This post is for other unknown people online, who may someday have the same problem.

This is specific to the NM included in Slackware15, it may or may not apply to other distros/releases.

The problem - When using NM, attempts to use non-dnsmasq dns servers such as bind or unbound, fail. The other dns server won't function. Even when the NM configs say to not use dnsmasq for dns. Even if NM is configured to use those other dns servers.

I searched for answers, there have been some people asking the question, but they never got good answers either.

The problem, at least in my case, is that no matter how NM is configured, it is directly loading dnsmasq anyways. In fact, it appears to need dnsmasq for more than just dns services. I tried "chmod -x dnsmasq", NM lost it's ability to configure connections.
Even static ip ethernet connections.

The explanation is that once NM directly starts dnsmasq, dnsmasq starts and uses it's own config file at /etc/dnsmasq.conf - and by default it provides dns services, Including listening on port 53, and allocating that ip socket for itself. Causing other dns servers to fail when they can't use that socket.


The simple solution was to go to /etc/dnsmasq.conf and set "port=0", disabling dnsmasq's dns service but letting it remain active for the other services it provides to NM.

Hope this helps someone somewhere.