Recently I started using OVPN to my home network to access local service like openclaw gateway.
There is one bug, been zero package received after successful TCP connection. Initially I thought it TCP over TCP issues since I’m using the 5G cellular network to connect to the VPN.
After Changing it to UDP, It still delivered zero package. After some digging the issue is on kernel IP forwarding been off.
net.ipv4.ip_forward = 0
And also having no NAT rules.
iptables -t nat
So what happen is basically Package sent to the Debian machine and no package been routed. Obviously, since no package been routed OVPN on my phone get zero package, hence the upload and download speed been zero.
