Fairly new to tailscale, have scanned the forums and cannot see anything similar so hoping someone can advise if the behavior I am seeing is considered normal.
I am running TS in a k8s container, setup as a subnet router with appropriate (I believe!) forwarding and firewall rules set. I have split DNS in play and route everything destined for my domain to my own DNS servers. Other requests are sent via local DNS I am not using override.
It works perfectly.
Except… I note that when I am in the same local network on a device (iphone in this case) as the subnet router, if I make a DNS lookup for an internal host, the subnet router fires up a link to a relay to route the request back to the DNS servers that reside on the same network I am connected to, once the lookup has been done the connection proceeds as expected over the local network, I have confirmed this using tcpdump, additionally tailscale status shows the device as idle once the initial lookup has been completed.
This perplexes me a little as I would not expect there to be any need to connect to a relay when the DNS servers are one hop away on the same network as the client.
I realise k8s adds some complexity to networking and can provide many more details if there is any interest, just dipping my toe in the water here.