Web Hosting

When you begin to look for a company to host your website, other than the amount of space and bandwidth that is offered, a company will usually promote their web hosting uptime. Most web hosting companies offer an uptime guarantee to promote how well their service is.

Web hosting uptime is a measurement of the time a computer server has been running, the longer the web hosting uptime the better the service (usually). Uptime is important to not only web hosting companies, but to any person or company that has a website, because if a website is down it could hurt a personal company’s reputation as well as the reputation of the web hosting uptime guarantee. Web hosting companies strive for a 99.9% uptime, which means that there would be less then 2 minutes of downtime a day.

Factors that impact a web hosting uptime are sometime unavoidable, but many companies strive to prevent downtime. Downtime can be classified in three ways: planned downtime which is caused when a server is updated or upgraded, semi-planned downtime which is caused when software companies find a security breach and a patch must be put into place, and the worst is unplanned downtime which can be caused by an overloaded server, a software/hardware malfunction, or malicious software.

Uptime guarantees made by web hosting companies are based off of past information. Web hosting uptime can be monitored and maintained a few ways. There are services that provide 24/7 monitoring. Large web hosting companies have their own departments that monitor their servers. A loss in web hosting uptime can be prevented by having a redundant server to fall back on incase the primary server goes down. For a planned single server change this method may be practical for a larger company, but the costs implied for an additional server in a smaller company or providing this for multiple servers in larger companies can be impractical. Unplanned downtime would also keep this method from working well.

Some niceties that many websites provide is a friendly downtime message that will still allow the user know that the site is only temporarily down. Larger web hosting companies are able to provide a quicker return to normalcy to maintain their uptime guarantee, because they have staff readily available to respond to a downtime error quickly. Smaller companies may experience a longer downtime.

For consumers, researching web hosting uptime can prevent a package from being purchased from a web host that has a lot of downtime. There are websites that track a company’s web hosting uptime and provide reviews on the company freely for review. Other places to look for information are on forums either provided by the web hosting company or on web hosting review forums.

If your website does experience downtime you can contact the technical support or customer service department to see when your site will be restored. Understand that no web hosting company can have a 100% uptime guarantee. If your website experiences too much downtime switching to a different company with a higher and better web hosting uptime may be your only option.

Game servers are usually developed in a form of a standard component that can be found in many games that have a multiplayer option. After this kind of business became popular, hosting companies immediately responded to the growing demand and started offering dedicated servers for online gaming to both those who want to make business and to those who are simply enthusiastic. Generally game server hosting caters to two main groups of online games – those available from the main server, and those that operate through a series of distributed ones.

Centralized servers are mostly often used to host games that require these servers to be able to host thousands of users playing at the same time. The main server stores all the necessary data about the game environment and the cyber world is there 24 hours 7 days a week. The game goes on no matter if the user is online or offline. To participate in the game, a player usually needs special client software that connects to the main server. One of the most popular game using the technology of centralized servers is the World of Warcraft.

Another model is the distributed servers technology. This one is usually utilized by enthusiasts and small businesses. In this model the software is distributed onto several dedicated game servers. As an example, real-time strategies are usually based on this technology. They need frequent updates of the game world that is executed through messaging between users and servers. There should be a master server in this chain to control messaging between the whole bunch of distributed servers. Low latency and fast ping time – that is what needed for this model to be successful and ensure the fast speed of messages reaching the server and coming back to the user. Users usually choose servers with the best ping rates and connect to them to play online. That is why game server hosting companies connect their servers to the fastest networks. Security, operating system and applications tweaking and thorough configuration are also very important.

Hosting providers usually supply their clients with game server hosting services that include the most technologically advanced servers and network connections, very often with the preinstalled software to start online gaming business immediately. The most popular games using the technology of distributed servers are: Doom 3, Medal of Honor, Halo, Unreal Tournament, Counter Strike, Quake 3 etc.

Game server hosting providers are expected to significantly increase their revenue due to such rapid growth figures of online gaming. Many hosting companies have already build up a wide range of special game server hosting offers including even those for $30-40 a month. This is significantly cheaper than many low-performance dedicated servers.

Once you’ve chosen your domain name and got it registered, what’s your next step?

Your web host will give you the details you need to get your site up and running. This will include passwords to log into your website account, the paths to the directories where you need to upload your information, and most importantly the addresses of your domain name servers.

DNS servers are the link between your domain name (mydomain.com) and your IP address (a numbered address like 123.456.78.9. Every web server on the internet has a unique IP address.

