# - After upgrade from jessie to strech systemd seems to "ignore" the Postfix startup.
# -
# - Also "systemctl start postfix" does not work.
# -
# - I found out that I simply have to reload systemd with
# -    systemctl daemon-reload
# -
# - But after reboot, again no psotfix daemon is running
# -

# - Finally the following simple command fixed this problem
# -    systemctl enable postfix@-
# -
# - After rebooting, on some systems postfix starts up fine.