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The ins and outs of DNS and how it effects your
domain:
Understanding DNS and Name Servers:
This is an area, which
causes a great deal of confusion amongst both
webmasters and end user hosting. Before we go any
further, let's look at this quick analogy: DNS can
be considered something similar to that of a phone
book. When you move from one location to another,
your last name stays the same, but your phone number
may change. In order to point your name to the new
phone number, you must contact the telephone service
provider, which will assign you the new phone
number. In addition, they update all directory
information data basis to reflect you as pointing to
this new phone number.
What is DNS?
DNS stands for "Domain Name Server." The domain name
server acts like a large telephone directory in that
it's the master database, which associates a domain
name such as (http://www.mydomain.com) with the
appropriate IP number. Consider the IP number
something similar to a phone number: When someone
calls
http://www.RegistrarHost.biz/, your ISP looks at the
DNS server, and asks "how do I contact RegistrarHost?" The
DNS server responds, it can be found at: 69.72.192.62.
As the Internet understands it, this can be
considered the phone number for the server, which
houses the http://www.RegistrarHost.biz web site.
Where are all of the
DNS records kept?
This is slightly more complicated, but for the
purpose of this overview, we'll try to keep it as
general as possible. There are 2 basic places DNS
records reside:
International Root name servers (13 exist throughout
the world)
Your domain registrar, where your current DNS
settings reside.
When you register/purchase your domain name on a
particular "registrars name server", your DNS
settings are kept on their server, and in most cases
point your domain to the Name Server of your hosting
provider. This Name Server is where the IP number
(currently associated with your domain name)
resides.
The entire hierarchy is somewhat involved, but in
short, the world Root Name Servers can be considered
the master listing of all DNS records, and there are
currently 13 of them in the world. These name
servers are where all the master DNS records are
kept. The DNS server of your ISP will typically
query the Root Name Servers once every 24-hours.
This is how they update all of their DNS tables,
which in turn, resolve www requests to the IP number
of the server they reside on.
Changing your Name
Server settings, so your domain points to your
RegistrarHost account:
Your "Name Server Settings" must be updated to point
to your account on RegistrarHost. You originally purchased
your domain name from a registrar, and this
registrar is where your current DNS settings reside.
That is, unless you transferred your domain name to
an alternate registrar, in which case, you would
control your DNS settings from there.
The "Register" your domain resides on, communicates
your 'current' DNS settings with the International
Root name servers, which is turn share this
information with ISP's, routers, and cache engines
around the world. In essence, it's like a worldwide
directory that other computers can refer to when
they want to match a domain name with its associate
IP number. This IP number is how the particular
server your website resides on is located.
Accessing your domain
manager:
Simply go to your domain registers web site, and
look around for links, which point to something
like, domain manager, manage domain, or something of
that administrative nature. In your welcoming email,
you were sent DNS settings, which look similar to
this example:
NS7.Registrarhost.org 64.38.1.218
NS8.Registrarhost.org 72.232.177.114
Most of the newer registers such as the (OPEN SRS)
based entities have turned this into a 5-minute
process. You simply login to the registrar, select
'manage domain' and you'll be presented with an
option to update your new DNS numbers. Contrary to
popular belief, Network Solutions (netsol) 'now'
also provides an online interface to change these
settings, so this process with them is no longer as
complicated as it used to be, however it's still not
as simple as the OPEN SRS based systems. If your
particular registrar 'does not' provide a domain
manager of some type, then you'll need to send them
a message requesting a change of DNS. This is an
unlikely scenario, as most every registrar now
allows you to manage your own domain settings from a
web based interface.
Once you've accessed the "management interface" of
your domain name, look for a setting, which says
"change or manage DNS settings." In most cases, you
can simply cut and paste the DNS settings we've sent
you directly into the spaces, which correspond to
your DNS management settings. Remember, the DNS
settings we are displaying here are an
"example" as we use different DNS settings
on different servers. Make sure you use the DNS
settings as advised to you in your email.
