What is Overselling? - View from the CEO

I recently came across an article on the subject of web hosting providers overselling their server resources. Their argument was that overselling was a huge problem and that the worst offenders were resellers.

The article drew my attention for a a couple of reasons. First of all, we have clients who resell our services so some people are going to wonder if those resellers are doing anything wrong. Secondly, Hardfocus started out as a hosting reseller. That is, when we first went online in 1999, we decided to buy a resellerhosting plan from our hosting service provider. We used that account to host our own websites, and began hosting the websites we designed for our clients.

In those days, hosting control panels (like cPanel) were not very sophisticated and very few of our clients where very Internet savvy, which meant that we pretty much managed things for our clients too.

"Overselling" was really the only way to make web hosting profitable. I put this in quotes because it wasn't selling what we didn't have. It was simply efficiently utilizing the resources that we did have. Performance was never a problem because we chose our service provider carefully, and we made absolutely sure we managed our server assets properly.

Are we overselling today? Actually, we built our network with room for growth so we have a huge excess capacity in our network infrastructure. We have a ways to go before we are at the point that we have to add more server capacity. So, in a word, "no".

On the other hand, I can tell you for certain that our upstream bandwidth providers are overselling, except nobody calls it that. They are simply managing a shared resource, as any enterprise should. In short, there has ever been a time when our servers couldn't be reached do to an upstream bandwidth problem. Granted, the term "overselling" conjures the same image as "overbooking", like the airlines do. It's done every day but you don't actually hear about overbooking until a passenger gets bumped up to business class or, in the worst case, gets bumped from the flight completely. In the same sense, The telephone carriers also oversell. There are a very limited number of connections available, compared to the number of subscribers. It only becomes apparent when there is a major disaster and people can't get phone calls in or out of the affected area.

Back to web hosting. Realistically, a hosting provider's overselling becomes a concern when CPU- or memory-intensive tasks become slow, or packet throughput is poor. Such poor performance could be an indication that the resources are poorly managed. Shared resources, such as CPU, memory and network bandwidth, have average loads and a peak loads. When properly managed, the peak load will never saturate the capacity of the resource. Well, almost never. More than a few webmasters and hosting providers have learnt the hard way the meaning of the slashdot effect or DoS attack. This is very much like what the phone companies face when an earthquake or terrorist attack causes everybody to try to phone their loved ones. Calling out of the disaster area, you have to wait ages for a dial tone. Calling into the area, you just get busy circuits notification.

Unlike the often-erratic fluctuations of CPU, memory and bandwidth usage, hard disk usage is a little more predictable. It tends to gradually increase over time. Overselling will get noticed when somebody tries to upload files to their website but gets a disk-full error, even though they haven't used up their maximum storage allotment. In my opinion, if a hosting provider or reseller lets their disk space drop to zero, they have revealed a total failure to manage their resources.

Even if you are a webmaster, you have a responsibility to manage your resources. Especially if you are running a CMS (content management system) of any kind, your resources are going to get used up. How fast will be closely tied to the popularity of the particular website. More content updates brings more visitors which use up more resources.

If you are a Hardfocus client or reseller, you should be regularly checking your resource usage, which cPanel lets you do. When you see usage increases you should be considering when and how much to increase your capacity. If there are any sudden changes, you should be looking at why. Failure to do so might lead to some nasty surprises down the road for both you, your clients and/or your website visitors.

Stephen Brown is founder and managing director of The Hardfocus Media Group. Articles like this are Stephen's personal take on issues that relate to Hardfocus, its services and its clients.