Adding the Clustered Gateway . After you have the first gateway installed, login to the second server, where you will follow the exact same process. Except this time when you hit the next screen you will want to toggle the "Add to an existing gateway cluster" and enter in the same recovery key. By adding the recovery key and checking the box. 2. The current release covers the installation of a gateway in a standard mode and a cluster with one gateway member only. Adding gateway members to an existing cluster or gateway recovery isn't currently supported via these cmdlets. The silent install or gateway install automation can be broken down into 3 steps as shown in the image below.