The 3 to 4 day
propagation period - Understanding what happens
during this time frame:
In short, patience is a virtue. Remember what we
talked about earlier in this chapter regarding the
size and scope of the worlds DNS system? In short,
when you change your DNS settings, these new
settings must propagate throughout the worlds DNS
servers. It also means that every ISP (Internet
Service Provider), must update their DNS records to
reflect these new changes, which in most cases, is
done automatically every 24 hours, but not always
however...
Where do the Root Name Servers receive their
information from?
The Root Name Servers will query "domain registers"
several times a day. Domain Registers, being
entities such as Network Solutions, and the newer
OPEN SRS based systems. The Root Name Servers will
gather this information from the many registers now
in existence, and update their master records
accordingly. Now your ISP must access the Root Name
Servers, and update their DNS records, which reside
on their 'local' DNS server. This process is fully
automated and most ISP's will check the Root Name
Servers for updates every 24-hours. Beware however,
that some lame ISP's will delay this process for as
much as 2 to 4 days in some cases. If that happens,
it will no doubt cause additional confusion, as
everyone else will be reaching your new account on
our servers except you. This is because your ISP has
not updated their DNS records, and or have not
cleared their DNS cache, which means they'll still
be pointing your domain name to your old server. If
it's a new domain name you've registered, then
you'll receive a blank "Site Not Found Page."
DNS Cache and your
ISP:
There is also the issue of DNS cache, which is
something we won't go into great detail about here,
but here's the short version. Every time you access
a site from your ISP, they cache the URL, as well as
its associated IP number. If their network is
properly setup, these DNS cache records should
"Expire" at least every 24-hours. If they did not
(which is often the case), you'll experience this:
You enter your
http://www.mydomain.com/ URL, and it keeps
taking you back to your old server account.
In a large number of cases, it's the result of an
ISP who "Did Not" configure their servers to
"Expire" the DNS cache records at the appropriate
intervals. Unfortunately, this adds additional
confusion to their hosting, and especially the ones
whom are trying to point their domain name to a new
server. Yes, it will make you want to scream
sometimes, however if you understand whom is
actually at fault, then you'll know who to scream at
:)
The DNS propagation
process is not limited to ISP's!
HA.. Just when you thought you had it all figured
out! Unfortunately, there's more folks. The Internet
itself must update/clear its DNS cache as well. When
we say the Internet, we mean the numerous
intermediate "points of access" you're routed
through before reaching your final destination. For
the most part, these intermediate points of access
consist of "Internet Routers" and "Internet Caching
Engines." These too, maintain their own DNS cache,
which assists them in routing traffic/resolving
URL's to the correct destination IP's. Don't worry
though, as Internet routers are usually faster at
clearing their DNS cache than ISP's are.
What to expect during
this 2 to 4 day propagation period:
In most cases, the propagation process will take at
least 48 hours to complete. The first thing that
happens is the "World Root Name Servers" will check
all of the various "Domain Registers for updates.
Ok, so now the Root Name Servers have done their
job. The rest of it is up to the many ISP providers
who "should be" updating their DNS records (at least
every 24 hours), but a number of them will not.
Side effects that can
be expected during the propagation time frame:
It's perfectly normal for strange things to happen
within the 48-hour propagation period, but sometimes
longer. While we could provide a full list of all
the anomalies that can occur during the DNS
propagation period, we'll stick to some of the most
common scenarios that most people experience:
HELP! My friends can reach
my new site, but I'm still being directed to the OLD
ONE!
This is a classic case of your friends ISP (who did
update their DNS records), but yours unfortunately
did not. As a result, your ISP is still pointing
your domain name to the old DNS record, which is
your old hosting account. Wait a couple of more
days, and if it appears that everyone but you can
access your new account, then contact your ISP and
tell them to expire their old DNS cache records.
WOW! http://www.mydomain.com
was taking me to my new RegistrarHost account just a
minute ago, but when I try it now, I'm being taken
back to my old hosting account - what's up with
this?
In all likelihood, your ISP may be in the process of
clearing their DNS cache, and or updating their
local DNS server records. During this small
interval, it's normal to fluctuate between the new
and old web site, as the old DNS records may not
have completely expired from their cache yet. Give
it another several hours and it should be fine.
