Your router isn't meeting the requirements, but you might still be okay.
Your router isn't meeting the requirements, but you might still be okay.
Hey there, I see you're trying to link a server to a PC through a personal VPN. You're using Windows Server 2019 and Windows 10, with a Netgear C7500 router. From what you've read, it seems your router isn't handling GRE packets well. That could definitely be a problem. Are you sure this is the main issue, or are there other factors at play? Let me know how I can help!
Are you checking if your ISP uses CGNAT with a VPN tunnel? Which way do you want to link—outbound to your home network or the opposite? How are you verifying that GRE traffic can't be routed through the router? Is there a dedicated ISP box after your router that might block it automatically?
You can check if your ISP uses CGNAT by trying to connect from an external network while both your PC and server are on the same home network. Since you have a third-party VPN, you might need to configure it properly. You mentioned you already allowed protocol 47 and GRE packets through your router and server firewall, but they didn’t work on the router itself. If port 1723 remains blocked despite those settings, it could indicate an issue with the ISP’s configuration or a misrouting at the network level.