Recently, on a cruise on Oceania Cruise line, I was able to access my webmail at webmail.dynu.com but not the control panel at dynu.com when logged into the ship's wifi. I spoke to the ship's crewmember responsible for wifi/internet access and he confirmed that it was blocked by their fortinet firewall and, after contacting the headquarters in Miami, he confirmed this is corporate policy. I asked why they do not block sites such as GoDaddy and he explained that it was because of the DDNS service that is offered and that because of that, the site would not be whitelisted.

Obviously, I can avoid this issue by usig a VPN but as I currently only use a free VPN service, the performance is slower - not the mention the hassle, albeit minimal, of logging into the VPN.

So, the question is whether thier is an alternate URL or alternate method to access the control panel without using VPN or being blocked by the cruise ship firewall.