I saw this post: Change PPTP control connection's TCP port number and I successfully did it on my PC. But how do I change Android's PPTP VPN client's port number? My Android phone is rooted and I installed a terminal emulator so I can run Linux commands.
Using VPN through an MX Security Appliance - Cisco Meraki The MX security appliance is designed to be used as a VPN endpoint, but as a firewall it can also pass VPN traffic to an internal VPN endpoint. PPTP and IPsec are protocols used to establish a secure encrypted VPN connection between two end points. VPN Port Numbers - Virtual Private Networks (VPN) - Tek-Tips May 02, 2002
How to check if you can connect using PPTP on Windows - ibVPN
Enable VPN passthrough DrayTek router - VPN Questions and Oct 21, 2015 How to Enable VPN Passthrough - IPsec Firewall Port - Tom
Change PIA PPTP/L2TP/OpenVPN Port Number on Linux - YouTube
Jul 15, 2020