* Round-robin: Each node gets a request sent to it "in turn". So, node1 gets a request, then node2 again, then node1, then node2 again. * Least Active: Whichever node shows to have lowest number of current connects gets new connects sent to it. This is good to help keep load balanced between server nodes. * Fastest Reply: Whichever node replies faster is one that gets new requests. This is also a good option - especially if there are nodes that might not be "equal" in performance. If one performs much better than other, why not send more requests there?

In any of these scenarios switch will also detect if a node were to fail. So, if svr1.orcsweb.com was taken offline for maintenance - or it had a critical failure - switch would detect that and only send traffic to svr2.orcsweb.com. And since clients always access site via main URL (not node names) they have no idea that one of nodes is down - application continues to serve client requests seamlessly.

Besides high-availability (continuing to satisfy requests during a failure), a webfarm also gives an application a higher level of scalability - ability to handle more and more load. If load increased on application to point where performance started to degrade, more nodes could be added to webfarm (again, without clients noticing), giving ability to handle potentially unlimited levels of traffic (just keep adding nodes!).

Of course there are a lot of factors surrounding proper support of a webfarm - switches, fail over between switches (don't let switch be a single point-of-failure!), replication of content, synchronization of server changes, synchronization of application changes, etc, etc.. But a good system administrator (or experienced hosting company) can help address all of these issues for you.

By way, I need to slip in a plug for a related service we offer :-) Webfarm hosting starting as low as $199/month! Check it out at: http://www.orcsweb.com/WebFarm.aspx

Hopefully this has been a good introduction to webfarms for you, and hopefully I've properly communicated enough of benefits for you to consider this as a hosting option for yourself. With rates now down to affordable levels - why not get this additional layer of protection?

Happy hosting!

~Brad

Brad Kingsley is President and Founder of ORCS Web, Inc. - a company that provides managed hosting services for clients who develop and deploy their applications on Microsoft Windows platforms.

5. Backups: Pretty self explanatory, but make sure that your host is backing up your data each night, and ideally provides a way for you to back it up on your own. Whenever you are going to make significant changes to your site, make a backup, and be sure to always keep a copy of your site on your local PC. I can’t tell you number of people I’ve spoken to who didn’t have a local copy of their site, and lost their site on hosts server for whatever reason.

There are also some subjective aspects to choosing a host. These are types of requirements which are based on your personal preferences and needs.

1. Your Market: Many hosts choose to focus on specialized markets, either because of personal interest, or a specialized skill set. For example, if you are looking to host a church web site, you may look for a host which focuses exclusively on churches. They are probably better suited to address your specific content needs. Keep in mind though, that you should not expect to give up on items above for subjective requirements. A church focused web host is useless if they can’t keep your site up and running.

2. Hosting Plans: With cost of hardware and network connectivity coming down every day hosts are increasingly offering more and more features. The bottom line, and something that all hosts know, is that 99% of customers will not use even 1% of what they are allocated, so don’t over emphasize features you don’t care about. Spend some time determining what you truly need for your site and then look for a host that meets those needs. If your site is 10 MB, does it really matter that hosting plan includes 2000 MB?

3. Community: If you are type of person who likes to interact with your fellow webmasters, you will probably prefer a host which offers an online forum for interacting with other customers. This gives you a great place to ask questions, read announcements, and discuss features with people who are with same host as you.

The list of considerations could go on, but key is to find a quality host which meets needs of your site. To that end, I recommend documenting your needs BEFORE you begin looking for a host. Estimate your space and bandwidth requirements, determine what features you need, and look for a host which meets your needs at a price that meets your budget.