CentOS 7.5 image running on linode.
unbound running on localhost.
Have to use a cron job once a minute to keep /etc/resolv.conf using the localhost for name resolution - whenever NetworkManager gets restarted (usually only a system boot) it gets over-written.
It seems every distro has a different way of preventing NetworkManager from replacing that file.
I found instructions for Fedora that said create /etc/NetworkManager/conf.d/no-dns.conf containing
[main] dns=none
That doesn't seem to have any effect.
Poking around, I find a file on boot seems to be created called
/var/run/NetworkManager/resolv.conf
It has most of the contents of what ends up in /etc/resolv.conf - except w/o the last line, which just reads rotate in generated /etc/resolv.conf.
It says it's generated by NetworkManager (both /etc/resolv.conf and the one in /var/run/NetworkManager) but neither are specific enough to indicate what is causing them to be created so I can turn it off.
Anyone know how to tell NetworkManager to just not create that file?
Using a cron job to overwrite it once a minute works but there must be a proper way.
I really wish KISS was a design goal when designing system configuration.