title: Can't start mongodb server
body: <p>I just installed mongodb server using homebrew as described <a href="https://treehouse.github.io/installation-guides/mac/mongo-mac.html" rel="nofollow noreferrer">here</a></p>
  
  <p>When I run <code>mongod</code> to start the server, I get: 
  <a href="https://i.stack.imgur.com/ZjKRt.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZjKRt.jpg" alt="enter image description here"></a></p>
  
  <p>What am I missing?</p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p><code>mongo -version</code> gives me: 
  <code>
  MongoDB shell version v4.0.0
  git version: 3b07af3d4f471ae89e8186d33bbb1d5259597d51
  allocator: system
  modules: none
  build environment:
      distarch: x86_64
      target_arch: x86_64
  </code></p>