nslookup - hide ip address

[Byun Hee Joong]

Server : L1000
O/S : 11.11
Bind : 9.2

Generally, when we test nslookup
We can see server ip-adress like below

C:\>nslookup www.yahoo.com
Server: kns.kornet.net
Address: 168.126.63.1

Non-authoritative answer:
Name: www.yahoo.akadns.net
Addresses: 66.94.230.39, 66.94.230.37, 66.94.230.50, 66.94.230.35
66.94.230.32, 66.94.230.47, 66.94.230.42, 66.94.230.75
Aliases: www.yahoo.com

But, When a client type nslookup
I want to hide server ip-address.

Is it possible?
How can I hide server ip-address?

Please tell me how to setup at server part.

[Cheryl Griffin]

It's not possible. Maybe you need to restrict the client from running nslookup.

How does the client connect to your machine?

[Senthil Kumar .A_1]

Hi,

The query, defeats the very purpuse why you have DNS. DNS is indeed used for resolving the hostname into IP address, and nslookup is one of the troubleshooting utility to see whether you nameservice lookup is fine or not. It does transperantely, what other network program's acheive by using gethostbyname() function. So your question is contradicting the purpose of name resolution.

As pointed previously, you can disable just the usage of the nslookup utility in the client machine.

Regards,
Senthil Kumar .A

[Steven E. Protter]

Shalom,

Due to security concerns nslookup has been deprecated in Linux and perhaps someday in Unix as well.

Its designed with trust in mind. To hide your machine from nslookup, it should be off the network entirely.

If you control the client side, have nslookup blocked or removed as advised earlier.

SEP

[Bill Hassell]

The simplest way is to disable DNS completely. Then add important hostnames into the /etc/hosts file. Just remove the file /etc/resolv.conf and now your DNS server(s) will no longer be available to your local system.

It sounds as if you have security concerns. If so, consider removing shell access to the problem users. Give them a simple menu script as their shell and do not give an option to run nslookup.

[Muthukumar_5]

Hope you can use hosts: entry in /etc/nsswitch.conf file with files only. files will make hostname lookup only with /etc/hosts only.

--
Muthu