newbie: nslookup question

  • Thread starter Thread starter tim moor
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tim moor

dear dns gurus,
in our datacenter we changed out our primary and secondary dns server.
these servers resolves dns queries for different services we offer. our isp
is forwarding all requests regarding our name-space to these new dns
servers. the clients of our customers points to the dns server of our isp.
how can i find out, if the both newly installed dns server are resolving
the dns requests. from a customer client i tried a

nslookup -querytype=soa mydomain.com and
nslookup -querytype=ns mydomain.com

but this only returns the ip adress from the local windows 2003
domain-controller and a -> dns request timed out. the clients local w2k3 dc
is configured to forward all dns requests to the dns server of our isp. is
there a way to find out, that the new dns server are resolving the requests
?

thanx alot
tim
 
dear dns gurus,
in our datacenter we changed out our primary and secondary dns server.
these servers resolves dns queries for different services we offer. our isp
is forwarding all requests regarding our name-space to these new dns
servers. the clients of our customers points to the dns server of our isp.
how can i find out, if the both newly installed dns server are resolving
the dns requests. from a customer client i tried a

nslookup -querytype=soa mydomain.com and
nslookup -querytype=ns mydomain.com

but this only returns the ip adress from the local windows 2003
domain-controller and a -> dns request timed out. the clients local w2k3 dc
is configured to forward all dns requests to the dns server of our isp. is
there a way to find out, that the new dns server are resolving the requests
?

thanx alot
tim
***************** REPLY SEPARATER ********************
You do this exactly the way an outside DNS server would do it. You first of
all ask one of the root servers (DNS servers are pre-configured with the
root servers).
server a.root-servers.net [198.41.0.4]

When you request mydomain.com, it will return all the servers that serve the
..com domains. Then select one of those:

server A.GTLD-SERVERS.NET [192.5.6.30]

When you request mydomain.com, it will return all the servers that serve the
mydomain.com domain.
mydomain.com
Server: [192.5.6.30]
Address: 192.5.6.30

Name: mydomain.com
Served by:
- ns1.mydomain.com
64.94.117.195
mydomain.com
- ns2.mydomain.com
216.52.121.233
mydomain.com
- ns3.mydomain.com
66.150.161.130
mydomain.com
- ns4.mydomain.com
63.251.83.74
mydomain.com

Select one of those and ask the question again:
mydomain.com
Server: ns1.mydomain.com
Address: 64.94.117.195

Name: mydomain.com
Address: 216.34.94.184


Done!

J.A. Coutts
 
tim moor said:
dear dns gurus,
in our datacenter we changed out our primary and secondary dns server.
these servers resolves dns queries for different services we offer. our
isp is forwarding all requests regarding our name-space to these new dns
servers.

That would normally not be the job of your ISP but rather
the PARENT zone DNS servers (e.g., .com, .edu) to DELEGATE
rather than forward to your DNS servers.

Generally it is best NOT to run your own DNS servers for public
DNS but rather move it back to the REGISTRAR and leave the
ISPs out of this completely.
the clients of our customers points to the dns server of our isp.

They should not need to do this. If I were to become one of your
clients this would make no sense for me (to point anywhere near
your ISP.)

DNS on the Internet is resolve by working from the ROOT SERVERS
("." or DOT zone) downwards through the delegations.
how can i find out, if the both newly installed dns server are resolving
the dns requests. from a customer client i tried a
nslookup -querytype=soa mydomain.com and
nslookup -querytype=ns mydomain.com

You can certainly do it manually with NSLookup but it is easier
usually to just visit the web site http://www.dnsreport.com/
and let them test it all for you.
but this only returns the ip adress from the local windows 2003
domain-controller and a -> dns request timed out. the clients local w2k3
dc is configured to forward all dns requests to the dns server of our isp.
is there a way to find out, that the new dns server are resolving the
requests ?

The key trick you overlooked is specifying WHICH DNS server to
use in your NSLookup command:

nslookup -q=NS DOMAIN_NAME IP.DNS.Server.ToAsk

You start by getting the ROOT DNS servers, then .Com (or whatever
your parent zone), then asking .Com for your DNS server from their
delegations etc.
 
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