What the purpose of having more than two nameservers? I'm not really savvy on the whole DNS/nameserver thing...all i know is that you need two because you do...lol

why do some hosts have 20 or more?

it is simple
Purpose is to give correct information in case that first server do not work and so on

if NS #1 do not work, browser will ask NS #2,
if NS #2 do not work, browser will ask NS #3
...
anyway
many people host a both NS on same server just because they have to. (and usually they host their site on same server so it is not important because if that server is down, all service is down)

it is simple
Purpose is to give correct information in case that first server do not work and so on

if NS #1 do not work, browser will ask NS #2,
if NS #2 do not work, browser will ask NS #3
...
anyway
many people host a both NS on same server just because they have to. (and usually they host their site on same server so it is not important because if that server is down, all service is down)

that's what i was thinking at first....but do registrars let a domain name have more than 4 nameservers?

would you actually tell your hosting clients..."we have 16 nameservers...assign all of them to your site :)"

i guess it's for redundancy then, if one happens to go down, just send an email out with another nameserver they could use?

Just to clarify, it's not actually your browser going to NS#3... its the ISP (and I believe their DNS server), and it picks one randomly. There is really no advantage to have more than 2 nameservers if the DNS servers for both are on the same server (thus the same DNS server) as if it fails, both will fail.

Depending on the registrar, you may or may not be able to add more than a few nameservers. Some hosts also have multiple nameservers simply because they have several different servers, so depending on which server you are set up on, the corresponding nameservers are provided.

Why do some companies have 20 or more?

One reasn is because they setup each of their servers with a different set of nameservers. i.e.:

Server #1
ns1.nameserver.com
ns2.nameserver.com

Server #2
ns3.nameserver.com
ns4.nameserver.com

Server #3
ns5.nameserver.com
ns6.nameserver.com

etc.....

so you can't just have one dns server in a cluster?

so you can't just have one dns server in a cluster?
Sure you can.... I believe so anyways. I was merely pointing out ONE WAY companies end up having multiple DNS servers. I believe there are many different ways to setup your DNS servers....

But when I used to own a hosting company, that's the way I used to do it.... a different set of nameservers for each new server I added.

that would make sense then...didn't think about that one, i suppose that'd be the way i would do it too...(maybe one of these days i'll need more servers :D)

it is simple
Purpose is to give correct information in case that first server do not work and so on

if NS #1 do not work, browser will ask NS #2,
if NS #2 do not work, browser will ask NS #3
...


That's true. But queries do NOT go in order. They are random. just because you have servers listed 1 2 3 4 does not mean that's the order they will use.

so you can't just have one dns server in a cluster?
No. You cannot.

thanks guys...i feel a bit more edumacated now....lol

Well hmmm...

The whole point of DNS is to tell things where to go, basically.

In saying that, you can tell it to do whatever. If you have clients in 20 different countries, you can setup 20 different DNSes to point to 20 different servers etc. Maybe it's a gaming network or something.

Some are for redundancy, some are for performance, some are for efficiency etc.

List goes on. The more the better depends; just depends how they're used.

There's like a gazillion ways you can implement them. You can create your own system, i.e Something Google would do.

I'd suggest you go to:
www.wikipedia.org / www.howstuffworks and look up DNS.

You'll get a better understanding.

In the end, all domains go through 7 super computers which is basically the backbone of the internet. Verisign operate 2 of them I believe. Anyway, from there they go to your network or DNS or whatever you decide to tell them where to go.

Sorry, I don't want to get technical and just explained it as easily as I could.

"You don't understand it unless you can explain it to your Grandmother." - Einstein.

No. You cannot.


Yes, you can.

--Tina

better redundancy, better response if the nameserver queries is geographically closer to the dns resolver being used.

Yes, you can.

--Tina

Sorry Tina, im pretty sure that you have to have atleast 2 name servers, thats not to say they carnt be the same physical server.

Good reduadancy can come from services like dnsmadeeasy.com

Sorry Tina, im pretty sure that you have to have atleast 2 name servers, thats not to say they carnt be the same physical server.

Good reduadancy can come from services like dnsmadeeasy.com


That's not the question I was reading. I took it as asking if you could have one server handling DNS for many different web servers. Yes, that can be done.

--Tina