Tweet
Hello,
I would like to build a site-to-site VPN with OpenVPN and use the p2p mode for this. I have configured `AES-256-GCM:CHACHA20-POLY1305` as `data-ciphers`.
How much MTU overhead is caused by OpenVPN? I would like to set this so that there is no fragmentation (inside and outside the tunnel). With WireGuard, for example, it is the IP header (20 for IPv4 and 40 for IPv6) + UDP header (8 bytes) and WireGuard header (32 bytes), so that with an MTU of 1500, the tunnel MTU is 1420. In the case of fastd, there is even extra documentation.
Does OpenVPN also have such documentation? How much overhead does OpenVPN have? How does the overhead differ if I use TCP instead of UDP?
I would like to build a site-to-site VPN with OpenVPN and use the p2p mode for this. I have configured `AES-256-GCM:CHACHA20-POLY1305` as `data-ciphers`.
How much MTU overhead is caused by OpenVPN? I would like to set this so that there is no fragmentation (inside and outside the tunnel). With WireGuard, for example, it is the IP header (20 for IPv4 and 40 for IPv6) + UDP header (8 bytes) and WireGuard header (32 bytes), so that with an MTU of 1500, the tunnel MTU is 1420. In the case of fastd, there is even extra documentation.
Does OpenVPN also have such documentation? How much overhead does OpenVPN have? How does the overhead differ if I use TCP instead of UDP?