A question came up discussing this with a friend.
Can you reuse the WFE you setup for SharePoint to run Office Web Apps?
The answer is – NO! (and no exceptions to this rule).
All servers in the Office Web Apps Server farm must be part of a domain.
They can be in the same domain (best practice) or in domains that are in the same forest.
Review these guidelines carefully:
- Servers that run Office Web Apps Server must not run any other server application. This includes Exchange Server, SharePoint Server, Lync Server, and SQL Server. If you have hardware constraints, you can run Office Web Apps Server in a virtual machine instance on one of these servers.
- Do not install any services or roles that depend on the Web Server (IIS) role on port 80, 443, or 809 because Office Web Apps Server periodically removes web applications on these ports.
- Do not install any version of Office. You must uninstall Office before you install Office Web Apps Server.
- Do not install Office Web Apps Server on a domain controller. Do not install Office Web Apps Server on a Windows Server that is running Active Directory Domain Services (AD DS).