How do IPv6 Router Advertisements get across VLANs?

[barney]

If the Dirigera has no internet access, how can devices behind it have internet?

Neither the Dirigera nor any of the devices behind have internet access (see note below) - all of my monitoring / automation is local using openHAB. If I want to access stuff remotely I can VPN in to my openHAB server and control it via that.

Note: I did need to allow the Dirigera internet access when first commissioning it as it wanted to check / download the latest firmware before letting me do anything. I'll also open that up again if later firmware is released. If specific device firmware updates are release I may need to allow the devices internet access at that time.

I have no real problem with connecting stuff to the cloud if they need it, but as a general approach I just don't let anything out unless I want it to - not because the manufacturer wants it! If I do ever get a device that really does require cloud access then I'll create a rule to let that out.

I shouldn't have assumed how your environment is.

No problem - I appreciate you taking the time help.

[mooh]

I think I must be using the latter... all of the matter devices in the thread network have a ULA IPv6 address that is routeable across the network (Dirigera supports Matter 1.4 if that makes a difference) - this is the address that is published in the mDNS message.

Very interesting. Looks like I have some reading to do, especially why there are multiple ULAs per device. Anyway, ULAs are not globally routable, just like link-local addresses. So my basic point is still true. These devices cannot reach the internet without some sort of proxy and none of your local networks without routing support.

Do you happen to have multiple thread networks in your home?