Fun with DNS: Three Useful Commands
The DNS is a distributed, hierarchical database where authority flows from the top (or root) of the hierarchy downward.
When thinking of the structure of the DNS, imagine an inverted tree. Each branch of the tree is within a zone of authority; however, multiple branches of the tree can be within a single zone.
The software (Bind being the most common) that stores domain name information is called a domain name server. A single name server can be authoritative for multiple zones. All zones have a primary master and a secondary master name server that provides authoritative responses for their zones.
If you query a name server not authoritative for a particular zone, that name server will most likely have up-to-date information. This is because zone information propagates throughout the Internet at regular intervals, and name servers cache zone information for which they are not authoritative.
There are three crucial commands that can put all the DNS information you need at your fingertips. The way to use this article is to try each of the commands listed on a domain name, so you can see what the output looks like. Learn by doing!
Zone file database records divide DNS information into three primary types: NS (Name Server) records, MX (Mail Exchange) records, and A (Address) records. NS records indicate the name servers. MX records indicate the hosts that handle e-mail delivery; the priority (pri) number indicates the order in which mail servers are used, with the lowest number receiving the highest priority. The A (Address) records map hostnames to IP addresses, the real names of machines.
This is the simplest of the DNS commands. It is a quick way to determine the IP address of a hostname:
: host www.your-domain-name.com
The -a option will return all of the DNS information in verbose format.
: host -a www.your-domain-name.com
Now that you know the IP address for www.your-domain-name.com, try a reverse lookup.
: host IP-ADDRESS
dig (domain information groper)
This command gathers and returns DNS information in a format the name server can use directly. You will find it easy to query specific name servers with dig.
You can quickly determine the Name servers of your host or any other host:
: dig ns your-host.com
Then you check your (or another) website against the host's name servers:
: dig www.your-domain-name.com @ns.your-host.com
Dig can provide output that is in the same format as the zone file itself. Here is how to get the whole zone file:
: dig any your-domain-name.com
Here are the most useful dig query types: dig any (gathers all DNS information), dig ns (gathers name server information), dig mx (gathers mail exchanger information) and dig a (gathers network address information).
The dig command can also do reverse lookups with output formatted for the zone file:
: dig -x IP-Address
You can use this tool as a single line command, or you can use it interactively, which distinguishes it from the other DNS commands. Once you have started nslookup, type set all to list the default options. As with dig you can choose the server (name server) you want to query, and you can decide the type of DNS information on which to focus.
Just as you can issue commands to nslookup interactively, you can also change the initial defaults by starting a .nslookuprc file. The format of the .nslookup is one command per line:
These three commands can provide you with most of the information you need about your domain names. They are powerful tools, and this article should provide you enough information to get started or offer a quick refresher if you already use these commands.
About the Author:
Dan Forootan founded EZ Publishing, Inc. in 1998. EZ Publishing's Small Business Web Hosting provides the essential tools for using the Web as a marketing tool. The package includes web hosting, the StreamSend permission-based email marketing solution. Please email questions or comments about this article to firstname.lastname@example.org. Thank you.
Sell Web Hosting for Fun and Profit
The market is good for new Web hosting companies. According to Forrester Research, there is now "positive - if modest - growth for Web hosting and managed IT services, at both the enterprise and SMB levels."
Setting Up Your First Web Hosting Account
Bound To Your Old Expensive Web Host by Fear?
You're not alone! Many people are bound to the old web host they've used for years because they're afraid of the hassle of switching. Customers will pay rates three or four or even ten times greater than what they have to, just because they're terrified that switching will be too complicated or that they'll end up losing their site altogether.
Adult Web Hosting: The All You Need To Know
What sort of web hosting options should you go for if you want to host an adult website? You need to remember that this is the most critical aspect of your adult website. Facts like shared or dedicated adult web hosting, the maximum allowed bandwidth, the average uptime of the server and the server space should be critically taken into consideration while researching for your adult web host.
Cheap Web Hosting ? Choose The Right Company
You have carried out the hard part and that's creating the web site. The next step is to get it hosted as to allow the public find your site. So why do so many first time web host seekers fall into the trap of a bad web host company? Well there are a number of factors to consider and none bigger than the price. We all want cheap web hosting but unfortunately price is not always what you should go for.
Changing to a New Host? No More Worries!
