DNS proxy not working

[Farzana]

Hello,

We are currently getting resolve-fail events for DNS. 

Failed to resolve domain name: after trying all attempts to name server(s): 8.8.8.8 8.8.4.4

DNS server is in loopback.2 Interface/Untrust/IP:203.44.x.x

Below are some pics of DNS proxy settings, session details. Can someone please shed some light what are we missing?

[reaper]

I'm assuming your loopback interface is actually in the trust zone?

Have you tried setting the DNS proxy to use the upstream DNS servers your ISP provides, as they may provide better service than the google ones.

203.40.0.0/13 appears to be located in Australia, so you may benefit from using DNS closer to your office to prevent running into peering issues

[Farzana]

@reaper thank you for your response!

Actually loopback is in the untrust zone. I have checked the admin guide and it does not specify that Interface needs to be in the trust zone. 

Can you please clarify?

[reaper]

The log you attached shows the source to be an internal IP in the trust zone going out to untrust 8.8.4.4

So if your dns proxy is on a loopback in the untrust zone, the log you attached does not match your dns proxy

Did you configure your clients to use the IP of your DNS proxy interface as their DNS server ? For the proxy to work, the clients need to use "the firewall" as their preferred dns server (or the internal DNS needs to use the firewall as it's upstream server)