Hello. We were thinking about increasing the MTU on the tailscale interface since we have jumbo frames enabled on some of NICs. Will tailscale perform path MTU detection and select a MTU size which works for both peers, or will this result in ip fragmentation?
#Increasing MTU on tailscale interface
sterile heron
left plank
There is no MTU detection, we'll always default to 1280 unless told otherwise by a debug option on the daemon. You can try MSS clamping maybe, but not sure how much it would help.
To change the MTU of the Tailscale interface persistently you can set the TS_DEBUG_MTU variable to the new value in the tailscaled environment and restart the tailscaled service. For linux this is /etc/default/tailscaled and sudo systemctl restart tailscaled, for Windows it's documented here: https://tailscale.com/docs/reference/tailscaled#environment-variables