WAN DNS problems

[JohnNerd]

I'm running an AX88U with Merlin 386.3_2.
I leave LAN DNS off, and use the WAN DNS settings instead.
This works great, but not for an AC87U in bridge mode.
This bridged router will include its own IP-address as DNS no matter what.
First address is from AX88U and the second is always the IP-address of the AC87U.
This leaves the connected machines useless.

To correct this the machines connected to the bridged router/AC87U have manual IP and DNS settings.
How can this be rectified? And why is the bridged router's IP being broadcasted?
All other connected gear through WiFi works as they should and get the WAN DNS.

Please help.

 

[L&LD]

Doesn't sound like it's really bridged?

What firmware are you running on it? Asus/RMerlin or other?

What ports are you using?

Does a full reset on the RT-AC87U fix things?

 

[ColinTaylor]

I leave LAN DNS off, and use the WAN DNS settings instead.

This doesn't sound right. What do you mean by this?

This bridged router will include its own IP-address as DNS no matter what.
First address is from AX88U and the second is always the IP-address of the AC87U.

Again, this sounds wrong. In Media Bridge mode the AC87U shouldn't even be running a DHCP server. Maybe you really mean some other "bridge" mode?

 

[JohnNerd]

Doesn't sound like it's really bridged?

What firmware are you running on it? Asus/RMerlin or other?

What ports are you using?

Does a full reset on the RT-AC87U fix things?

AC87U is in bridge modus running with the latest Asus firmware. I did try a full reset.
AX88U is on 192.168.1.1
AC87U is on 192.168.1.3

WAN DNS is: 1.1.1.1 and 1.0.0.1 still second DNS will be 192.168.1.3 on the connected computer. Where does it get 192.168.1.3 broadcast from? (I even turned off DHCP on the 87U). Strange.

PC connected with LAN cable to AC87U will no matter what show 192.168.1.3 either as first or second DNS.
Sometimes it will work, but after a restart it's back to not working again.

I got it working by fixed IP and putting in manual DNS on each computer, but I'm curious to know why.
Also, it works great on WiFi, no issues.

Thank you very much for your help.