How do I set up an RTMP stream server and URL endpoint? I've got a Haivision Barracuda, which can stream RTMP to a URL (secured by username/password) set in its interface, but have very little experience of streaming video. What software do I need (Windows or Linux, but ideally free or open source at the moment) to set up a server that can provide this URL on which to receive the stream, please?

Can I then rebroadcast that (also as RTMP, to a remote URL endpoint), and how can I view the live stream to test that it's working?
If you have a Windows server, Windows Streaming Media Services works nicely and is included with most versions of Windows Server.  You just need to install the role and then configure a publishing point for the URL.  Their is a GUI provided for doing the configuration.