If your website is hosted on a dedicated server, your IP address is unique to your website. Your website will respond whether someone types the domain name or the IP address into their browser.

Most websites are hosted on shared servers, however. What this means is that a single server hosts many websites, and each one shares the same IP address. If you enter the IP address of a shared server in your browser, it won’t display your website.

DNS is the “translation” layer between domain names and IP addresses that allows multiple sites on one server.

Configuring Your Website On DNS

When you register your domain name, it will be pointing to the DNS servers for your chosen registrar. Until you have a account set up with a hosting service, your domain will usually point to an error page or an “under construction” page.

Keep in mind that there’s no time limit between registering your domain and choosing a web host. Some people register domains and never actually get a website hosted on them.

If you’ve bought your domain with plans to use it, you’ll need to sign up for an account with a web host and upload your website’s files to their server.

The first step in making your website active is to change the DNS servers on file with your domain registrar to the ones that are given to you by your web host.

The DNS server information will look similar to this:

Primary Name Server: NS1.SOMEDOMAIN.COM (123.456.78.9) Secondary Name Server: NS2.SOMEDOMAIN.COM (123.456.7.89)

You’ll get this information from your hosting company when you sign up for a hosting account. If you can’t find this information, you’ll need to contact your web host to get it. Otherwise your website won’t be accessible from the internet.

Once you have this information from your host, you’ll need to change the settings on file with your registrar to the new addresses. If your domain name was included with the purchase of your hosting, the web host will normally update this information for you automatically.

Once the DNS servers are registered it can take up to 48 hours for your site to be accessible across the internet. This is because of the way the DNS system works.

The domain names and IP addresses are stored in a database that is distributed through thousands of computers around the world. Each computer keeps a small part of the database cached and if they get a request for an unknown domain, they have to forward that request to another computer until the information is found.

This database gets updated on a constant basis on each of these computers, but it can take some time for your new website’s information to spread throughout the world.

Your small business website needs to be hosted on a web server or simply a server (another name for computer) that is connected to the World Wide Web so that anyone can access your website.

Choosing a web hosting company for your small business website is easy if you follow the guide I have layout for you. Depending on the scale of your business, the type of business you run and your level of technical competency, there will always be a right hosting provider just for your business.

The general rule of thumb in choosing a web hosting provider boils down to:

Excellent Customer Support

Company Stability

Robust Datacenter

Affordability

Excellent Customer Support If all things being equal, I would rate customer support as my number 1 determining factor in choosing a web hosting provider. Relying on testimonials found on the provider’s site is a common approach to assess a company’s level of customer excellence but it is also quite an outdated one. After all it’s not uncommon for some providers to fake the testimonials. Instead I suggest you follow my way of assessing their customer support.

Sizing its level of customer support is sometimes as easy as finding out whether they have enough employees to support their level of business growth. You should look at the Customer to Employee ratio, CE ratio, as a benchmark.

For example, according to our records SiteSell Inc has approximately 15,000 customers and employs about 30 support staff, it has a CE ratio of 500 (15,000/30 = 500), you can expect a much higher level of customer satisfaction and a faster response time when compared to another provider who is serving 100,000 customers but only have 75 support staff. Their CE ratio would stand at approximately 1,333. Basically you should look for a professional hosting provider with a low CE ratio.

Getting As Close As You Can The other accurate way to assess the real status of its customer service is to get as close as you can to the company whenever possible via the following means:

Live Chat – Check to see if it’s 24/7. It helps to know that you can have your questions answered almost immediately with a live chat function. Test it out by answering some basic questions to see its response time and also test its level of technical competency. Not critical but it’s good to have.

Email – Send them a test mail to see how fast they respond, allowed up to 24 hours. Ask about anything but just do not be afraid to ask.

Number of Telephone Lines – Check to see if there are separate telephone lines for sales, customer service and technical support. I hate companies who use only 1 line to serve everyone. A professional small business hosting provider should have this in place. It is not uncommon for reputable providers to charge for telephone support.

Forum – The real condition of any web hosting company’s customer support is really found in its members forum if any. You will get a good dose of complains and praises but if the complains outnumber the compliments; it’s time to raise a red flag.

Company Stability A company’s stability can be measured by the length of time they have been in business, the number of customers they have served and are serving and lastly their financial standing.

Personally as a business owner myself, a web hosting company that has been around for at least 5 years would have weathered all sorts of ups and downs in the online world, and their chance of being around is much higher than a company that has been around for less than 1 year.

