Weird DNS resolution

[Gauthier Siri]

Hello,


I have a domain name, let's say, mydomain.com, properly configured with its public DNS.

I pointing to local device @home.

So i have entries like www.mydomain.com, xxx.mydomain.com etc...

Eerything is working fine.


To avoid going out of my local network to come back in to when i try to access them from my local network (and avoid confidentiality issues, loss of bandwith or whatever you can imagine), i've set up a local DNS server, to redirect those DNS entries to their local IP addresses.


Of course, i set the DHCP on my network to provide this DNS server.


However... it's not working, at least on my computer, with Windows 10.

When i try a nslookup xxx.mydomain.com it doesn't use the local DNS entries, but the public ones ie.

> nslookup xxx.mydomain.com
Server: UnKnown
Address: 192.168.0.250

Non-authoritative answer:
Name: mydomain.com​

Address: 7x.xxx.xxx.xx (my WAN address)
Aliases: xxx.mydomain.com​

When it should return a local address.

When i try on the DNS server directly (actually my NAS, under linux), which is also use itself has DNS, the same command answer properly :

$ nslookup xxx.mydomain.com
Server: 192.168.0.250
Address: 192.168.0.250#53

xxx.mydomain.com canonical name = ns.mydomain.com.
Name: ns.mydomain.com
Address: 192.168.0.250​

To narrow down the problem, i also tried on my wife laptop (on windows 10 too,but maybe older, mine is a new laptop installed 3days ago), and the local resolution works fine.


And even weirder, on my DNS server, if i stop the DNS forwarding, some website continue to be resolved when some other doesn't.

So it's like there is "something" which is still resolving...?


I tried to flush the DNS cache but it doesn't change anything...


Honestly i'm starting to be lost and don't know what can be the issue...


Thanks for your help!

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