HA OS Can't discover devices on 2nd subnet

There are two subnets in my house Subnet 1 > 192.168.1.x (Ethernet) and 192.168.2.x (Google Nest WiFi). VLANs with inter-LAN enabled ensure traffic can flow between the subnets.
HA OS is running via Oracle VirtualBox on a Windows machine on Subnet 1. The Windows machine has WiFi enabled and can successfully ping WiFi connected devices on the second subnet.
HA OS cannot see these devices and using terminal cannot ping the same device. E.G. 192.168.2.63.
Is there something that needs to be enabled in HA OS to allow for this if the host machine can see them but the HA install cannot?

  • host only has wifi? or both wifi and ethernet?
  • which interface is bridged for the vm?
  • is the v nic in the same subnet?

The various discovery mechanisms mostly operate on broadcast (or multicast), so they don’t cross subnets.

The simple fix is to use a single subnet.

The complicated fix is to add in mDNS reflectors, which (if done correctly) will enable some to be found.

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I know OP talks about discovery, but the fact that he can’t even ping the devices he want’s to discover,
would lead me to believe, some more basic settings are already wrong.
so no only will autodiscover never work that way,
i think even manually addressing them wont work too…

Why not having HA in the second subnet vlan and have another interface in the main vlan for Web UI access?

Can you use tagged vlan?

I don’t think HA OS is the issue here, but how virtual box handle networking, for your use case you better use bridged network or dedicated lan with passthrough, you might need to install hyper-v on your host

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You should look at this right above where I asked a question and responded. I outlined what my vlans are and this response below is basically the easiest way.

Send a trunk port to your HA, then add virtual interfaces to HA so HA has a physical IP on that subnet, and the vlans remain isolated, vs trying to have routing in place.

well the broadcast packets is probably not broadcasted where your home assistant’s network is placed. and this is intended and work as advertised, after all vlan’s main job is to segregate networks.

how to fix this? well all I can say is add a 2nd (virtual) NIC configured to be connected to that iot vlan, in that case any broadcasting happening on that iot vlan can now be seen by home assistant.

there are other solutions like mdns proxy and stuff, but its easier just have your home assistant join that network instead.

Nest mesh Wi-Fi always creates different subnet unfortunately.

I’ll try some different network options in VirtualBox and see Amy work. Thanks.

@BenoitAnastay It was as simple as ignoring multiple complex instructions and solutions elsewhere and reverting back to using two bridged network adaptors in Virtualbox:

  1. Bridged - Ethernet
  2. Bridged - WiFi
    Gave them both static addresses and restarted the VM, could then ping the devices from the HA terminal.
    Thanks for your help.
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dear pegasus829 could you please help me understand how to actually do it by providing a couple of screenshots buddy?

My problem is that I just bought a mesh H80X connected via ethernet to the SP router and as im having a subnet, this subnet does not detect HA

Thanks