I think the documentation on Samhain's website is very poor so I decided to write up some of my notes. I'm running Samhain 2.4.1 with a server and some clients.
Samhain
Run the server in foreground mode so you can see the errors it is throwing like this: `yule --foreground'
Make sure the hostname, forward DNS and reverse DNS all match up to what is in the yulerc of the server.