Friday, July 11, 2008

Dude, Where's My Site?

Is the Internet open for business today or is it taking a little time off? Sometimes you gotta wonder. You enter a domain in your browser or click on a link and... nothing. To paraphrase the famous Dr. McCoy, "It's dead, Jim."

Or is it?

Can you really be sure that a website is down and that the problem isn't just your connection? Well, now you can. There's a new free online tool to do just that. It's called, appropriately enough, DownForEveryoneOrJustMe.com.

It's the brainchild of Twitter engineer Alex Payne, who heard the phrase "is it down for everyone or just me" so often that he decided to give people a way to find out. You just enter the URL of the site you're concerned about and click the "or just me" link or hit return. You'll find out immediately if it's you or them. Alex has pre-filled the entry box with Google.com in case you just want to bash your enter key and see if anything is running.

This all presupposes that you can get to the Internet at all. Seems like if you could get to DownForEveryoneOrJustMe.com that you could go to just about any website, anywhere. After all, it is the WORLD Wide Web.

Logical, yes. But wrong. The Internet Superhighway may be wide open and ready to take you anywhere you want to go. But it's to no avail if half the road signs are blank.

The culprit is DNS or the Domain Name System. This is the core service on the Web that equates domain names with IP addresses. Without DNS, you'd have to type a series of numbers into your browser to access a Web site. DNS service is normally invisible. But when it goes down, your browser has no idea where to go for the site you want. So it sits and spins until you get an error message.

Who runs this DNS service? Each Internet Service Provider or ISP has a DNS nameserver that works like a phone book to look up the IP addresses for domain names, as browsers request them. These nameservers are connected in a hierarchy of other nameservers that eventually lead back to a root name server that holds the master database of domains and addresses.

If your ISP's nameserver goes down for maintenance or just an electrical glitch reboot, you've got no access until it comes back. That's even if your broadband connection is working fine. A weird situation is when you try to access the DNS while the nameserver is coming back online. Some sites will work fine. Others are unreachable. That makes you think the entire Internet is down when it really is only you. That's you and your neighbors on the same ISP.

Another common situation is when you register a new domain name or switch hosting services. Your entry or change in the DNS doesn't happen instantly. It takes time for all those nameservers around the world to get the updates. This process, called propagation, can take up to 48 hours. Usually it's a lot faster. But if you happen to have an ISP with a slowpoke DNS nameserver, you'll just have to wait to see your new Web site or work on it.

I found a workaround to the situation by using a third-party service to check my new domain names and hosting to see if they were ready yet. AnyBrowser.com is a free online tool intended to let you see how your site looks in various browsers. But AnyBrowser.com has a different and generally much faster updating DNS than my ISP. Like DownForEveryoneOrJustMe.com, it will give you another means of verifying if your site is up or down. But AnyBrowser.com tools will also show you what your site looks like and whether you've entered your Meta tags correctly.

Another approach is to get yourself set up with two different broadband services, DSL and Satellite or Cable and T1. If they are completely unrelated, at least one should be running no matter what. If you can afford this arrangement, then you can say with confidence: ThatSiteIsDownBecauseItCouldNotPossiblyBeMe.



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