heidi | (no subject)

People have been asking us on FA about DNS propagation, and here's the best explanation we could find (it comes from hitnet.com.

DNS Propagation is the process by which the computers on the Internet update their records (DNS tables) to reflect new domain names & site name(s). When your domain name has propagated throughout the Internet, your domain name can be accessed and recognized on the Internet.

The domain name system is a global network of servers that translate host names like [url]www.hitnet.com[/url] into numerical IP (Internet Protocol) addresses, like 63.126.62.11, which computers on the Net use to communicate with each other. Without DNS, we'd all be memorizing long numbers instead of intuitive URLs or email addresses. And that wouldn't be much fun, would it?

When you type in a URL, your browser sends a request to the closest name server. If that server has ever fielded a request for the same host name (within a time period set by the administrator to prevent passing old information), it will locate the information in its cache and reply.

If the name server is unfamiliar with the domain name, the resolver will attempt to "solve" the problem by asking a server farther up the tree. If that doesn't work, the second server will ask yet another - until it finds one that knows. (When a server can supply an answer without asking another, it's known as an authoritative server.)

Once the information is located, it's passed back to your browser, and you're sent on your merry way. Usually this process occurs quickly, but occasionally it can take an excruciatingly long time (like 15 seconds). In the worst cases, you'll get a dialog box that says the domain name doesn't exist - even though you know damn well it does.

This happens because the authoritative server is slow replying to the first, and your computer gets tired of waiting so it times-out (drops the connection). But if you try again, there's a good chance it will work, because the authoritative server has had enough time to reply, and your name server has stored the information in its cache.