I understand that by default wireguard chooses an MTU of 1420. The way that I have setup wireguard now is that I have a router (running LEDE/openwrt) connecting to wireguard running on an arch server. I then set the default gw to go through wireguard and properly do iptables nat masquerading so that the only ip inside the tunnel is the ones in allowed_ips. Basically all my traffic from the router (lede/openwrt) now flows over wireguard and then to the internet. - Router -> wireguard -> Internet - working good because the MTU is properly set to 1420. - Wifi Client -> Router -> wireguard -> internet - Not working properly because of MTU is set at 1500 at wifi/wired dhcp clients. How do we propose that we advertise the correct MTU that the NAT clients of the router should use? Is there any other way to solve this issue? Thanks, -- *Ibrahim Tachijian* CEO Net Sat AB Mobile: +46723321377 barhom@netsat.se _________________________ *Net Sat ABC/O Jayway AB*Klara Ă–stra Kyrkogata 2B, 1TR, 111 52 Stockholm, Sweden Office: +46 (0)8 408 394 53