Financial Stability Though public listed web hosting providers have better financial transparency than the privately-owned ones, they are not necessary always in a better financial shape than them. Bottom line, you would host your small business with a company that you know is growing in their customer base. For example, Interland having been in business since 1995 is currently serving less than 200,000 websites and this number has been decreasing. It is most likely less profitable when compared to IPower in operation since 2001 and is serving over 400,000 websites as of this writing!

Another aspect of company stability lies in its ability to remain relevant in this highly competitive industry. For example, as the number of internet users increase and streaming multi-media becomes the norm, you want to place your business with a profitable web hosting company who is able to constantly improve on their offerings so that the performance of your website is able to keep up with visitors’ expectations.

Robust Datacenter Datacenters are where the web servers are resided on, and ultimately where your webpages will be accessed from. A strong and credible small business web hosting company would have the ability to own and managed their data centers or through colocation.

On one hand it might seem that is the best thing any decent web hosting company would do, but on the other hand, there seems to be a trend whereby the marketing and sale aspect of the hosting business has been outsourced to resellers.

The rationale behind this is quite simple, a web hosting company should focus on what it does best, i.e. make sure all servers are up and running. And a reseller role is to sell the hosting plans and is to focus entirely on doing just that without getting bogged down by technical issues.

Almost all the state of the art data centers should come equip with high level of security, uninterruptible power supplies and most importantly employs the latest technology to enable your website to be always up and running and is always accessible by high connectivity, i.e. fast access to your website.

Affordability Before I elaborate further, it’s important to establish that after qualifying a company with the above points, there is no such thing as the best small business web hosting plan, but only the right hosting plan for your business. This is probably the last thing you should look at before deciding on the hosting provider.

Generally there are 2 main types of hosting that are available for you to choose from. They are the Linux web hosting and windows web hosting. Within these 2 platforms there are also another few subcategories of web hosting types that you need to understand before you can finally decide on the right web hosting for your small business.

To continue reading this article, please visit my site Small-Business-Web-Hosting-Guide.com for a no-nonsense approach to assessing web hosting companies for small business owners.

Changing from one web host to another can become necessary if your website becomes popular and your current host can’t meet your needs for bandwidth, storage, etc. This can be especially true if your site is hosted on a free web host.

If a move become necessary, be sure to plan it carefully. The first step is to decide on a new hosting company, of course.

Once you have found a host that can meet all your needs, you need to move your site on to the new server. Before making any moves, be sure to back up your website from the old host.

If your website isn’t well structured and has been growing haphazardly, this is a good time to consider redesigning things. That could simply mean a new page design or it could mean redesigning your database and content storage.

For the first 48 hours after moving to a new host, you should use a redirect page on your old site, that automatically forwards people to the new one. This will ensure that your visitors will see the new site, even if its IP address hasn’t propogated yet.

It takes about 48 hours for a new website to get listed on most domain servers across the internet, so after that you should be fine.

A few more suggestions for an easy transition include:

1. Find out whether your new host is running on Unix or Windows and make sure it will be compatible with everything you’re moving from the old host.

2. Check to see how much storage you need for all your files and content on your current site, and make sure you get enough on the new host to give you room to grow.

3. Check to see what services your new host offers, and make sure anything you have been using on your current host (like autoresponders, mail forwarding, etc.) is available.

4. If your current website is created using Microsoft Frontpage, make sure your new host supports Frontpage extensions.

5. Check to see what your new host’s policy is for extra bandwidth, in case your site continues to get busier.

6. If the new host’s server is a shared server, check to make sure there are no adult sites hosted on the same system. They can get busy and cause all the other sites on the same server to slow down.

7. Check the review sites and forums for customer feedback about your new host before signing up. These are good indicators of the level of service you can expect.

Once you have your data uploaded to your new host, test your site to make sure it’s working properly. You should be able to preview your site before you fully switch your domain name to the new address.

If you are about to purchase web hosting, it is very likely that you will be using cPanel to manage your hosting. To get the most from your web hosting, you need to learn the workings of cPanel.

What Can Be Done with cPanel?

If your web hosting doesn’t offer shell access, cPanel will be the only way to manage your web hosting, cPanel is a web based server control software that allows you to do the following operations and a whole lot more. Common operations such as adding FTP users, creating databases, creating mail accounts and a multitude of other hosting operations can all be performed with cPanel.

