Trying to understand DNS

[i***@gmail.com]

Hi,
So... can anyone tell me - does the nameserver for the domain "google.com" have the IP address for google.com, AS WELL AS the ip addresses of the nameservers for "hello.google.com"?
Just saw a youtube video on the subject, trying to understand the whole thing..... :)


Thanks.

[Barry Margolin]

Post by i***@gmail.com
Hi,
So... can anyone tell me - does the nameserver for the domain "google.com"
have the IP address for google.com, AS WELL AS the ip addresses of the
nameservers for "hello.google.com"?
Just saw a youtube video on the subject, trying to understand the whole thing..... :)

There is no "hello.google.com" subdomain.

If there were, it could be stored in the same zone as google.com, so
that these records would be returned by the google.com nameservers. Or
the subdomain could be delegated to different servers, in which case the
google.com nameservers would just have the NS records for the subdomain.

[Pascal Hambourg]

Post by Barry Margolin

Post by i***@gmail.com
So... can anyone tell me - does the nameserver for the domain "google.com"
have the IP address for google.com, AS WELL AS the ip addresses of the
nameservers for "hello.google.com"?

There is no "hello.google.com" subdomain.
If there were, it could be stored in the same zone as google.com, so
that these records would be returned by the google.com nameservers. Or
the subdomain could be delegated to different servers, in which case the
google.com nameservers would just have the NS records for the subdomain.

Not only the NS records but also the associated address records if their
names belong to the parent or child zone.

[i***@gmail.com]

Post by Pascal Hambourg
Not only the NS records but also the associated address records if their
names belong to the parent or child zone.

Sorry I don't understand what this means YET, Pascal! :) Give me a bit of time.

[Ramon F Herrera]

Post by i***@gmail.com

Post by Pascal Hambourg
Not only the NS records but also the associated address records if their
names belong to the parent or child zone.

Sorry I don't understand what this means YET, Pascal! :) Give me a bit of time.

What they are trying to tell you is that the server in charge of the
.com top level domain can tell your client who is the server for
google.com and that one can either tell you:

(a) I have the IP address of hello.google.com

or

(b) I do not have such address, but I know of a server that does.

De nada...

-Ramon

ps: There is an excellent tool, "dig" which will allow you to experiment
and learn. It comes with Linux.

[i***@gmail.com]

OK, we'll get into more complicated things later, I'm just trying to understand from the beginning :) Sorry, what's an NS record?

[Barry Margolin]

Post by i***@gmail.com
OK, we'll get into more complicated things later, I'm just trying to
understand from the beginning :) Sorry, what's an NS record?

NS records specify the nameservers for delegated subdomains.

So if the nameservers for hello.google.com were ns1.netsol.com and
ns2.netsol.com, the google.com zone would contain records like:

hello IN NS ns1.netsol.com.
IN NS ns2.netsol.com.

Maybe you should read the DNS section of TCP/IP Guide:

http://www.tcpipguide.com/free/t_TCPIPDomainNameSystemDNS.htm

[Pascal Hambourg]

Post by Barry Margolin

Post by i***@gmail.com
OK, we'll get into more complicated things later, I'm just trying to
understand from the beginning :) Sorry, what's an NS record?

NS records specify the nameservers for delegated subdomains.
So if the nameservers for hello.google.com were ns1.netsol.com and
hello IN NS ns1.netsol.com.
IN NS ns2.netsol.com.

And if the nameservers names for hello.google.com were ns1.google.com
and ns2.hello.google.com instead, which belong to the parent and child
zone respectively, the google.com zone would contain additional "glue"
records like :

ns1.google.com. IN A 192.0.2.1
ns2.hello.google.com. IN A 192.0.2.2