Global discovery doesn’t necessarily mean lower upload rates. I am sure your router is clever enough to understand that even though it’s being asked to send packets to an external IP, it’s actually already within the local network.
If you know a way to test that, let me know. (Problem is, I have a decent upload rate, but the device with multiple instances is a low power arm device. So benchmarking is a bit problematic, it would be better to know what the router does.)
I am sure that your bottleneck will not be your router, but your low powered device, or syncthings overhead.
I’m sort of curious why my internal dev Sandbox has syncthing switch from ipv4 to ipv6 based on the wireshark logs. It’s on an internal vswitch on two Ubuntu 14 machines in vmware. Is this a feature ? Confused 'cause I never have used ipv6 actually, heh.
There’s no real “switch” involved. Discovery will use both v4 and v6 where available. First that is found and connects is used.
Thanks Jakob, that explains it.