DNS Search order accross two networks

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DNS Search order accross two networks

I'm stuck on one issue with setting up the DNS for my network. I have two networks, one is ethernet (for the internal company network, servers and LDAP), the other is the WiFi for internet access. What I can't figure out is how can I have a DNS search on the Ethernet's network first and if it does not find the route, go out to the WiFi second?

The DNS works correctly on my OSX Server machine and when I have a client machine that is on the internal ethernet network only. The problem comes when I try to add the client machine on to the WiFi too.

In the Network panel on the client machine, if I make the WiFi first, internet servers resolve fine but the internal network breaks. I switch them around and put the ethernet first, the internal network works but the WiFi DNS breaks.

Any thought on how to make the two co-exist and search one domain then the other?

Thanks,

-R

Posted on Jul 25, 2013 4:20 PM

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Answer 1

Linc Davis

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209,547 points

Jul 25, 2013 4:52 PM in response to renderbox

The company network must have an internal DNS server that resolves both internal and external domain names. Use that as your primary DNS.

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Answer 2

renderbox Author

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Jul 25, 2013 5:13 PM in response to Linc Davis

What if the internal DNS does not have access to the Internet?

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Answer 3

Linc Davis

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209,547 points

Jul 25, 2013 6:08 PM in response to renderbox

It must. Otherwise nobody would be able to resolve external domains.

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Answer 4

renderbox Author

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Jul 25, 2013 6:44 PM in response to Linc Davis

So the problem is that you can't have a different DNS for each network?

The point of the Ethernet network is to not have it exposed to the internet. It's for security reasons that it can not be on the internet.

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Answer 5

Linc Davis

Level 10

209,547 points

Jul 25, 2013 7:21 PM in response to renderbox

So the problem is that you can't have a different DNS for each network?

Look at it this way. Suppose your web browser makes a request for a page at foo.com. The name goes to the DNS client to be resolved. Without resolving it, the client would have no way of knowing whether foo.com is on the Ether network or the Wi-Fi network. It needs to get the IP address from a DNS server before it can make that determination. So it's impossible for it to query different servers depending on the domain. It queries one server for all domains.

What DNS server do your coworkers use?

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