Multiple Forefront UAG servers can be combined into an array.
To deploy an array you need to:
Managing an array consists of:
If you join an UAG server to an array, and do not finish the Getting Started Wizard properly as instructed you may run into issues. For example you can see the following error message:The UAG configuration cannot be retrieved from Forefront TMG storage.
An error has occured and UAG will close. Check that TMG services are running. If the UAG server is a domain member, verify connectivity to the domain controller.
To resolve this, open UAG Management on the new member you are trying to join and finish the Getting Started Wizard as instructed. Note that you will receive explicit instructions by the wizard.