Dns
 

Hi

We have two network one is "B" class with public DNS and another "C" class with vpn connection to "B" network and having private DNS. We want to resolve hostname which has entry in public DNS for "C" class machine. In "C" class network the ip get resolved only when we are connected on Internet. If Internet is down the name resolution does not happen. Can anybody guide me how to resolve the hostname when Internet is down.

I received few clues that the name resolution will happen from the private DNS cache database, but did not happend and also not able to figure out.

issue2:

how to clear the cache for hostname which has wrong IP and cached i.e., when i ping with hostname it shows wrong ip and says destination not reachable. Please clarify in this regard also.

thanks.

T. Saravana

Well if your internet connection is down there is no way of verifying that the IP address is correct. Also how are you going to use the DNS or IP address? There would be nothing to use it for (except for your own personal amusement).

You can set yourself up as a DNS server, and import the domains from other locations so you have a local copy, then set yourself up as the primary DNS, and there you are.

To change / remove incorrect DNS / IP pairs you have to know the correct IP addres, so what you can do is compare against trusted sources at regular intervals and over-write any changed files.

If you had a permanent internet connection then if IPs change your DNS servers info should get updated ... but i sincerely doubt that you could convince a system to cache all DNS records locally...

What exactly are you wanting to do?