Is there a way to define what network the cluster communicates on? All of my hosts have 1G, 1G, and 25G interfaces and obviously I'd prefer the latter. I've been reading this: https://docs.k3s.io/networking/basic-network-options but I don't think that's the answer.

They communicate using whatever interface the primary IP is on. The CNI doesn't particularly care about interfaces, it just sends traffic to other nodes at whatever IP they are registered with and lets the kernel figure it out.

Registered with

--bind-address

right?

no… --node-ip or --node-external-ip. The IP they registered to the cluster with. Don’t mess around with --bind-address it almost never does what you want.

Oh, awesome, thanks a ton.