DNS propagation explained - or why you have to wait the 72 hours
So you found a perfect domain name that was not already taken,
figured out how to register it, paid for hosting (leasing space
to store all the files that will be publicly accessed as web
pages) with a WHP - aka Web Hosting Provider (such as
bsleek.com) and even uploaded your website to the WHP's servers,
or had a professional design firm create a web site for you.
Alas, it looks like the results of your hard work, of your money
spending and of the headaches you got from trying to make sense
of all the technobabble were in vain? Why can't you see your
website instantly - after all, isn't this the promise of the
e-commerce age?? Hey, when they took your credit card payment,
that went pretty fast!! Is it that nobody really cares about
customer service anymore? And what is this "propagation"
nonsense those techies are trying to bamboozle you with?
Is your new Web Host Provider a lemon? Did you make a big
mistake choosing it??
All this has to be very frustrating, unless you understand
exactly how things work. Over the next few paragraphs, I will
try to demystify the DNS propagation process, by telling you in
plain English, what DNS propagation is, how it works, and why is
it that the only thing we can do to speed the process up is....
wait.
DNS stands for Domain Name Server. I know the word Server is
intimidating and you are thinking "oh sure, another article
written in technicalese language". Think of a server as a
regular computer, like the one you are using now to read this.
That's right! Your beloved computer can be a server too. We call
a computer a server when that machine is up and running and
providing a service ("serving" something, whether a web page, a
text document, etc.)
With the language barrier lowered, I will tell you that DNS can
be tricky, especially when first registering a domain name or
transferring your website to a web hosting provider. The
strangest things can happen that would lead you to believe that
your new web hosting provider is at fault.
99.99% of the time the Web Hosting Provider is not to blame and
I will explain why.
There are a number of things involved in DNS that I will
familiarize you with. Sorry, but it has to be done. Again, like
everything else in life, once you understand how things work,
things will look much brighter.
Things you need to hear about are:
- IP Addresses - Service Providers - Domain Names - Domain Name
Registrars - DNS - The Propagation Process
1. IP Addresses
Our computers talk to each other by identifying themselves using
numerical addresses much like the address on your home or for
your telephone. When one computer wants to speak to another
computer, it all boils down to an address or what we call an "IP
Address".
Here is an example: 64.247.43.26
As you would imagine, the number of possible addresses, while
immense to the untrained eye, is actually limited and we are
almost on the verge of exhausting all the numbers.... Here's a
piece of trivia for all interested in cool facts: Typically,
service providers (see below) receive thousands of IP addresses
to be used on their networks. IP addresses in the United States
are assigned by ARIN, the American Registry for Internet
Numbers. They are the assigned numbers authority and they
control who gets IP addresses in the US.
2. Service Providers
The service providers will use IP addresses to identify their
network equipment so that they can conduct business on the
internet.
There are many different types of service providers but for the
purpose of this article, I will only discuss two of them.
The ISP (or Internet Service Provider) is the company that
provides you with access to the internet. Without them, you
would not be able to send email or surf the world wide web. When
you connect to your ISP, they will assign your computer one of
their IP addresses. This IP address will be used to identify
your computer while you are connected to the internet.
The WHP (or Web Host Provider, such as bsleek.com) is a company
that provides a means for individuals or businesses to publish a
website on the internet. When the website is published, it is
placed on a special computer known as a server that is connected
to the internet via a high-speed connection. The WHP has already
assigned this server one of their IP addresses.
Now, let's summarize what we have learned so far by looking at a
typical internet users experience:
Let's say that you want to surf your newly published website.
You connect to the internet and your computer gets an IP address
(much like a phone number, a license plate, etc) from your ISP.
You then open up your web browser and type in your website's
domain name: yourdomain.com.
Then you hit enter. Your computer sends a request. That request
is blasted across the internet jumping through routers and
gateways, across wires and beamed to satellites and back down to
Earth again. After traveling several thousand miles in just a
few milliseconds, it finally arrives at your WHP's web server
because it contains the IP address of the computer you are
looking for.
The server then responds by sending a copy of the website's home
page back to your computer because it knows the IP address of
the computer that made the request. You are now looking at your
published home page in merely a few seconds and being proud of
the pretty colors you picked for your menu buttons.
How did this all happen? Read on:
3. Domain Names.
A domain name is what you typically enter into your web browser
when you want to visit a website. We also use them when sending
email.
Website: www.yourdomain.com / Email: user@yourdomain.com
Domain names provide a fast and convenient way of reaching our
favorite websites and sending email to each other. It is easy to
remember the name of a friend's website or a company that you
like to shop with rather than trying to remember a number like:
64.247.43.26
What are we missing here? The mechanism that translates numbers
into names (that is, IP addresses into domain names) and vice
versa. Suspense....
