When running under systemd control, sfptpd should not be
explicitly run as a daemon. So, the following option should not be
enabled in the sfptpd config file:
# Configure sfptpd to run as a daemon
# daemon
If this option is enabled, systemd will identify sfptpd as a
daemon not under its control and it will be terminated.
This becomes apparent if the sfptpd service terminates/exits very quickly after
startup without any apparent cause.