Or stop waiting for them to add providers! The fact Sophos XG is so awesome and supports DynDNS but does not let you specify a server address is impossibly stupid IMHO. Here is how to use Sophos DynDNS with any DynDNS compatible provider like no-ip.com:
Login to admin.
Click Network -> DNS
Then scroll down to "DNS Host Entry" and click ADD:
Host/Domain Name: members.dyndns.org
Entry Type: Manual
IP Address: 8.23.224.120 (You might want to do a dns lookup of this to see if the server ip has changed - or resolve the provider of your choice's ip and use that instead - and this is the rub with this setup - if the provider changes the server ip it breaks)
Time to Live (seconds): 60
Weight (1-255):1
Publish on WAN: unchecked
Add reverse DNS lookup for this Host entry: unchecked
Now configure Dynamic DNS but use the no-ip.com username and settings. It works for me!
