Which DNS server is used when there are multiple network interfaces?

5

I have two network interfaces on my computer on my Windows PC.

Primary and Secondary DNS servers are defined per network interface so I can define 2 sets of DNS servers on two network interfaces.

When looking up for a server name, which DNS server is used and why?

e-mre

Posted 2011-05-12T06:55:47.887

Reputation: 1 125

Answers

0

As far as I know windows implements interface priority which you could alter. I think it uses the connection with the highest priority, and from there it`s DNS server.

xciter

Posted 2011-05-12T06:55:47.887

Reputation: 524

Where can I see priorities and how can I alter them ? – e-mre – 2011-05-26T07:24:17.377

Go to network connections, hit the alt key and go to advanced/advanced settings. – xciter – 2011-05-26T12:30:08.903

0

I haven't checked this, but my assumption would be that the DNS servers defined on the interface that has the default gateway will be tried first followed by the servers on the other interface.

Easiest way to check for sure is to capture your network traffic using Microsoft Network Monitor or a similar tool.

Andrew Cooper

Posted 2011-05-12T06:55:47.887

Reputation: 1 249

AFAICT Windows will try only the first DNS server. If it says "address unknown", Windows will not query other networks. – MSalters – 2018-07-31T14:26:27.863

Default gateway is also defined per network interface, so two network interfaces can have two different default gateways defined, so it must be something other than that I guess. – e-mre – 2011-05-12T07:18:07.357

1Capturing the network traffic would answer "which" but would not answer "why" – e-mre – 2011-05-12T07:18:50.617