Creating Mail Addresses

If you have the domain xyz.com and you would like to create a mail address called info@xyz.com, you can perform the following. Firstly click on the Mail tab from the front page. There you will see options to create, modify or delete mail accounts. If you to forward mail to an existing account here you can set an addres to forward to the account of your choosing. To read emails access the Webmail tab from the front page

Managing your domains

You may want more than a single address directed towards one web site, for example if you owned xyz.com and xyz.net, this can be achieved by using the Parked Domains tab, here you can type any address that you own to point to one of your web sites. If you hosting provider allows you to have more than one web site on your account, you can add domains via the Addon Domains tab. If you hosting provider supports the creation of sub domains you can create these via the Sub Domain tab.

FTP Options

You can create additional FTP users, set their access levels and other FTP related tasks using the FTP tab.

Database Tasks

To create a new database, or modify existing databases use the Database tab. Here you can perform all allowed database tasks, to perform more advanced database operations you will need to use phpMyAdmin, this can also be accessed from the Database tab.

Analyze The Logs

When running a web site you need to know what your visitors like, where they are coming from, which search engines are bringing the most visitors and all other data about them. Normally you will have access to the raw log files, but these are hard to analyze, to see data that is formatted about your visitors in an easy to read way go to Web/FTP Stats, here you will have the option to review your sites statistics using a variety of software such as Webalizer or AWStats.

Fantastico

Most if not all cPanel installations these days come with Fantastico which is an auto installer for many php based scripts. Fantastico can be used to install popular php scripts such as WordPress, Mambo, phpbb and many other php products. Using Fantastico is the easiest way to setup these php based scripts and will save you having to manually upload the scripts, and more often than not Fantastico will do all the configuration of the script for you which is a real time saver.

Final Words

cPanel is a very advanced application for configuring your hosting and learning all the tricks can take some time, but hopefully with this guide you will have the basics down and you can progress from here as your experience with web hosting increases.

What is Linux/Unix-based hosting?

It means hosting that is provided on Linux/Unix operating systems platforms. There isn’t much difference between these two types of operating systems because Linux/Unix is an improved version of Linux/Unix operating system. When just applying for web hosting companies for web hosting that is based on Linux operating system it doesn’t matter which one you are using on your computer as it is commensurable with any operating system.

Usability

Some years ago Linux operating system used to be available only for professionals and if you were not an experienced user you had no future with this OS. In the last couple of years the situation has changed. Providers have done their best to make users’ web sites administrating more comfortable and easier. In case you’re just a beginner you’ll find friendly control panels that include Web- interface. And if you are an experienced user you can control your site by means of shell.
Reliability

Experts claim that Unix-based platform is one of the most reliable ones but it will mainly depend on maintenance stuff professionalism. Thus quality and stability of Linux-based web hosting won’t depend on some sudden system bugs and the operating system consistency itself secures your web site operating dependability.
Functionality

In this area Linux differs the most from other popular platforms. It can handle a lot of processes that happen at the same time. This gives you a possibility to get more from the server.
What Scripting Languages Are Available For Unix?

Unix supports a wide variety of application languages, more than any other operating system. The most common applications of such kind include C, C++, Shell, Perl, Tcl, Python, Java and PHP.
What Databases Does Unix Support?

Databases available for Unix are mSQL and mySQL. The one you choose would depend on your own needs and your Host Provider’s offers. This is important for you to review when choosing a hosting company.
Cost

Linux operating system was developed by Linus Torvalds as an alternative to other operating systems and is being improved by many specialists all around the world. Most of its versions are free of charge. This circumstance makes Linux-based hosting much cheaper than any other. As for Linux versions they are sometimes called Linux Distributions. The most popular Distributions are RedHat and Mandrake. Which are easy to install have a lot of different utilities and suitable for any web hosting type.
Why choose Linux/Unix-based hosting?

So, as it was mentioned before using this platform is cheaper and more convenient than others. All existent scripts, like PHP, function best when using the Linux-based web hosting. Linux/Unix based web hosting upgrading possibilities increase when using Shell and Telnet access. The Linux/Unix-based platform is probably the most stable and reliable.

How much storage space and bandwidth will you need for your website? This is a question that you will need to answer before deciding on your web site hosting.

You’ll need to look at the content that you’ll be hosting on your site. Is it just plain text? Images? Audio and video files?

Plain text takes the least amount of space. Images take considerably more and audio and video files will need the most space. This applies to both the storage and the bandwidth.

Many web hosts offer what seems like a huge amount of storage space, assuming that you’ll never use it. If everyone hosting websites on their server were to use the maximum space allowed, the servers would likely not be able to handle it.

