[anabab]

can you still set up direct connection between a switch and a light which would work even if the hub is down?

[Dextro]

Yes! This is called binding in zigbee parlance. I have a couple of ikea bulbs and switches and, if memory serves me, you can bind up to 10 bulbs to a single switch.

[SparkyMcUnicorn]

All zigbee devices require a coordinator. It can be a raspberry pi or any other hardware/software with the radio, but it does have to be powered up.

[t0mas88]

This is not true. Look into Zigbee binding, it works when the coordinator is offline.

I'm using that as a backup solution in my house. All lights are zigbee, permanently powered, normally most are controlled automatically by presence sensors. But I have a couple of Zigbee remotes in a box that are bound directly to the lights to use in case my home automation system is down.

[SparkyMcUnicorn]

I'd modify my comment if I could. Bound some remotes to some hue bulbs, proving myself wrong.

[Tijdreiziger]

Not all, IKEA Trådfri works fully hub-less by default.

[SparkyMcUnicorn]

TIL I can bind my remotes to my Hue bulbs, and they work without the coordinator.

[sp332]

So how do the Hue light switches work?

[cj]

Hue light switches (well, the ones I have) simply stick on the wall with no wiring.

The _real_ light switch is permanently on, and the _hue_ light switch sends a beacon to the hub to turn the configured lights on/off (the light bulb socket is always-on)

[talkin]

No, some switchers and dimmers can also control lights without a hub present. Some products come as a paired bulb and switch, with only an optional suggestion that you later extend into the ecosystem.