All query's reach our server as expected, but the answer does not get back. (If our DNS server, and the PC sending the query both use a port other port than 53, and we change the NAT entry to map port 53 to an other local port it works OK)
Full configuration in attachment?
Can anyone please help me out?
Is there a secial command to allow DNS-replies to pass to the router ?
There has to be a 1-1 NAT rule in the configuration:
ip nat inside source static 192.168.0.253 188.8.131.52
Only forwarding port 53 UDP and TCP doesn't work.
The DNS server must be configured to supply A records with the local IP address, not the global IP address, otherwise the DNS response does not pass through the router!!! (surprise, surprise) The router translates the ip addresses inside the DNS respones.
It took a long time to find this out, but now everything works OK.
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