You’ll see a range of storage and bandwidth being offered. One host might be offering 1 gigabyte of storage while another could offer 500 megabytes at the same price. The quality of service is a key factor in choosing a web host, so don’t just look for the one with the biggest offer.

The rule of thumb in the hosting industry is that 2MB of storage is enough to host 10 web pages and 4 or 5 images. Using this as a guideline, you can determine how much space you’ll need to host your site.

You can calculate your bandwidth requirements in a similar way. Make sure you understand the difference between bandwidth and data transfer, however.

In non-technical terms, bandwidth is the diameter of a water pipe and data transfer is the amount of water that flows through it. If you’re likely to have a lot of data being transferred, you should look for high bandwidth plans.

If you choose a plan with high data transfer but low bandwidth, your site can slow to a crawl when it gets too many visitors. The amount of information you’re allowed to transfer is high enough, but the pipe it’s flowing through doesn’t allow enough to get through at once to keep up with all the requests.

The best way to manage your bandwidth and space is to keep your site as simple as possible. Don’t use large images – optimize them for viewing on the web which will decrease their size considerably.

If you’re not sure how to determine your needs, the better web hosting companies will be able to help you figure out which of their plans will best suit your website.

If you have a web site, chances are you hired someone to help you get it launched. If you did, you have three primary components under the umbrella of “a web site.” There is your domain name, also known as a “URL” or your web address. There is your web hosting – the space you rent on a server out there somewhere, to put your web site on. And then there is your web site itself, which is a combination of HTML files and images which are uploaded to that web hosting you rent.

The most cautious rule of thumb is that you should have three separate providers – a domain name registrar, a web hosting company, and a web site designer. The reason many web experts believe this is that if you have a problem with one, you still have control over the other two. For example, if your web hosting company causes you problems, you have your web content, and you have access to your domain, and you can easily shut off one hosting account, find another, and move your site. If your web designer goes bad, you can at least change access to your site, move it or provide the information to a new designer. Conversely, if you have all three components in one place, you run the risk of finding yourself without a web site, perhaps temporarily, or worst case, having to start from scratch.

Although I’m personally a believer in keeping it all separate, the majority of business people don’t think like that and a great many folks have gone for an “all in one” situation where the hosting, domain and web site are with one provider. Whatever your scenario is, there is one absolutely critical piece of information you should take from this article. You MUST have administrative control over all three components of your web presence: domain, hosting and content. You don’t have to DO anything with it – except print out the access information and stash it away. You can rely on someone to manage it all for you, like I do for most of my clients. But if you don’t have this information, you don’t really own your web site!

Even if you have a wonderful relationship with your service provider, stop and ask yourself the following:
Do you know the name of the domain registration company?
Do you have the username and password to access your domain account?
Are you certain that YOU are listed as the legal owner of the domain?
Do you know where your web site is hosted?
Do you have the “FTP” (this stands for file transfer protocol) username and password to get to your web site on the host server?

A frightening number of new clients come to me without this information, and very often, they’ve already run into trouble and need help. In some cases, they have had to start all over with a new web site. In one situation, a client almost lost her domain name because the “all in one” company she had paid for a web site had made themselves the legal owners of the domain!

Don’t wait until you have a problem – make sure YOU own your web site, right now.
Eileen Parzek is an award winning graphic designer and writer providing digital and print graphic design and web design services. Always found at the intersection of information, creativity and technology, her business, Business Design Studio (http://www.businessdesignstudio.com) helps small businesses make a big impression, increase their reach and grow.

After your account has been opened with your web host and you’ve set the DNS for your website (see Parts 1 and 2 for more information) you can start to upload your content. The most common way this is done is through FTP (File Transfer Protocol) software, but there are a few other options as well.

The FTP protocol lets you transfer data files from one computer to another. Your web hosting company will give you the information you need to connect to your site with FTP.

You normally would use software like WS_FTP or FileZilla to connect. Your FTP address will usually be ftp.yourdomain.com.

Your web host will also tell you where your files should be uploaded to on the server. There is usually a folder in the root directory of your website called public_html, www or something similar. This is where you need to store all your website files to make them accessible to the public on the internet.

You might have to adjust some settings in your FTP software to make the files upload properly. eg. If you’re running a firewall on your computer (or a hardware firewall) you may need to set the transfer method to “passive”. And if you’re using a proxy server, you’ll have to adjust those settings as well.

