On my Flint 2, I have enabled guest network, which is on a separate subnet. I also have the AP isolation option on.
My question is, is the traffic on the guest network broadcasted on the main network? I have put my smart lightbulbs and plugs on the guest network but it appears that I can still turn appliances on and off from the main network. I don’t mind this, but I do want to know if the guest network traffic is broadcasted on the main network, or if both networks are treated as their own broadcast domains.
My understanding is that as long as two or more networks are using the same router, the two networks can communicate with each other.
Can you ping your main’s network clients from the guest ?
No. When I am on the guest network, I cannot ping the main network clients at all. I can’t ping the guest network default gateway either.
When I’m on the main network, I can ping both default gateways, which tells me that the networks can at least talk to each other, which is fine with me. I’m more worried about making sure that the broadcast domains are separate so my network doesn’t get too chatty.
Check your Firewall rules in Luci. Default is Guest only has access to WAN.
Silly question but do they might have an internet service for it so there is no direct connection is needed?
I am not quite sure what the AP isolation does. However, if you are concerned about broadcast domains interference you can do it through VLANs.
You can run witeshark/tcpdump on a client connected to the main network and see what’s going on. You can also send broadcast arp request from a guest client and monitor your tcpdump.
Routers, unlike switches, do not forward broadcast traffic .
Very good reference: Broadcast Domain
And on a tangent here but I have moved my HASS devices to Zigbee. They have no Internet access and are on a local Zigbee WiFi network separate from the router.
The advantage of this is security, and offloading “stuff” from your regular data WiFi on the Gl-Inet routers.
Thanks, Spitz. Forgot about ARP broadcast requests lol. I ran a tcpdump from my Mac on the main network and I was only getting broadcasts from clients on the main network as intended, while still being able to reach devices in the other network.
Glad you have verified it