Petr Menšík writes:
Am I missing something?
Yes, system is being shoved down your gullet, whether you like it or not.
would NetworkManager.conf:
dns=default
Write resolv.conf again? Can I make it rewrite after disabling
systemd-resolved? Why doesn't it restore /etc/resolv.conf on
systemd-resolved shutdown?
Yes, /etc/resolv.conf is a symlink. Apparently NetworkManager has been
changed to write /run/NetworkManager/resolv.conf instead, so you can set
/etc/resolv.conf symlink to point to it.
This whole house of cards is an epic fail. There is already a perfectly
usable architecture in place to handle this: alternatives. Both
NetworkManager and systemd should use alternatives to claim dibs on
/etc/resolv.conf, and alternatives will manage the symlink itself.
This is just plain dumb. /etc/resolv.conf should be an alternatives-managed
link. If it were, you'd immediately know how to obtain the list of all the
alternative configurations, and have a simple mechanism for selecting how
you want DNS to be configured, and complete freedom to use or not use
systemd-resolved. I refuse to believe that this obvious solution never
occured to anyone, instead it was decided to intentionally cram systemd-
resolved down everyone's throat and make people jump through hoops to get
rid of it.