All of our newer servers use dedrelay.secureserver.net
.
Your server must send mail using our relay servers. This prevents abuse of our network and helps ensure our customers don't get blacklisted for using the same network as a spammer.
For the most part, you do not need to worry about these settings unless something is not working or you want to use a different mail server daemon on your dedicated machine.
Our servers have an outbound email limit of 1000 per day. If you need to send more than 1000 emails per day, contact customer support.