Why you need clustered hosting for your website

Friday, 01 January 2010

If you're an online business and you're not concerned with guaranteed up-time, then you should be.  People visit your website twenty four hours a day, seven days a week, every day of the year, so every minute that it's not available due to server problems or technical failures, is costing you money.  Most web hosting companies offer guaranteed up-times of 99% or even 99.9% - but they can never guarantee 100%.  Servers can and will go down occasionally, and even that 0.1% of downtime could have an impact on your business.  Web hosts know this, and one of the ways they work to reduce that impact is through clustered hosting.

What is Clustered Hosting?

To understand clustered hosting, it helps to understand the more traditional model, which is standalone server hosting.  With this system, all web services are run on one machine - everything from the website control panel to the email server to file transfer protocols.  This is obviously a lot for a single machine to cope with.  You can see this with your own PC.  If you have lots of programs all running at the same time - email, web browsing, word processing, anti-virus protection and so on - they inevitably run slower than if you had just one or two running at the same time.  Use too many at once, and they start to slow down or fail altogether.

Exactly the same thing happens with standalone web servers.  Indeed, the problem is even more acute for web hosting companies, because one server has to cope with multiple web sites.  So it's not difficult to imagine why websites go down from time to time.  You might even think it's something of a miracle that they're available as often as they are!

Clustered hosting aims to alleviate this problem by sharing the burden of running website programs across several servers.  This is like having multiple jet engines on an aircraft - if one or two fail, the rest can keep the plane in the air until it's safe to land.  Clustered hosting protects each website from its neighbors.  If your website runs a particularly heavy database, for instance, the fact that it's distributed across several servers means that other websites won't be affected by what you're doing, and vice versa.  Clustered hosting also minimizes the effects of sudden spikes in traffic or bandwidth use.

This is also a useful solution to the problem of rebooting and upgrades.  Rather than taking down the entire network when a reboot is required, websites can be kept running on other servers in the cluster whilst the reboot or software upgrade is rolled out across individual servers by degrees.

In the end, if you're looking to host your business online, you need to make clustered hosting part of your due diligence process.  You need to know that your web host understands the need not to put all their eggs in one basket, and that the ever-increasing server load is spread out across a clustered platform.  Anything else could cost you very dearly indeed.