Files can be transferred with FTP in either ASCII or binary mode. If you use the wrong mode to transfer, you could end up with errors. Your FTP software might automatically determine which method to use by looking at the contents of the files you’re transferring. It’s possible that you might have to specify the mode manually, however.

Files that should be sent as ASCII include HTML (and variations like HTM, SHTML, etc.), TXT, ASP, JS, PHP, etc. Essentially, any file that you would open with a text editor should be transferred as ASCII.

Binary mode is used to transfer files such as graphics, compiled programs and media files.

With your FTP software, connect to your web server. Open the folder where you’re going to upload the files and then find the files on your computer that you’re going to send. You can transfer individual files or entire directories using FTP.

Most of the pages on your website can be named anything you want, but the home page or main page in any subdirectories should be named index.htm (or .html, .php, etc.) The name “index” tells the web server that this is the file that should be displayed by default.

So if someone goes to www.mydomain.com, what they’re actually going to see is www.mydomain.com/index.html, the web server just displays that file automatically so they don’t need to enter the “index.html” part.

If you don’t put an index file in each directory on your site, people might be able to browse the directory and see “behind the scenes” on your website. This can be a security issue in some cases, so it’s always a good idea to put an index page in each directory, even if it’s just a blank page.

What Other Ways Can You Upload Your Website?

FTP isn’t the only way to upload your web pages. Many web page creation programs have transferring built-in. Probably the most common example of this is Microsoft Frontpage. If your web host supports Frontpage, you can upload your site from within Frontpage itself and you don’t need to worry about how or where to transfer things. Frontpage takes care of everything for you.

Some web hosts also offer online site-builders. These builders work within your web browser and let you layout your web pages. Once your pages are finished, they automatically get saved to the appropriate location on your server.

These online site-builders are usually available through the control panel in your hosting account.

Unless overtly listed otherwise, most web hosting packages you’ll come across in your search are what are called shared hosting providers. What this means is that the server or servers that host your website are simultaneously hosting numerous other websites also. This gives you a discounted rate on web hosting services in exchange for tolerating certain technical constraints, like bandwidth, disk space, upload and download speeds, security and privacy, traffic, and probably the most notable restriction — total control.

If you want total control not only over the administration of your website but also over the very hardware and software used to run it, then you should be evaluating not shared hosting providers, but dedicated hosting providers. If your business is large enough or growing fast enough that it requires its own internet connection and server, you may need a dedicated web host.

What’s the downside to going with dedicated hosting providers? In a word: responsibility. In most areas of life, with total control comes total responsibility, and it’s no different with hosting providers. With a dedicated server, the onus is on you to buy, install, and maintain the actual equipment — the server itself — mounted in the dedicated hosting providers’ data center.

Fortunately, you still get the benefit of their presumably top-notch, around-the-clock security over the physical premises, but you remain fully responsible for the security of your cyber-premises. Likewise, dedicated hosting providers will ensure that the systems in the building are all provided with redundant uninterruptible and backup power and environmental controls, but it’s you who must keep your machines and cables maintained and functioning in this idyll environment.

How do you identify whether it’s time to switch from a shared host to a dedicated host? There are 3 main indicators to stay alert for:

Speed

If the traffic streaming through your shared server is slowing down your customers’ pace as they browse your site (or your employees, if an in-house site), it may simply be time to look for more unencumbered shared hosting. But if you’ve tried several shared hosting providers with the same results, then it may be time to remind yourself how impatient the average web surfer is. While you’re jumping from shared host to shared host trying to save a buck, your customers are jumping ship. Your ability to respond promptly and effectively to customer transactions and inquiries cannot be overemphasized either.

Reliability

The limits to your control are nowhere more apparent than in the areas of reliability and security. It’s not simply that problems can arise: problems do arise. It’s the nature of the biz. And if you don’t have unlimited access to your own operating system, software and database apps, etc., there’s not much you can do when one arises.

Customizability

If your company is growing fast, you’re going to be changing many aspects of your web presence along with it. You may regularly need to tweak your disk space and bandwidth and experiment with using different applications to better serve your changing needs. On a shared host, upgrading in such a way usually involves leaping from one “packageâ€� or “planâ€� to another. These packages are generally preset and may or may not serve your immediate needs. They may be riddled with programs you don’t yet need, for example, yet lack in the one singular program you do. Or the next leap up from your current plan has way more disk space and bandwidth than you need at the moment. With a dedicated server, you can make changes incrementally, step forward, step back, heck, step sideways if you need to — and when you need to.

