gistfile1.txt

You started mongodb server, but No matter what.  However, when you run sudo status mongodb again, you’ll get
mongodb stop/waiting instead of mongodb start/running

Note:  This condition is largely due to an unclean shutdown, and results in the creation of a lockfile /var/lib/mongodb/mongod.lock.

The fix is a quick two-step process as follows:

Remove the lockfile.
Run the repair script.
This is accomplished as follows:

$ sudo rm /var/lib/mongodb/mongod.lock
$ sudo -u mongodb mongod -f /etc/mongodb.conf --repair
Now when you run sudo start mongodb.  It will report

mongodb start/running, process XXXX