I needed two more things mongodb was complaining about in the logs.
YMMV!
Add log dir & file:
$ sudo mkdir /var/log/mongodb/
$ sudo touch /var/log/mongodb/mongod.log
$ sudo chown mongodb:mongodb /var/log/mongodb/mongod.log
Add db dir:
$ sudo mkdir /var/lib/mongodb
$ sudo chown mongodb:mongodb /var/lib/mongodb
Have a nice weekend! 