HEY! My new site comes up for me, but my friends
are being directed to my old one!
Break out the coffee and donuts, and consider
yourself lucky. Your ISP is on the ball and updates
DNS records/ clears DNS cache in short regular
intervals. Your friends may be using an ISP, which
is not as fast, and or efficient at doing so. The
only remedy for this is time. Eventually, the other
ISP's DNS cache will expire and be replaced with the
updated DNS records.
What's going on with my
email? When I try to access it, I receive a "host
does not exist" or a "cannot authenticate" error
message.
This can happen for a number of reasons, but in most
cases, it's because your new DNS records have not
fully completed the propagation process yet.
Consequently, you may be trying to access your old
email account on your "old server", which you may
have already cancelled, or it's in a state of DNS
flux, which means it points to the new server one
moment, and the next, points back to the old server.
Give it some more time and it will eventually settle
down. In the meantime, consider accessing email from
your account using the WebMail based reader. If your
domain has not propagated as of yet, you can access
your email account via WebMail with your temporary
url. Example:
http://216.127.78.7:2082/neomail/neomail.pl
This will allow you to access your default mailbox
on your account. Replace the tempurl with the one we
sent you, and do not remove the :2082 port number in
the URL.
Microsoft FrontPage will
not accept a Username and Password, or displays the
error message (FrontPage Extensions Are Not
Installed).
While you should be able to access FrontPage with
your associated temporary URL (until your domain is
resolving to our servers), this is not always the
case. FrontPage can behave in a number of different
ways depending on which direction the wind is
blowing. In some cases, it will allow you to
initiate an upload session, but upon asking for your
Username and Password, will not recognize them. If
this happens, the best thing to do is wait until
your domain name is answering to our servers. One
thing we know for sure, is FrontPage will work
without much of a problem if you're using the full
www.mydomain.com URL to manage your site with. Feel
free to try it with your temporary url, but we
cannot guarantee it will work.
It's been over a week.
Everybody else can access my new site except me!
Was your domain originally hosted by your ISP? If
so, they may not have deleted this entry in their
DNS files. This results in you, and or anyone else
accessing the net from this "particular ISP" being
directed to your old web site on their servers. A
number of ISP's forget this small detail, which can
result in weeks of utter confusion and frustration.
If this is happening to you, contact your ISP and
make sure they've made the necessary changes to
their DNS records.
Checking your DNS
update status (outside of your ISP):
In the event you're becoming impatient, and or are
wondering if the rest of the world outside of your
ISP can access your new site, you can proxy yourself
to another network and test it there. In many cases,
you'll be surprised to see your site responding
perfectly, yet when you attempt it directly from
your ISP's servers, it does not exist.
There are several services, which allow anonymous
surfing across the net. While this is not the intent
here, they can be used for trouble shooting domain
resolution problems. How? Because they proxy you
through their network, which means your URL requests
are controlled by "their" DNS cache records. These
services update/expire their DNS cache far more
often than ISP's, which makes them well suited for
testing your domain name through a network, which
operates with the latest DNS updates across the web.
To run this check, you can try accessing your site
through one of these services:
http://www.anonymizer.com/
This allows you to
enter a URL, and proxy your request through their
servers. If your site is accessible from these
servers, then chances are, your ISP has yet to
expire their old DNS cache records.
Working on your account during the DNS
propagation period:
You can still work on your new account until your
domain name finds it way to our servers using your
temporary url, which was included in your welcoming
email. Using it at this point will provide a means
for you to access your account, as well as test your
new site by using something like
http://yourtempurl.com/ (obviously you'd
replace it with the url we sent you).
One easy way to check and see if your domain is
answering to our servers yet, is to create a file
called "test.html" and place it in
your web directory (make sure you do not have the
same file name in your old web hosting account).
Keep checking the URL
http://www.yourdomain.com/test.html and see if
it works. When it does, you'll know your domain name
is answering to your account on "our servers", and
has been officially transferred.
Next:
Setting Up Sub
Domains:
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