In large part, it’s the size and growth rate of your business that will dictate whether you need a shared or dedicated host. Affordability and personal time commitment are nice secondary considerations, but if your business is booming, you would do it a great injustice to try and save on a few bucks and few extra hours per week of your time in exchange for slower and poorer quality of service for your customers.

By the same token, however, if your business is small enough to function quite smoothly on any of the shared hosting providers out there, don’t squander your precious capital on a dedicated server just so you can have total control. Because sometimes total control isn’t all it’s cracked up to be.

A high-volume site like Yahoo! knows that the actual quality of service any web server provides to end users basically depends on network-transfer speed and server response time. Network-transfer speed refers to the Internet-link bandwidth while server-response time depends upon resources including fast CPU, lots of RAM and good I/O performance. Once these resources are exhausted and the web-server is encountering heavy traffic, a
problem would surely arise.

Load Balancing

A problematic situation pertaining to difficulty in handling high volumes of incoming traffic can be solved either through installing more RAM on existing machines or replacing the CPU with a faster one. The use of faster or dedicated SCSI controllers and disks with shorter access time can also be done. Software can be tuned so that the operating system parameters and web server software can be adjusted to achieve better performance.

An alternative approach is to improve performance by increasing the number of web servers. This approach would attempt to distribute traffic unto a cluster of back-end web servers that need not be large-scale machines. Web server scalability is achieved when more servers are added to distribute the load among the group of servers or server cluster.

This is what load balancing is all about. It involves the fine tuning of a computer system, network or disk subsystem in order to more evenly distribute the data and/or processing across available resources. Load balancing is distributing, processing and communications activity evenly across a computer network so that no single device is overwhelmed. Busy websites usually use two or more web servers in a load balancing scheme so that when one server gets overwhelmed with requests, traffic is forwarded to another server with more capacity.

There are two probable reasons why a company could want to load balance traffic across firewalls. One is for purely technical reasons and the other is centered on winning business. The technical aspect should be quickly addressed as soon as funds and environment allow.

When there is only one web server responding to all incoming HTTP requests for a website, it may not be able to perform accordingly especially if the website has gained popularity. Loading of web pages will be very slow and some users would have to wait for their requests to be processed. It can come to a point where upgrading the server hardware is no longer cost effective due to the increased traffic and connections to a website.

Yahoo! was granted a patent from a filing done in 1999 regarding coordinating information between multiple servers that share information as well as servers that may cache some of the information. Load balancing devices are becoming very common in supporting high-traffic websites. These devices evolve as websites grow in terms of size, complexity and traffic flow.

The presence of multiple web servers in a server group requires that HTTP traffic be evenly distributed among the servers. These servers should appear as a single web server to the web client. The load balancer simply intercepts each request and redirects it to an available server in the server cluster.

Methods of Load Balancing

Load balancing can be achieved in a number of ways. Choice would depend on the individual requirement, available features, complexity of implementation and the cost. The user company would have to determine its circumstances to determine which option would work best.

The Round Robin DNS Load Balancing is one of the early adapted load balancing techniques. The built-in round robin feature of BIND of a DNS server facilitates cycling through the IP addresses corresponding to a group of servers in a cluster. It is a fairly simple and inexpensive method which is very easy to implement. However, its downside is that the DNS server does not have any knowledge of server availability thus may continually point to an unavailable server. It has the ability to differentiate by IP address but not by server port. There is also the possibility that the IP address is cached by other name servers which would result to request not being sent to the load balancing DNS server.

In Hardware Load Balancing, hardware load balances route TCP/IP packets to various servers in a cluster. This method is said to provide a powerful topology with high availability. It uses circuit level network gateway to route traffic. Its one downside is the higher cost incurred as compared to other methods.

The most commonly used method is Software Load Balancing. Load balancers often come as an integrated component of expensive web server and application server software packages. This method is more configurable based on requirements and can incorporate intelligent routing base on multiple input parameters. An additional hardware needs to be provided to isolate the load balancers.

Algorithm of Server Load Balancing

When HTTP requests are assigned to any server picked randomly among the group of servers, this is called random allocation. It is possible that one server may be assigned more requests than the others, but generally each server gets its share of the load. It can be very easy to implement but the risk of overloading one while under-utilizing another is big.

