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Old 10-19-2016, 07:38 AM   #1
shinobi59
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DNS lookup on my host resolves to an external network


Problem: dns lookup on my host (behind a firewall) resolves to a host that is external to my network.

CentOS 6.2

My net 192.168.20.0/24 | Gateway 192.168.20.1

Router: 192.168.20.1
Router: 10.10.30.254
Router: 192.168.40.1

My concern is that my system is being cloned (somehow) and that traffic back to my system is being routed through the external (seems unlikely).

Any ideas?

Also. When I ping the 2nd router 10.10.30.254 it responds to a windows PC but not to my CentOS system.

Any help very much appreciated.

Last edited by shinobi59; 10-19-2016 at 07:42 AM. Reason: Additional information
 
Old 10-19-2016, 07:41 AM   #2
shinobi59
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Also:

When I ping the 2nd router 10.10.30.254 it does not respond, however, pinging from a windows pc it does respond.
 
Old 10-19-2016, 10:38 AM   #3
lazydog
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Post the output of resolv.conf and run route -n and post that output too.
Please paste your output in between the code tags [ code ] [ /code ] without spaces to keep everything readable.
 
Old 10-26-2016, 03:04 PM   #4
pingu_penguin
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Quote:
Problem: dns lookup on my host (behind a firewall) resolves to a host that is external to my network.
Obviously , you are using a Class C network ip range. DNS will resolve internet addresses, not private ips.

Quote:
When I ping the 2nd router 10.10.30.254 it does not respond, however, pinging from a windows pc it does respond.
check if ping/icmp is blocked on your host (Centos).
 
Old 10-26-2016, 03:35 PM   #5
jefro
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Might try dig or nslookup for results between windows and linux.

I don't think the OP really does want to use dns for local host names but if so that would be a different deal. I assume the OP is wanting FQDN resolution.
 
  


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