In the last few weeks, I have been seeing many businesses struggling with DNS. Yes, a foreign term, only known to those techies. Here is a simple explanation of what it is and what it does.
What is DNS?
DNS, or Domain Name System, is the magic that translates human talk into computer talk out on the Internet. Liken it to a phonebook. You want to call Joe Smith. You pick up the phonebook, find Joe Smith, and dial his number. You wouldn’t know Joe Smith’s number unless you already knew it, he told you, or you found it in the phonebook. DNS is just like this. I want to call google.com. I tell my computer that, it goes and finds the “phone number” of google.com in the “phonebook,” and sends me right to their computer.
Why is it important?
First of all, without DNS, you would have to know a 12-digit number to access an internet site. It would take time, and you would have to “look it up.” Plus, what happens if Joe Smith changes his phone number? You would get a “line disconnected” message. Well, DNS has solved that problem. If google.com has changed its number from 18.104.22.168 to 22.214.171.124, they simply point google.com to that new number. Problem solved!
Second, and almost just as important, it provides the behind-the-scenes email structure. DNS tells an email message where to go. An email server looks to DNS to find that part after the ‘@’ sign (ex. [email protected]). And in recent years, it has been extended to provide some spam filtering ability as well. It tells other servers that if the message doesn’t come from me, and me only, dump that message in the trash.
Now, DNS is almost infinite in uses. It can help verify you own a website. It can help get you setup with email, using auto-discover on your computer or phone.
Can it cause problems?
DNS can cause all sorts of problems. It seems to be one thing that is not always understood completely. First, this DNS “phonebook” can be found in a bunch of different places. If you are looking at an old phonebook, things are not going to work. Here is how a typical DNS query would work:
1. Your computer looks to itself to see if it knows.
2. Your computer looks to your local DNS server, which typical is a server at your company or a router in your house.
3. If they don’t know where to go, it will go out to your internet provider’s DNS servers.
4. And last, if it still doesn’t know, it goes to “root servers,” or basically the last resort.
If none of these know what you are looking for, that is when you get the “Webpage cannot be displayed” or “server not found.” It can also be a problem if someone left some old information in any of those spots. If I once owned google.com and had it on my computer, if I don’t remove those old records, it will not work, because I don’t own it anymore.
What can be done about it?
Always remember, that at anytime you as a business are moving to a new email provider or website hosting company, have your previous provider remove all those old records.
Because it is such a specialized and complicated system, look for a service provider, like Firebytes, to review your records and make sure everything is flowing the way it should.