Why do you require me to use your dns servers for hosting?

One of the requirements in our terms of service that people occasionally ask about is the requirement that you use our dns servers for resolution of domains that are hosted with us.

The reason we require this has to do with the way we perform load balancing adjustments and hardware upgrades.

Load Balancing

We are fanatical about keeping server load down to ensure that your website performance is stellar. Sometimes this requires us to shuffle a site or two from server to server. As sites mature and begin to attract more attention and traffic, they can increase the load on the server. We keep our site/server ratio low enough that our Linux server load is almost always well under 1. A load of 1 roughly indicates that one CPU or CPU Core is running at 100% capacity, and our servers all have multiple, multi-core CPUs, so the target value at which we prefer to keep servers is significantly well below the server's processing capacity. This is how we attain peak performance for your website.

Occasionally we may have to move a website from one server to another in order to maintain the proper load balance across all servers. When we do this, as long as your are using our DNS servers, the move is transparent to you. This is because the cPanel control panel system which powers our servers has build in site migration facilities that move an entire website and all its related files, databases, email accounts, etc. to a new server and then update our DNS servers with new IPs, making the move smooth and unnoticable to you.

If you are using external DNS, when we perform a site migration your DNS servers continue to point to the same IP you set at your external DNS provider. Because we do not notify you on load balancing adjustments, when we deleted the old site you'll simply not be able to access your website until you update the IP address with your external DNS provider.

Hardware Upgrades

We also upgrade our hardware every 2-3 years, installing brand new equipment to keep your website running on current hardware. When we do this, we will install a new server in our data center, and then migrate an entire server of websites to the new server. The same DNS issues apply to this scenario as apply to load balancing.

Full DNS records management in cPanel

One of the primary reasons you might think you should use external DNS is so you can create and manage additional DNS records that point to external hosts. This is not a problem, as cPanel gives you a complete DNS records editor, so you can fully maintain the zone file for your domain and create as many additional DNS records as you need.