difference between WAN and LAN DNS settings options

[jata]

One thing I don't fully understand is how/what DNSFilter does.

I have found that I must set the adgaurd device to 'no filtering' to prevent all client traffic being reported as from the router in adguard logs/stats. I just don't really understand what is happening to achieve this.

Can anyone explain? I did look at the merlin wiki but there is not enough info for me to get it.

 

[ColinTaylor]

One thing I don't fully understand is how/what DNSFilter does.

It intercepts DNS requests just before they are routed and changes the destination address of the packet.

 

[jata]

It intercepts DNS requests just before they are routed and changes the destination address of the packet.

Thanks.

So if global is set to router then unless configured otherwise in dnsfilter clients are routed as if dnsfilter is not enabled.

so what does the ‘no filter’ setting do as I don’t get what it does but I like it . I set my adguard server to no filter and then clients are correctly identified in adguard.

 

[ColinTaylor]

Thanks.

So if global is set to router then unless configured otherwise in dnsfilter clients are routed as if dnsfilter is not enabled.

so what does the ‘no filter’ setting do as I don’t get what it does but I like it . I set my adguard server to no filter and then clients are correctly identified in adguard.

See the explanation in the GUI:

"No Filtering" will disable/bypass the filter, and "Router" will force clients to use the DNS provided by the router's DHCP server (or, the router itself if it's not defined).

"Router" is for clients that either don't use (or ignore) the DNS servers provided by DHCP, or have hard-coded DNS IP addresses (e.g. IoT devices). "No filtering" means the specified client is not affected by DNSFilter.

 

[jata]

I had read this in the GUI but misinterpreted it. I thought router was - use DHCP (or WAN if no DHCP) - i.e. normal behaviour - and no filtering was direct to WAN.

So the main takeaway is enabling DNSFilter and setting global to 'no filtering' is the same as having DNSFilter disabled but setting global to router forces everything to use DHCP settings. Got it the wrong way around.

This makes sense now so thanks @ColinTaylor

This also explains why I see some DNS traffic that is obviously from my hue bridge coming via the router (these have been impacted by the 'router' setting) and some correctly tagged as from hue bridge . It is strange that some hue bridge DNS traffic comes through like this but not all?

 

[loveleeyoungae]

This also explains why I see some DNS traffic that is obviously from my hue bridge coming via the router (these have been impacted by the 'router' setting) and some correctly tagged as from hue bridge . It is strange that some hue bridge DNS traffic comes through like this but not all?

This seems not to be related to DNS Filtering, but maybe because the Router Advertisement is enabled? (On AsuswrtMerlin the setting is "Advertise router's IP in addition to user-specified DNS" on LAN>DCHP Server page. Can't be turned off on stock firmware).

When RA is enabled, some devices may still use the router as their DNS server, hence Adguard Home will only see their traffic as if all are coming from the router.

 

[ColinTaylor]

This seems not to be related to DNS Filtering, but maybe because the Router Advertisement is enabled? (On AsuswrtMerlin the setting is "Advertise router's IP in addition to user-specified DNS" on LAN>DCHP Server page. Can't be turned off on stock firmware).

When RA is enabled, some devices may still use the router as their DNS server, hence Adguard Home will only see their traffic as if all are coming from the router.

I think you are mixing up your terminology. "Router Advertisement" is an IPv6 function, whereas "Advertise router's IP..." is one of the options returned by IPv4 DHCP.