An exception to this is if you find the smallest MTU is your local MTU at 1492, typical for PPPoE connections, then no MTU reduction should be necessary. Check the MTU on the Algo VPN server. To check the MTU on your server, SSH in to it, run the command ifconfig, and look for the MTU of the main network interface. For example:
EdgeRouter - L2TP IPsec VPN Server – Ubiquiti Networks set vpn l2tp remote-access mtu
1/14: VPN Client establishes a connection with a VPN Server via external network interface. 2/14: VPN Server assigns IP address to a vpn client from a local virtual subnet 192.168.2.0/24. 3/14: VPN Client prepares a packet for a host 192.168.1.3 located within a private subnet 192.168.1.0/24. 4/14: VPN Client encrypts and hides an original packet inside the outer public packet.
Jun 28, 2020 Your customer gateway device - AWS Site-to-Site VPN Your interface should be set to a 1399 byte Maximum Transmission Unit (MTU). When you create multiple VPN connections, the virtual private gateway sends network traffic to the appropriate VPN connection using statically assigned routes or BGP route advertisements. Which route depends on how the VPN connection was configured. How do I make MTU change persistent in Azure?
Configure VPN Settings on a DD-WRT Router for Private
How to find the proper MTU size for my network | TP-Link