How does Windows deal with DNS?

Question

Domain Name System

I have a DNS server.
In the connection settings, the router is specified as the first server, and this server is assigned the second.
I make a request - no answer.
I swap the first and second server and everything works.
What is the reason for this behaviour?
Shouldn't the system, having found the address on the first server, turn to the alternative one?
Is it possible to change this behavior without swapping them?

Answer 1

What is the reason for this behaviour?

It's not accurate here, but it seems like the dns client selects one of the specified servers "randomly". Tipo Round-robin - but only on the client. If the host is not available, it moves on to the next one.

Shouldn't the system, having found the address on the first server, turn to the alternative one?

No, if the server answered that there is no such host, then there is no point in looking further. All this comes from the rules of network design. And the problems come from those who did not bother to get acquainted with them.

Is it possible to change this behavior without swapping them?

Write your own dns client, put in it the logic you need. Or get it right in the first place.