It was necessary to null route the IP address associated with most our the sites on that server. Customers on dedicated IP addresses should be showing no issues right now.
What we are doing: We are changing IP addresses. Resellers are getting a new unique IP address so that we can narrow down the search for exactly which site's are the target of this massive attack.
As soon as your sites resolve to their new IP addresses you should be able to access them.
This process may or may not bring on another DDOS. If it does we will continue the process of terminating all traffic to the said IP until we have a final solution.