I quite agree with @GeekSmith here. We disabled systemd-resolved on bionic and install ifupdown instead since we install this on server that have a static configuration and we don't want systemd-resolved to modify anything in the resolv.conf file.
Only during the initial installation time of the server we use dhclient to get an IP address. The result is that the resolv.conf file is not modified by dhclient despite systemd-resolved being disabled. To work around this issue, we simply deleted the /etc/dhcp/dhclient-enter- hooks.d/resolved file as we don't need it anyway. A cleaner way of course it to actually test in the file if systemd- resolved is used, as @GeekSmith's patch does. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1745463 Title: Disabling systemd-resolved breaks dhclient resolvconf integration Status in resolvconf package in Ubuntu: Expired Status in systemd package in Ubuntu: Invalid Bug description: To reproduce, mask resolved: sudo systemctl mask systemd-resolved.service ...then disable network-manager for ifupdown interfaces: $cat /etc/NetworkManager/NetworkManager.conf [main] plugins=ifupdown,keyfile dns=default rc-manager=resolvconf [ifupdown] managed=false [device] wifi.scan-rand-mac-address=no ...and reboot. You'll note that resolvconf integration with dhclient is now broken. Interfaces listed in /etc/network/interfaces or /etc/network/interfaces.d/* will not provide DNS configuration in /etc/resolv.conf and /run/resolvconf/interfaces/. This is because /etc/dhcp/dhclient-enter-hooks.d/resolvconf defines "make_resolv_conf()" as a valid function for the BOUND case, but /etc/dhcp/dhclient-enter-hooks.d/resolved undefines it (who's nasty now, eh?) even though resolved is masked. The file existence check in the beginning of /etc/dhcp/dhclient-enter- hooks.d/resolved should be more thorough, i.e. it should ensure that resolved is enabled, rather than simply look for the existence of /lib/systemd/systemd-resolved. This works for me: -if [ -x /lib/systemd/systemd-resolved ] ; then +if [ -x /lib/systemd/systemd-resolved ] && systemctl -q is-enabled systemd-resolved ; then Arguably, /etc/dhcp/dhclient-enter-hooks.d/resolvconf should implement a similar check, looking for /run/resolvconf/enable-updates as a condition for meddling with DNS settings. If desired, I'll file a separate bug for that package. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/resolvconf/+bug/1745463/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp