This article describes the technology behind multiple server hosting and how you may utilize it to maximize your site's security and uptime
Hosting of web sites has essentially become a commodity. There is very little distinguishing one hosting company from the next. Core plans and features are the same and price is no longer a true determining feature. In fact, choosing a host based on the cheapest price can be more expensive in the long term with respect to reliability issues and possible loss of sales as a result of website downtime.
Selecting a host from the thousands of providers and resellers can be a very daunting task, which may result in a hit and miss approach. But although hosting may have become a commodity, one distinguishing feature that you must always look out for is reliability.
At the heart of any hosting company's reliability is redundancy. This ensures that if a problem exists at one point, there will be an alternative which ensures continuity as seemlessly and transparently as possible.
Most hosts do employ redundant network connections. These are the high speed pipes that route data from the server to your web browser. But, redundant 'multiple web servers' have been extremely rare and very expensive, requiring costly routing equipment which has previously been used only in mission critical applications of Fortune 500 companies.
However, a very neat but little known Domain Name Server(DNS) feature called 'round robin' allows the selection and provision of a particular IP address from a 'pool' of addresses when a DNS request arrives.
To understand what this has to do with server reliability it's important to remember that the Domain Name Server (DNS) database maps a host name to their IP address. So instead of using a hard to remember series of numbers (IP address) we just type in your web browser www.yourdomain.com, to get to your website.
Now, typically it takes at at least 2 to 3 days to propagate or 'spread the word' of your DNS info throughout the internet. That's why when you register or transfer a domain name it isn't immediately available to the person browsing the web.
This delay has stymied the security benefits of hosting your site on multiple servers, as your site would be down for a couple of days if something went awry with one server. You would have to change your DNS to reflect your second server and wait days before the change was picked up in routers on the internet.
However, the round robin DNS strategy solves this predicament, by mapping your domain name to more than one IP address.
Select hosting companies now employ the DNS round robin technique in conjunction with'failover monitoring'.
The DNS round robin failover monitoring process starts by a web hosting company setting up your site on two or more independent web servers (preferably with different IP blocks assigned to them). Your domain name will therefore have 2 or more IP Addresses assigned to it.
Then the failover monitor watches your web server(s) by dispatching data to a URL you specify and looking for particular text in the results. When the system detects that one of your IP addresses is returning an error, and the others aren't, it pulls that IP address out of the list. The DNS then points your domain name to the working IP address/s
If any of your IP's come back online they are restored to the IP pool. This effectively and safely keeps your site online ? even if one of your web servers is down.
The average failure detection and recovery time with a system like this can be as low as 15 minutes. This time varies depending on the speed of your site and the nature of the failure and also how long other ISP's cache (save) your DNS information.
The time taken for other ISP's caching your information can be manipulated in the failover monitor by lowering the "time to live" (TTL) cache settings. These are the settings that other ISP's will use to determine how long to cache your DNS information.
Of course you must bear in mind the matter of how frequently data is synchronized between your website's servers. This will be the hosting company's responsibility, and this may become complicated where databases and user sessions are involved.
The very expensive hardware based failover monitoring systems that point a virtual IP address to other ISP's, while behind the scenes juggling a number of unique IP addresses on different servers, is of course the most 'elegant' solution to multi server hosting.
That way, the whole issue of ISP's caching your information does not come into play.
Therefore, for site's that need to have true 99.99995% uptime, without huge outlays of money, the technology is readily available and certain proprietory failure monitoring systems are now relatively cheap to apply.
About The Author
Godfrey Heron is the Website Manager of the Irieisle Multiple Domain Hosting Services company.Signup for your free trial, and host multiple web sites on one account: http://www.irieisle-online.com
![]() |
|
![]() |
|
![]() |
|
![]() |
So - you know shared hosting no longer cuts it,... Read More
Sooner or later, as everyone finds out, nothing in this... Read More
There are few things as critical to your e-business success... Read More
If you have ever used EBay then you know how... Read More
Deciding how to host your ecommerce Web site and what... Read More
First of all we must determine the meaning of the... Read More
Your new website is ready to upload, and now you... Read More
The BasicsSetting up a web hosting account for the first... Read More
A client of mine paid for a solo advert to... Read More
Most web site hosting services like the one you're probably... Read More
With plethora of hosting companies offering services, choosing a good... Read More
One of the most common concerns people have when deciding... Read More
Nowadays, anybody can afford to order a feature-packed web hosting... Read More
You took the leap. You set up a website to... Read More
When it comes to budget web hosting, there are a... Read More
Once you have a website you then need to think... Read More
Perhaps your web hosting company has a technical support group... Read More
Are you disgusted or disappointed with your current web host?... Read More
If you're in business, one of the most important things... Read More
Although we are aware of Linux adoption by large enterprises,... Read More
Starting out in any type of online marketing or Internet... Read More
A web host reseller account is a web hosting account... Read More
There is story of David and Goliath where Goliath would... Read More
Bandwidth in its simplest terms refers to the amount of... Read More
Virtually anyone with an email address knows what Spam is,... Read More
It's time to choose! Should you spend some money to... Read More
Ever heard the saying "Penny-wise and Dollar-foolish"?Well bargain priced website... Read More
The first questions you have to ask yourself are: how... Read More
When you study the really successful websites, you will quickly... Read More
For those of you with Web sites, you probably know... Read More
Bandwidth explained:Bandwidth is the amount of data transfer that you... Read More
If you're reading this article, you might be interested in... Read More
Most Internet service providers do not give you static IP... Read More
If you've ever browsed the World Wide Web and wondered... Read More
Many businesses, from one-man-bands to multi-national corporations, have a web-presence... Read More
Consider the following web hosting blunders and do not allow... Read More
Web Hosting ? Made Simple What is web hosting... Read More
The matter of choosing between the operating system (OS) running... Read More
1. The reliability of the service and their offers.A brand... Read More
Sooner or later, as everyone finds out, nothing in this... Read More
You're not alone! Many people are bound to the old... Read More
There is story of David and Goliath where Goliath would... Read More
There are so many hosting companies offering to host your... Read More
If your web site has outgrown its shared hosting solution,... Read More
If you're in business, one of the most important things... Read More
Chances are if you host multiple domains or websites you... Read More
Blogging is an abbreviation of "web-logging". The simplest definition of... Read More
Your new website is ready to upload, and now you... Read More
Whatever type of website you want to host, choosing the... Read More
There are many things to consider when setting up your... Read More
With plethora of hosting companies offering services, choosing a good... Read More
These days, web hosting companies are popping up faster than... Read More
What sort of web hosting options should you go for... Read More
If you're looking for a professionally designed web site at... Read More
Web hosting services play a vital part in your website's... Read More
You have carried out the hard part and that's creating... Read More
Managed hosting is a dedicated server that is accompanied by... Read More
"Bargains for sale, Unlimited Hosting for only a Dollar.""Get your... Read More
Web hosting can be an exciting business start up for... Read More
Finding a good and reliable web hosting company is like... Read More
It's tempting. There are so many companies offering cut-rate hosting... Read More
Well let me start this way, a lot of people... Read More
Deciding on the best web hosting company for a web... Read More
For those in the Internet business the availability of their... Read More
You're the webmaster of more than one website. You design... Read More
For the "big things" to be build it was certainly... Read More
Web Hosting |