I know this is not a solution to your problem, but I have found myself more often running the public interface of openvpn systems on port 443. Any sufficiently advanced DPI setup will be able to tell that it's not quite normal https traffic.

But 99% of the time it seems to serve the purpose of defeating heavily-restricted "free" wifi in airports, hotels, random guest/amenity wifi stuff, which obviously can't block https/443 to the world these days.

On Fri, Sep 10, 2021 at 11:08 AM Jason Kuehl <jason.w.kuehl@gmail.com> wrote:
This is an SSL VPN that is being blocked. This is what failure looks like. Curl is the same.

Once we disable the Xfi  Advanced Security everyone can connect.

image.png

On Fri, Sep 10, 2021 at 11:01 AM Jim Popovitch via NANOG <nanog@nanog.org> wrote:
On Fri, 2021-09-10 at 10:31 -0400, Jason Kuehl wrote:
> For whatever reason Comcast Xfinity is blocking my VPN URL.

Not certain that this applies, but Concast Advanced Security (setup in
your Comcast gateway) only allows outbound VPN connections to UDP ports
500, 4500, and 62515 and TCP port 1723.

-Jim P.



--
Sincerely,
 
Jason W Kuehl
Cell 920-419-8983
jason.w.kuehl@gmail.com