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DNS query for ssh hostname

0

Hi all, I installed a Redhat system and configured hostname for the machine say redhatlinux6.4. From Window2K8 server i tried to putty this machine with hostname but not IP address(I ensured /etc/hosts on windows system is not having hostname to IP mapping of Linux machine) as expected the putty connection failed but i didn't find any dns queries in wireshark which i am hoping to get generated by the client to find out the ipaddress of the hostname.I would like to know why is this so?

asked 04 Jun '13, 18:09

krishnayeddula's gravatar image

krishnayeddula
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accept rate: 6%

One Answer:

2

Possible causes are:

  • No DNS server configured on the server, so it doesn't know who to ask
  • The DNS server is configured but in a different subnet and no default gateway in place or configured to reach it
  • The server knows the address already (DNS cache) and doesn't have to ask. Clear the DNS cache using "ipconfig /flushdns" on a command prompt
  • you're capturing at a point where the DNS packets are not coming throught. I guess you're capturing locally on the Win2k8 server. Maybe it has multiple NICs and uses one that you do not capture on

...and probably a few more.

answered 04 Jun '13, 18:30

Jasper's gravatar image

Jasper ♦♦
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accept rate: 18%

Thanks Jasper.In my case the culprit was your point no.2/

(05 Jun '13, 15:58) krishnayeddula