John's online business is expanding. His customers are increasing day by day. However, he feels very frustrated at the moment as he finds his website is 'down' about every 4th day. Whenever he calls up the support team of his web host, he gets the same old answer that his problem will be rectified soon. If the problems do persist it will surely hamper his business. He has been with his present hosting provider for the last year but now he feels he has to find a new web host as soon as possible because his present hosting package is also not able to meet up with his growing demands. This is not a one-off occurrence that has happened only to John, it happens with many people like him. Changing the web host might become a cumbersome task if John and other people like him don't know the correct procedure of doing it. So, let's have a look at the following easy and simple steps:
Choose A Host That Matches Your Home Business Needs
With plethora of hosting companies offering services, choosing a good web host seems an intimidating task. The technical jargon is hard to decipher and that makes it difficult further. It is better to prepare beforehand and then search for offers rather than acting otherwise.
4 Tips to Find the Web Host That?s Right For You
Choosing to make a web site is a very big decision. However, even more important than deciding to make the website itself, is choosing your web host. There are many web hosts out there, and so it is very difficult to find the web host that's right for you. In order to find the best web host, it is important to find as many options as possible, and have a clear idea of what you want out of your web host. Following these four tips will make your search for a solid web host a lot easier.
Website Sitebuilders: Easy to use Website builders Come with a Price
Professional web designers don't come cheap. A good web designer can easily charge you $1000 or more for a five page website. This high cost leads many people to tackle web design for themselves. How hard can it be? Get yourself an HTML editor, throw up a website and voila! Your website is live right? Wrong! There is a lot of knowledge you need to develop before you can get your self made website onto the internet.
Web Site Hosting For Your Business ? Free or Paid?
It's time to choose! Should you spend some money to get a web hosting solution for your business or get one for free?
Advanced Hosting for the Mission Critical Web Presence
As companies that conduct their business online have proliferated, hosting of those websites that provide the primary point of contact for transaction of business has become highly mission critical; having these sites go offline or perform poorly not only loses revenue but also detracts from the company's image and loses customer loyalty.
How to Start Your Own Hosting Services
If your like many another webmasters you might be thinking of starting a web hosting company. But where do you start? And more importantly, what do you need to know? Well, in this article I will show the basic things that you will need in order to succeed as a web hosting provider.
Avoid Getting Ripped Off By A Hosting Company
Chances are if you host multiple domains or websites you are spending too much money at your current hosting provider. Other hosting companies increase their profits by forcing you to create an additional hosting account every time you want to host a new domain or website. Let's say you have five (5) websites and they each cost you $10.00 a month. It is obvious you are spending $50 a month to host those five (5) websites, but did you know that you are getting ripped off?
How to Find Good Web Hosting for Your Site!
When building your first site the main things that you will probably think about is what types of content you will be adding to your site, how you are going to get visitors to your site and how you are going to generate good revenue from your site.
Buyer Beware: Web Hosting, Registration, and Site Building All in One Package Nightmares
Starting out in any type of online marketing or Internet business can be confusing and overwhelming. There are so many different aspects of a start-up: domain name registration and purchase, Web site host purchasing, and of course, the "building" of the Web site itself. This leaves many consumers looking for an easier way to purchase everything in one place, both to save money and to save time.
How to Choose a Hosting Web Package Cheap
If you're looking for a hosting web package cheap there are many things to consider. To find a hosting web package cheap you really need to do your homework and search the internet for the right host for you. But beware, just because a company might offer a hosting web package cheap you really need to look at what the package offers.
Choosing The Wrong Server Will Literally Make Or Break You
Choosing the right web server will be one of the most important decisions you will ever make with your online business. Why? Because the web server you choose will literally make or break your online business.
Server Host: Where Does My Web Page Go?
For those of you who don't really understand where or how your web page is sitting on your hosting sever, this is a basic over view of how it works.
Steps to Becoming a Web Host Reseller
You've decided to get a reseller web hosting account to resell web space. What now? Here's a step-by-step guide.
Web Site Design and Hosting
If you're looking for a professionally designed web site at cheap, bargain basement prices, you may find it as close as your web hosting provider. Many companies that host web sites also offer web design services to their customers at low prices. Some of the best deals to look out for are:
|© Athifea Distribution LLC - 2013|