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DNS Problems from WLAN to LAN

ChocolateRain
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Last Modified: 2012-05-12
Hello all.

I have a problem with DNS over the WLAN.  I can ping internal resources by host name but I can't browse to the network and see anything (our WLAN and LAN networks are on separate VLANs).  I can't get to any of our internal websites.

I imagined that this had something to do with some ports being blocked between the VLANs but that isn't the case, the firewall rules allow all protocols in both directions.
 
The DHCP is being doled out by the WAPs instead of any AD integrated DHCP, yet the computers connecting over the WLAN are still pointing to the correct DNS servers.
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Are you using a proxy for internet traffic?

Commented:
if you can ping via hostname, dns is not your problem. from  a wirless connection run a tracert to your server and post the results.

Author

Commented:
No Proxies on our network.

Author

Commented:
Both Tracert's have 1 hops.

tracert for hostname shows up with "Destination host Unreachable"

tracert for FQDN shows up successful

Commented:
Can you run this command ROUTE PRINT and send us the output.  I would like to see what interface you have under 0.0.0.0 mask 0.0.0.0 and the metric values

Author

Commented:
Here is the route print.  NETBIOS over TCP/IP was already enabled and adding the domain as the suffix didn't work either.

Route-Print.png
Leon FesterSenior Solutions Architect

Commented:
Can you access the sites by IP address?

Author

Commented:
Yes, IP address access seems to be working fine.
Leon FesterSenior Solutions Architect

Commented:
Do you have a WINS server running on your network?
I have experienced some issues with VLAN's at a client where they were running WINS and some sites weren't accessable.

The fix was using FQDN since they were trying to phase out WINS anyways.
If you're running WINS then check that the records in WINS have the correct IP's.
SteveArchitect/Designer
CERTIFIED EXPERT

Commented:
just to confirm some details:

You have a network 'called LAN' on one Vlan, and another network @called WLAN on another VLAN.
IP traffic is fine but DNS traffic isnt.

Questions:
Why are they on seperate VLans?
Do clients on both VLANS use the same DNS server?
Is there a domain on LAN, and if so, are the clients on WLAN also members?
Have you tried plugging a WLAN client into the LAN by cable to check it works OK on the same LAN?

Author

Commented:
They are on separate VLANs so broadcast traffic between the WLAN and the LAN don't mingle.  We've actually got that specific client working by changing their TCP/IP settings to append the domain to their host name.

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