MongoDB (3.2) doesn't start on Lubuntu 16.04 LTS as a service
The instructions/packages on the MongoDB site are currently available for LTS Ubuntu 12.04 and 14.04 only. The packages are set up to use upstart instead of systemd. You need to create a systemctl file to be ready for systemd. Create it by
sudo nano /etc/systemd/system/mongodb.service
It will look like
[Unit]
Description=High-performance, schema-free document-oriented database
After=network.target
[Service]
User=mongodb
ExecStart=/usr/bin/mongod --quiet --config /etc/mongod.conf
[Install]
WantedBy=multi-user.target
Now you can start the service and check its state by
sudo systemctl start mongodb
sudo systemctl status mongodb
and finally enable it permanently by
sudo systemctl enable mongodb
(Source: How to Install MongoDB on Ubuntu 16.04)
Just run sudo mongod
to start the daemon and then sudo mongo
to access the shell