If anyone is wondering what has happened to the server today, unfortunately there's been a corruption on disk of some server files. None of your data has been lost, and there are no issues with the main map. However, the main spawn was affected, and due to the way this ties into the server as a whole, we've had to take things offline while we fix it.
We are currently waiting for the data to be restored, and that is why the server is down. If it is still not up tomorrow, I will try and get something temporary in place for the meantime, but I can't promise anything. Please be patient while we wait for the backup to be provided.
UPDATE: The server is once again online and you should be able to join. If you encounter any unexpected issues, please let us know. Sorry for the inconvenience.