MongoDB not working. "ERROR: dbpath (/data/db) does not exist."

I'm getting the following error when I try to run "mongod" in the terminal. I've tried uninstalling, reinstalling, and restarting the machine. Any suggestions on how to get it working would be amazing.

ERROR:

dbpath (/data/db) does not exist.
 Create this directory or give existing directory in --dbpath.
 See http://dochub.mongodb.org/core/startingandstoppingmongo

Side note: Node also stopped working on my machine around the same time that I got this error.

events.js:72
        throw er; // Unhandled 'error' event
              ^
Error: failed to connect to [localhost:27017]

Any help would be much appreciated!

This should work to ensure that the directory is set up in the right place so that Mongo can find it:

sudo mkdir -p /data/db/

sudo chown `id -u` /data/db

You need to create the directory on root /data/db or set any other path with the following command :

mongod --dbpath /srv/mongodb/

See the example link

I solved the problem with :

sudo mongod --dbpath=/var/lib/mongodb and then mongo to access the mongodb Shell.