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
maide service in Lincolnshire ..You must have done all the hard works for developing... Read More
When you study the really successful websites, you will quickly... Read More
Choosing a budget web hosting company can be overwhelming. In... Read More
Consider the following web hosting blunders and do not allow... Read More
If you're looking for a professionally designed web site at... Read More
After the dot.com bubble burst a few years back I... Read More
Moving a web site to a new host is not... Read More
Some folks classify low cost web hosting on the same... Read More
These searchers are looking for a hosting company in a... Read More
With so many web hosting companies competing for your web... Read More
Ever heard the saying "Penny-wise and Dollar-foolish"?Well bargain priced website... Read More
"Unmanaged dedicated servers" - this is a pretty uninviting term... Read More
We often see server uptime statistics when looking for hosting... Read More
If you've ever browsed the World Wide Web and wondered... Read More
1. The reputation of the web hosting company.Most web hosting... Read More
In the first case the customer is really looking for... Read More
Are you disgusted or disappointed with your current web host?... Read More
Most Internet service providers do not give you static IP... Read More
If you've got or are considering a web hosting account... Read More
Web hosting can be an exciting business start up for... Read More
Well? you've purchased a domain name? created a pretty design?... Read More
Some web hosts are offering more than others for the... Read More
Chances are if you host multiple domains or websites you... Read More
Bandwidth in its simplest terms refers to the amount of... Read More
For a website to appear on the Internet, you require... Read More
cleaning lady near Deerfield ..You took the leap. You set up a website to... Read More
Well let me start this way, a lot of people... Read More
Business web hosting is what you need. You have a... Read More
If you are anything like me, you'd probably like to... Read More
For those of you with Web sites, you probably know... Read More
Most Internet service providers do not give you static IP... Read More
These searchers are looking for a hosting company in a... Read More
"Bargains for sale, Unlimited Hosting for only a Dollar.""Get your... Read More
Overselling is a big trend in the web-hosting world at... Read More
You've made your decision to move from your website from... Read More
How To Select A Web Hosting CompanyWhen starting out, it... Read More
A client of mine paid for a solo advert to... Read More
If you're creating a community web site or a business... Read More
Many businesses, from one-man-bands to multi-national corporations, have a web-presence... Read More
Many business owners find themselves in a quandary over the... Read More
After the dot.com bubble burst a few years back I... Read More
All the good ones are taken. The really good ones,... Read More
Spam is a real problem today. Forged email is a... Read More
This article describes the technology behind multiple server hosting and... Read More
If there's one thing that people love it is a... Read More
Personal Computers, Servers Or ISP?You need a server to host... Read More
With a little advanced planning, moving your domain to a... Read More
A few time ago appeared a lot disagreements between opinions... Read More
Finding a good and reliable web hosting company is like... Read More
If you're about to set up your first web site... Read More
Web Hosting |