ASUS router DNS check fix
After updating the firmware of my Asus RT-AX92U to version
184.108.40.206.388_22525-gd35b8fe, I've noticed two DNS requests to
dns.msftncsi.com every minute. My RT-AX92U is used as an access point, so there is zero reason to check for WAN availability. Additionally
DNS is unchecked in
Administration > System > Network Monitoring.
Ok, let's verify the settings in nvram:
dns_probe=0 dns_probe_content=* dns_probe_host=
Yep, it's not active and there is no host set either. So why is it doing a DNS check? Apparently
dns.msftncsi.com was hard-coded as default and the
dns_probe setting is ignored.
ssh into the RT-AX92U and run the following commands:
nvram set dns_probe_host=127.0.0.1 nvram commit
P.S.: It might also be possible to do this via the UI, but I haven't tried that. Check
Administration > System > Network Monitoring, enter
127.0.0.1 in the field
Resolve Hostname, and click
Apply. After that one can uncheck
DNS and click
Apply again, although the disabled state is ignored anyway.