For all those who have separate Remote Desktop Web Farms and Gateway Farms, why not use KEMP‘s LoadMaster to load balance both services over a single Virtual Service (IP Address). This can be easily achieved by using Sub interfaces.
Some important info before we start, Before Server 2012, the RD Gateway used a single HTTP Channel. Post Server 2012, the RD Gateway uses two channels (one for Input & one for Output). This means that these channels need to be routed through the same RD Gateway Server. You will need to use a Load balancing mechanism that supports IP affinity, Cookie-based affinity, or SSL ID-based affinity. RD Gateway now uses a new method based on two HTTP channels. Freek Berson RDS MVP has published a great article that discusses the use of KEMP’s Azure VLM to Load Balance RDS in a Laas environment. Please see the following link: http://kemptechnologies.com/blog/load-balancing-remote-desktop-services-web-access-gateway-with-kemp-load-master-for-azure/#!
Ensure you import you external certificate into the LoadMaster.
Create your Virtual Service.
Create two Sub interfaces, one for RDS Web Services and one for RDS Gateway Services
Once you have added your first Sub interface, the option to add a real server disappears. Add the second Sub interface.
Configure both Services to use HTTPS (443)
You will need to make sure that the RD Gateway is configured for IP affinity or cookie based affinity to support the two HTTP Channels.
Once complete you should see both services up:
There you have it, RD Gateway Server and RDWeb Services load balanced using Sub interfaces on KEMP.