Thank you for your suggestion. I tried to connect on router LAN port 80 TCP and weird lines immediately appeared in the syslog. This is strange as the OpenVPN server should listen ONLY on the WAN-side port 80, not on the LAN side. Am I wrong?
OpenVPN listens to all interfaces, both WAN and LAN. Might be handy for testing to have it listen on the LAN side. Anyway, you'd still get WAN-side connections to port 80.
I am forced to do this as I am traveling a lot, also my daughter is studying abroad, so very often we are in very paranoid environment. Some organisations like universities, companies and hotels are trying to filter everything except TCP port 80 and also are using HTTP proxies, so connecting to my home OpenVPN server could be impossible. The only solution is to configure the OpenVPN server on TCP port 80. This always guarantees connection as at least port 80 is open on every public network. I had several problems in some places when I used standard OpenVPN ports.
I would recommend putting it on port 443 then. At least it will limit the number of unexpected connection attempts, and port 443 should still be open from pretty much anywhere (this is the HTTPS port).
Merlin, do you have any ideas about problems with existing Entware installation described in my previous posts?
No idea short of your device getting mounted on a different mount point. As I said, I don't have that problem with either my AC66 or N66. I do mount each of them through a label rather than their device names however, makes it more stable.