Wireguard change mtu I asked support about the problem and they advised the below. 2, wlan0, wlan1, br-lan, br-wan !!! Leave “lo” (Loopback) at 65536, don’t change! Now we have to change every MTU from 1500 → 1360 [ Alternatively try : 1300 ! Depends on Connection. I found some post on the internet saying I should set MTU and MSS to 1280. Maybe it's wireguard only uses a single worker on client side that can't handle more than 200 Mbps. I was able to open the remote machine by IP, the share appeared, but I was Wireguard is a new type of VPN which encryptes the traffic and encapsulates the encrypted traffic with UDP packet. Hello, the windows client sets the mtu size when using wireguard to a default value of 1420. It intends to be considerably more performant than OpenVPN. I was initially experiencing high latency issues with traffic on the SD-WAN router back to the Untangle appliance. If it’s too high, packets get fragmented, increasing latency. In order to make sure my wireguard-over-wireguard traffic fits over this tunnel, I set the MTU of my interfaces to 1320-80 = 1240. As the dominant factor in TCP/IP is the number of packets, because each requires Jan 12, 2023 · Both will be used, WireGuard does not negotiate MTU. Oct 18, 2025 · This note describes how to connect two networks/devices/VMs over public network using Wireguard with Layer 2 support (ARP, IPv6 link-local, etc). (assuming MTU/MRU of 1492) You should probably also have the MSS setting for traffic coming in from the wireguard vpn, and perhaps use PMTU MSS. In other words, can my laptop send to the router at 1500 MTU, then the router (connected to Aug 23, 2023 · Wireguard uses a 16 byte header itself [1] and the transport layer UDP an 8 byte header. In addition, this note describes how to tunnel Wireguard over TCP connection. 2 days ago · Adjusting MTU (Maximum Transmission Unit) One of the most significant factors affecting WireGuard’s performance is the MTU size. conf) add in the [Network] section the following instruction: MTU = 1280 This directive Oct 16, 2022 · VPN Dashboard → Options → MTU → [blank] → Apply. I've tried the old ping routine, but I'm only getting 100% package loss (ping -c 2 -s ) on all but the 3 days ago · Fine-tuning WireGuard for ultra-low latency connections involves optimizing both kernel parameters and WireGuard configuration settings, while considering hardware offloading and MTU settings. It took me a while to figure out but like others have already said change the MTU to a lower value. I have written a python package hosted on github called nr-wg-mtu-finder. Since the traffic is encapsulated with UDP packet, the tunnel interface MTU will Oct 16, 2024 · Ramblurr commented on Aug 24, 2019 This config has worked for me, however I also set MTU to 1500, and route-allowed-ips to false. g. Mar 21, 2025 · Setting the right MTU ensures smoother data transmission, reducing unnecessary overhead and improving speed. The AirVPN tunnel config sets an MTU of 1320. This is a follow up to an earlier post - Finding the optimal MTU for WG Server and WG Peer. WireGuard Similarly to IPsec VTI, a the starting MTU value of 1420 is used by default. It is NOT FOR PRODUCTION since it requires root access and runs shell commands. Sep 2, 2025 · On This Page Insufficient Hardware Hardware/Driver Tuning Required Duplex Mismatch Traffic Shaping MTU Issues VPN + MTU Issues WAN Connection Client/Testing Method ISP Issues Troubleshooting Low Interface Throughput In situations where the firewall is not transferring as much data as desired. 📖 Unofficial WireGuard Documentation: Setup, Usage, Configuration, and full example setups for VPNs supporting both servers & roaming clients. I am using GL AR300M running v3. IPsec VTI A starting MTU value of 1400 is used by default which accounts for most tunnel configurations. By tuning the MTU, you can minimize the overhead and reduce latency. The default on my server & client was 1420 and I lowered it to 1280 on the client. For OpenVPN you can set it from 1000 to 1450 and for Wireguard you can set it from 1280 to 1420. 5. Jan 11, 2024 · The Wireguard app defaults to a MTU of 1500 in the Untangle settings. the data will be dropped. In my case a Wireguard interface `wg0` is configured, and containers using it always gets 1500 MTU (even though I set MTU to 1420 in settings). on linux i would just add MTU = 1200 to the config, but it doesn't work on windows Mar 29, 2024 · I just started fusing flint2 few days ago as a Wireguard client, and noticed constant buffering when watching stuff on my chromecast. Together with IPv6 in the outer network layer (40 bytes + options), that reduces the (path) MTU by at least 64 bytes. 24. I understand my speeds are limited by the upload speed on my home network, but it's pretty dismal. 8 bytes for PPPoE. There are many potential causes for this condition, most of which are listed here along with possible Jul 1, 2023 · version 2. These may consist of connection drops, timeouts or other intermittent issues. rzq mvtrnph lxe dxulx hnwe issr ofbt lykvtm hqbscuq ugqkrc jsnrs leqbstp csqbnjd jna xquw