Initial data:
192.168.0.1/24
192.168.0.0
Ovpn server: 192.168.0.1:1194
Protocol: TCP
Using these settings, OVPN works:
Note: only works with Blowfish encryption, no compression.
Additional options in Grandstream phone settings,
don't forget about the route:
client;
devtun;
resolv-retry infinite;
nobind;
tls-client;
auth SHA1;
Route 192.168.0.0 255.255.255.0
Source: habr.com
