clusters to a zigbee group with the lights so that the remote controls the lights directly even if the zigbee coordinator or zigbee2mqtt are down

HA can still see the _release actions (on, off, down, up) so I can still use the remote in other automations too if I want

zigbee2mqtt docs on binding

[subtle belfry]

Interesting.

[meager jungle]

sorry, what?

[unreal plume]

I’m trying to understand how the light can be controlled by both HA and the switch.

[meager jungle]

@unreal plume The switch (which is really just a remote) and the lights are all paired to zigbee2mqtt. The remote is also bound to the lights directly which doesn't impact the connection to either zigbee2mqtt or, by extension, HA

[daring forum]

i guess the zigbee coordinator needs to be powered though, so if HA is off > Zigbee is off without always having power on USB

[meager jungle]

it doesn't

binding works even if the coordinator is offline

[daring forum]

aah ok

[pseudo cairn]

many of these switches are designed to send commands directly to connected bulbs through the zigbee mesh. for some of them, the connection to home assistant could be thought of as a "hack" - home assistant sets up the coordinator so it can receive e.g. light control commands, then binds the switch to send commands to the coordinator.

[pseudo cairn]

looking at the zha quirks for some of these is kind of interesting - you can see how they map backwards from the commands that the remote sends to figure out which button was pressed: https://github.com/zigpy/zha-device-handlers/blob/dev/zhaquirks/ikea/fivebtnremote.py#L120 (for example, on line 132, if zha receives a command from this remote to "step the light's brightness up, and turn on the light if it was off", then it interprets that as meaning the "Dim up" button was pressed for a short time.)

[unreal plume]

If HA or Zigbee to HA was unreliable this might all have value. In 2 years I’ve never had a problem (touch wood etc) that makes me think about high availability or devices needing to work independently of HA.

[somber kernel]

also check out Shelly switches. you wire the real switch to it, and it toggles the internal relay that is wired to your appliance, no matter if the zigbee/wifi/whatever connection is up

and of course the internal relay is controllable through HA

[somber kernel]

i'm also thinking a lot about high availability, like having the switches store a backup automation (Shelly firmware has schedules) in case the wifi goes down for more than X hours, so critical appliances like the water heater continues like nothing happened

but at one point it's a lot of added complexity hence potentially buggy behavior, so you must weight that against the actual risk of outage