1. Make sure the FMS processes are running. On windows, you can look in the processes tab in the taks manager. You should see FMSAdmin, FMSEdge, FMSMaster, and FMSCore. I don't speak penguin, so I don't know how to check on Linux.
2. Make sure ports 1935 and 1111 are open on your firewall.
3. Try hitting the admin service through a browser to see if it responds. The address will be http://[your server ip or host]:1111/admin .Replace [your server ip or host] with the IP or host name of your FMS server. If you don't get a response, check items 1 and 2 again.