Thanks Till, which systemd service's dependency got changed?
I compared /lib/systemd/system/systemd-resolved.conf between 18.04 and 19.10, they are same. There is "After=systemd-sysusers.service systemd-networkd.service".
I do NOT know when and who triggers /etc/dhcp/dhclient-enter-hooks.d/resolved script at boot, but it's possible that when this script executed, systemd-resolved.service is not ready for reload or restart.
Thanks Till, which systemd service's dependency got changed?
I compared /lib/systemd/ system/ systemd- resolved. conf between 18.04 and 19.10, they are same. There is "After= systemd- sysusers. service systemd- networkd. service" .
I do NOT know when and who triggers /etc/dhcp/ dhclient- enter-hooks. d/resolved script at boot, but it's possible that when this script executed, systemd- resolved. service is not ready for reload or restart.