The IP sprayer assigns the requests to a list of the servers on a rotating basis when the round-robin allocation is used. The first request goes to a randomly picked server in a group so that the entire first request need not go to the same server especially if more than one IP sprayer is involved. The circular order is followed in redirecting the traffic for subsequent requests. The server which has been assigned a request moves to the end of the list to ensure that all servers are equally assigned. The allocation is much orderly than random but it may not be enough based on processing overhead required and when there are differences in server specification in a server group.

The shortcoming of the round-robin allocation has been eliminated by the weighted round-robin version. In this case, a server that is capable of handling twice as much load as the other can get a weight of two. This means that the IP sprayer will assign two requests to the powerful server as against one request assigned to the weaker one. This takes care of the capacity of the servers in the group. However, it does not consider the advanced load balancing requirements like processing time for individual request. An efficient load balancer should be capable of intelligent monitoring that would help it direct requests to the server that is more capable of handling them.

“There are three kinds of lies: lies, damn lies, and statistics.”

-Benjamin Disraeli, popularized by Mark Twain

Lies, Damn Lies and 99.9% Uptime
Statistics don’t lie outright. They just don’t tell the whole truth.

Suppose your hosting provider claims 99.9% uptime during the past month. This means all the accumulated downtime during the whole month was no more than 40 minutes. Sounds great, right?

The numbers don’t answer one important question: when did the downtime occur? What if you were down 40 minutes during your peak usage time on the busiest day of the week? Suddenly 99.9% of uptime doesn’t sound so great. That’s the whole truth often missing in uptime reports.

The All Important Monitoring Interval
Convinced you can do better than 99.9%, you search for another hosting provider. You finally settle on one that offers an additional “nine” or 99.99% uptime per month. No more than 4 minutes of downtime.

Before you get too excited, let’s see where that extra nine comes from by examining the concept of monitoring interval. The monitoring interval is how often your hosted server is checked to make sure everything is working A-OK. Think of it as the lines on a ruler. It’s going to be pretty hard to measure down to one eighth of an inch if your ruler only has one inch lines on it.

Suppose your application is monitored every 15 minutes. Now say your server is rebooted. If the monitor runs while the server is down, your server will show as down for 15 minutes, even though it only takes 3 minutes to reboot. If the monitor misses the reboot window, it won’t show as being down at all.

A provider that offers 99.99% must have a small enough monitoring interval that it can measure down to the nearest .01%. How small is that exactly? Let’s break it down using the shortest month:

28 days x 24 hours/day x 60 minutes/hour x .0001 = 4.03 minutes

A service provider must provide a monitoring interval of no more than 4 minutes to provide a 99.99% uptime guarantee.

Finally, what of 99.999%, the so-called “five nines” of uptime? Well, we would have to monitor every .4 minutes or every 24 seconds. With the reporting period increased to a year instead of a month, it’s possible to have accuracy up to five nines with a 5-minute monitoring interval. Trouble is, who wants to wait a whole year for a report?

The best reporting will include a combination of daily, weekly, monthly and yearly statistics for comparison.

What Do You Mean, Down?
Now that you understand what a monitoring interval is, this next one should be easy: what is the meaning of “down”? If your service provider is providing uptime, how do they decide when something is down? Are they simply doing a “ping” of the server? Or are they testing the application itself?

If “up” to them means your server is running, even though your application is really “down”, your uptime statistics take on a whole new meaning — or lack of meaning.

Also, who is the one actually doing the monitoring? Ideally, you’d like to have a third party monitoring service. That way you know your monitoring numbers are independently verified.

Availability From a Business Perspective
There is a better way. Instead of settling for the one-size-fits-all approach of “nines of uptime”, set your own availability goals. The key is to examine availability from a business perspective:

What are my business-critical periods?
How much downtime is acceptable during off hours?
What kind of monitoring interval is needed?
How do we know if the application is down?
Who is actually doing the monitoring?

Always make a distinction between business hours and after hours. You should have different availability requirements for each period, even if your application is used 24×7. Next, create your goal using words and whole numbers, not percentages. For example:

Zero downtime during business-critical periods.
No more than 2 unscheduled downtime incidents per month of no more than 5 minutes per incident during after hours periods.
No more than 1 scheduled maintenance period per month of no more than 30 minutes during after hours periods.
Monitoring interval of 5 minutes.
Monitor key aspects of the application, not the server.
Independent third-party monitoring from multiple locations.

After defining exactly what your availability goals are, you can now strive to achieve it. The difference now is that your goal is 100% achievable. That’s a statistic you can count on.

Glen Kendell is a network architect and owner of Release to Production. He publishes a monthly newsletter called In-Production: Achieving True High Availability.