RE: [cobalt-users] is dns that important?

[Rodolfo Paiz <rpaiz@xxxxxxxxxxxxxx>]

> To host websites does one have to use DNS or can you
> have clients change their ip address to that of your
> server? What is the advantage of DNS?

DNS ***must*** exist somewhere. This is not subject to debate. *Someone*
must provide DNS services for you. If you're hosting websites and
charging money for it, you should have two separate computers providing
DNS... ideally on two separate networks.

However, that DNS may run on any computer and does not have to be on the
same machine as your sites. In fact, for security (and fault-tolerance)
reasons it is better to have the DNS running on another computer if you
can afford to have two or more servers.

If you're asking these questions, I assume you have no idea how things
work. Let me give you a short narrative of how web browsing works. In
this story, there are four computers named Customer, Registrar, DNS
Server, and Web Server. I will use a real domain as an example, but it's
not mine.

1. Customer inputs www.guate.net into their browser.

2. Customer searches Registrar for guate.net (the domain name) and is
told that guate.net is served by two DNS servers at 200.12.63.2 and
200.12.63.10.

3. Customer asks *either* DNS server (not always the first one) who
www.guate.net is. If that server is down, it asks the other. If neither
server responds, Customer sees error: "www.guate.net doesn't exist".
This is why we must have two, so we hope that *never* will both be down
at the same time.

4. Customer receives a response saying that www.guate.net can be found
at 200.12.63.30.

5. Customer asks Web Server for www.guate.net and the HTTP server
program goes through its httpd.conf file, figures out what site to serve
and returns the start page.

6. Customer browser displays the www.guate.net page.

--------

If there were no DNS, it would be *impossible* to get the webpage
properly starting with a name. You'd have to ask the browser for an IP
address.

But if you do that, then you must host only one site per IP address.
Name-based hosting doesn't work because... you're not using names at
all.

(So Wayne... something is going on, but trust me you have DNS services.)

--
Rodolfo J. Paiz
rpaiz@xxxxxxxxxxxxxx <mailto:rpaiz@xxxxxxxxxxxxxx>