URL:
https://github.com/SSSD/sssd/pull/148
Title: #148: SYSTEMD: Update journald drop-in file
lslebodn commented:
"""
Because `man 5 systemd.service` says that.:
```
Behavior of notify is similar to simple; however, it is expected
that the daemon sends a notification message via sd_notify(3)
```
and type simple is really simple because it does not call fork
```
If set to simple (the default if neither Type= nor BusName=, but
ExecStart= are specified), it is expected that the process
configured with ExecStart= is the main process of the service. In
this mode, if the process offers functionality to other processes
on the system, its communication channels should be installed
before the daemon is started up (e.g. sockets set up by systemd,
via socket activation), as systemd will immediately proceed
starting follow-up units.
```
"""
See the full comment at
https://github.com/SSSD/sssd/pull/148#issuecomment-277966548