The latest postgrey come with a broken postgrey.service, that fails with systemd.
Look like its trying to replace environment from /etc/conf.d/postgrey and i'm not familiar if/how it works, but at least the
--$POSTGREY_ADDR is being build inside the /etc/rc.d/postgrey script and doesn't exists in /etc/conf.d/postgrey, so at least that part is broken. Also, by experimentation, i found that --$VAR doesn't work, but $VAR where $VAR="--option" is valid.

I suggest that the POSTGREY_ADDR is added directly to the /etc/conf.d/postgrey for both types of connectors (unix and inet), we lose the dynamic config but at least is valid :)

example:
# inet
#POSTGREY_ADDR="--inet=127.0.0.1:10030"
# unix
#POSTGREY_ADDR="--unix=/var/spool/postfix/private/postgrey"

Also, the postgrey.service refers a $POSTGREY_BIN, that isnt defined anywhere (only in /etc/rc.d/postgrey), so it should be replaced with /usr/sbin/postgrey directly, as it will not change anyway. Several other variables ($GROUP, $USER, $PIDFILE) dont exists also and should be replaced with static values or added to the /etc/conf.d/postgrey

Better yet, read this:
https://github.com/mgorny/gentoo-systemd-units/wiki/Why-not-EnvironmentFile%3F

and totally remove the /etc/conf.d/postgrey and patch/pressure upstream to support a config file.


Version: postgrey-1.34-6

syslog error:
==> errors.log <==
Oct 9 10:59:56 paquete systemd[1]: [/usr/lib/systemd/system/postgrey.service:10] Invalid executable path in command line, ignoring: $POSTGREY_BIN --daemonize --$POSTGREY_ADDR --group=$GROUP --user=$USER $POSTGREY_OPTS --pidfile=$PIDFILE --greylist-text="$POSTGREY_TEXT"

systemd error:
# systemctl status postgrey.service
postgrey.service - Postfix Greylisting Service
Loaded: error (Reason: Invalid argument)
Active: inactive (dead)
CGroup: name=systemd:/system/postgrey.service

Steps to reproduce:
1- install postgrey on a systemd enabled system
2- watch the logs complain about wrong command for postgrey.service