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IPSec Site-to-Site VPN DNS resolving issues

Experts,

I'm having a bit of a strange problem.  I've recently stood up a stie-to-site vpn between two sites with static IPs.  Both sites are using a Cisco RVS4000, and the VPN came up with no issues.

Now that the VPN is up, I'm having DNS issues.  On the remote end, I have clients set to use the DNS server in the primary site.

I can hit the server via its internal IP, but whenever I try and resolve any host names, DNS is returning the external IP address of the primary site.

I've flushed the DNS cache on all sides, and made sure that the internal IP is the only thing supplying clients with DNS addresses - but unfortunately - I'm still looking at my external IP whenever I try to resolve internal host names through the VPN.

I haven't seen something like this before, so anybody that has any insight - it would be more than welcome.
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usslindstrom
Asked:
usslindstrom
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1 Solution
 
PapertripCommented:
What software are you running for your DNS server?  Does this all resolve correctly on the primary side?  Do you have separate internal and external zones?

Need more info.
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usslindstromAuthor Commented:
Primary site is AD.  DNS server is also a DC.

Primary site works fine.

No separate internal or external zones, only internal.  External DNS is being handled by www name provider.

Both sites were previously using a GRE tunnel (Cisco 2600s) but were recently upgraded to the small business router (RVS4000) that only supports IPSec tunnels.  In the router upgrade, it was planned to redo the servers on the remote site as well, but we've made it to the point where we're at now with this DNS problem.
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usslindstromAuthor Commented:
Disregard.  A network adapter on the unit (even though disabled), had entries in it's DNS fields.

For some reason, these were causing the problems, and after they were removed - everything worked as intended.
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usslindstromAuthor Commented:
Solution required editing disabled NIC and removing DNS entries.
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