PREIN

/bin/sh

getent group mongodb >/dev/null || groupadd -r mongodb
getent passwd mongodb >/dev/null || \
useradd -r -g mongodb -d /var/lib/mongodb -s /sbin/nologin \
-c "MongoDB Database Server" mongodb
exit 0

PREUN

/bin/sh

if [ $1 = 0 ] ; then
  /bin/systemctl --no-reload disable mongod.service &> /dev/null
  /bin/systemctl stop mongod.service &> /dev/null
fi

POSTIN

/bin/sh

/bin/systemctl daemon-reload &> /dev/null || :

POSTUN

/bin/sh

/bin/systemctl daemon-reload &> /dev/null
if [ "$1" -ge "1" ] ; then
   /bin/systemctl try-restart mongod.service &> /dev/null
fi