VPN over DNS/ICMP configuration help

hajekj · Post by **hajekj** » Sat Jul 23, 2016 9:24 am

Hello,
I am running the most recent version of SoftEther Server and Client. I can successfully connect to the VPN over SSTP (from Windows), L2TP (from my phone) and through SoftEther client. However, when I for example connect to a Wi-Fi with captive portal - DNS queries are enabled (I can nslookup pretty much anything) - I can't connect to VPN - I would expect VPN over DNS to be used.
What the network does is, that it redirects every HTTP/HTTPS request to the captive portal - isn't the issue there?
Honestly, I don't know how the protocol selection works so maybe the issue is that the VPN can see the server as "reachable" despites the fact it cannot connect to it so it doesn't try the VPN over DNS and rather throws timed out error.
VPN over ICMP and DNS is allowed on my server, and port 53 is open on my router (just like 443, 4500 and 500).

Can you please provide any help?