4. Domain Name Registrar
If you want to have your own domain name you will need to
register one through a company called a Domain Name Registrar.
The domain registrar has tools that allow you to search for and
register an available domain of your choosing. The registrar is
more or less at the top of the whole naming scheme chain.
If you were able to read this far and even stay focus,
congratulations - you ar a very determined individual. And now,
as a reward for reading this much of my article, I will talk
about... DNS, which is the topic you came here to read about in
the first place.
5. DNS
DNS is a software program that runs on a dedicated computer
known as a DNS server. DNS serves two primary functions:
1) To translate domain names into IP addresses.
It's much easier to remember a domain like mydomain.com than a
sixteen digit number like 64.247.43.26. DNS servers make
translating or "Resolving" this information fast and seamless.
When your computer needs to know the IP address for
yourdomain.com it asks a DNS server (usually the one provided by
your ISP.)
2) To act as authority for designated domain names.
Wherever you decide to host your website, the network you are on
must have its own DNS servers. In fact, it is an industry-wide
standard to have at least two DNS servers or more. These servers
will act as the authority for your domain name because your
network provider will put a special entry in their DNS server as
it relates to your domain name that says: YOU ARE HERE!
Technically this is known as an "A" record for "Authority".
There are literally hundreds of thousands of these DNS machines
world wide. They ARE the yellow pages of the internet and they
contain information about your domain name. Keep in mind that no
single DNS server holds all the domain names for the internet;
they only hold the names that they are responsible for, and a
few pointers to find the rest.
Some DNS servers strictly store names while others are doing the
work of providing lookup services for computers that need to
look up names. Many DNS servers do both. Technically, the server
that is responsible for a particular domain is called the
"Authority". Remember the "A" record?
There are a few pieces of crucial information stored in a DNS
server with regard to your domain name. This information as a
whole is known as your "DNS Record". In it you can find a
variety of other pieces of information (or records) about your
domain name. For the purposes of not altering your sanity, in
this article I will focus only on the domain name, the 'A'
record (or your WHP's DNS servers).
6. The Propagation Process
As I said before, your domain registrar is the one responsible
for publishing your domain name at the very first (called root)
DNS level. When it is published, it is placed into a directory
that is broadcast out to primary DNS servers around the world.
The primary DNS servers broadcast out to secondary DNS servers
and so on and so forth.
This process is known as propagation and it can take upwards of
72 hours to complete. Propagation refers to the amount of time
it takes for all the DNS servers everywhere around the world to
recognize the fact that either a new domain is being registered,
a domain name has been changed, or that the authority for that
domain has changed.
Other reasons why it takes so long is obviously the size of our
planet and the total number of DNS servers that require updated
information. DNS servers are always updating themselves and
changing dynamically during the course of any given day. When or
why one DNS server will receive updated information before
another is a complete mystery - really!
In most cases, your DNS propagation will complete well within
the 72 hour period but you can't be sure that everything is fine
until you wait out the 72 hours! Once propagation is complete,
anyone, anywhere on the internet should be able to visit your
hosted website.
During that time you may experience strange occurrences. This is
because not every DNS server that needs to know, knows about
your domain name. Take your ISP for example. They use two DNS
servers, well, 24 hours after making your nameserver changes,
only one of your ISP's DNS servers might receive the update
regarding your domain name and the other might not.
If only one of these servers can resolve your domain to an IP
address and the other can not, what you will experience would be
as though your website was going up and down. One moment it is
there, the next it is not.
Here is another example:
A friend of yours can see your new website and you can not. This
is most likely because his ISP's DNS servers are able to get the
information at that time, where your ISP's DNS servers can
not.and wait another 72 hours. Ouch!
Here is a neat one:
You are transferring your hosting to a new WHP. During
propagation you are working on development of some pages in your
website. But you notice that when trying to view your most
recent changes, they appear and then vanish or they don't appear
at all.
Think about the load-balancing DNS servers again. One server has
information about your OLD WHP and the other has information
about your NEW WHP! This can be a weird experience and may take
some time to figure out. What you really need to do is WAIT OUT
THE 72 HOURS!
You see, if you avoid making changes to your website during a
transfer/propagation period, you will always have a consistent
functional website available to your visitors. They won't know
that you have switched WHP's because as far as they can tell,
they are just browsing your website. They won't realize that you
are in a state of propagation and that from one minute to the
next, they are potentially browsing your site from two different
WHPs.
All of these occurrences are very common and each one of them
will result in a phone call to the WHP asking why the server is
going up and down. In reality the server is fine and your WSP is
one of the finest. The problem is that the domain owner has not
let 72 hours pass by, after which these and other similar
problems will have vanished.
So as you can see, your Web Service Provider is not at fault,
you just must have patience and wait the full three days before
you can try to determine if your website is experiencing a
problem or not.