Not getting response from NxFilter DNS server

[support200]

NxProxy and CxBlock uses TCP/443 to communicate with NxFilter. When you do regular DNS queries or use Nslookup, you send your queries through UDP/53.

You have 192.168.0.203 as Block Redirection IP and 127.0.0.1 is not associated to any user. So, Login Redirection works and it gets 192.168.0.203 as an answer.

127.0.0.1 works because normally there's no restriction for local traffic by anything mostly a firewall. But you have the same result even if you disable your firewall.

If you don't see any traffic from your nslookup when you use 192.168.0.x IP as the server IP, it means NxFilter doesn't get any traffic through UDP/53. It's blocked somewhere before NxFilter.

People uses something like Wireshark when they want to view network traffic on Windows. https://www.wireshark.org/download.html

[RothKevin]

Good morning and thank you for testing this.

Here's an update from my side:

• Tried changing my ip to static 192.168.0.210. Still having issues with nxfilter as DNS server.
• Enabled debugging via logj4.properties file

Debug showed these kinds of entries or similar:
DEBUG [10-09 07:16:03] - Sending forcesafesearch.google.com./A, id=45714 to udp/208.67.222.123:53

as well as users logged in via cxblock and data.

• After enabling debugging and stopping and starting nxfilter nslookup nslookup gives same response

What I am not understanding is why is 192.168.0.203 coming up as the server address for google.com?


Anyway, within the DNS request logs in Nxfilter I can only see traffic from chrome from the nxfilter pc and the laptop I am testing with. The reason is that both are using cxblock.

I am wondering why DNS filtering works through cxblock/nxproxy, but not when statically assigned.

I understand what you are saying about tracing my UDP 53 traffic but I am not sure how I can do that. Any recommendations?

Update: I am guessing the nslookup queries should be showing up on the logs in nxfilter. But none of that traffic is showing up, so I am guessing that it is not reaching nxfilter server.

[support200]

We just installed a new Windows 11 and installed NxFilter on it using its exe package to see if we have any problem with Windows 11. It worked fine. If I were you I will try to install it on another system to see if it's related to your system settings. Anyway, you need to find where those UDP/53 traffic have gone.

[support200]

You need to find out where your UDP/53 traffic goes. The first step is to find out your NxFilter gets it or not. You can compare the output with when you do nslookup query against 127.0.0.1 on NxFilter system.

[support200]

Yes. I just asked it because your system still has 'DHCP Enabled'. So, your DHCP is disabled now?

Did you see any traffic from 192.168.0.203 on 'Logging > Request'? If it's a network problem, there might be 2 kinds of problem. The traffic goes into NxFilter but it can't respond or it even can't get any traffic from 192.168.0.x through UDP/53.

You may enable debugging as well, https://tutorial.nxfilter.org/i-faq.php#enable-debug

With debugging on, you can run NxFilter from CMD.

cd c:/nxfilter/bin
shutdown.bat
startup.bat

And you can see what happens with your nslookup testing. When you make a query then there should be something on its output in real-time.

[RothKevin]

Current DNS settings on Nx

[RothKevin]

No device with same IP on my network

[RothKevin]

Are you asking me to change to an IP other than 192.168.0.203? Here are my current settings:


When I try using 0.203 as DNS I don't have connectivity.

[support200]

Can you make it a static IP address then? You can change its IP as well to exclude the situation that you have a system having the same IP in your network.

[RothKevin]

Here it is!

[support200]

That's very weird. Can you show me the result of this command then?

ipconfig /all

[RothKevin]

Definitely worth a try. Unfortunately same result 😣

[support200]

For testing purpose, can you disable your firewall on NxFilter system?

[RothKevin]

Thanks for clariying.

So this is interesting. Running nslookup via 127.0.0.1 times out briefly and gives a reply, but running nslookup via 192.168.0.203 gives no reply whatsoever

..


And yes I installed with EXE package

[support200]

Sorry, you mentioned that you installed it using EXE. We add some firewall rules during the install process. Anyway, see if it works when you use 127.0.0.1.