title: How do I start a notebook server?
body: <p>I am trying to follow along <a href="https://research.google.com/colaboratory/local-runtimes.html" rel="nofollow noreferrer">this tutorial</a> in order to use a local runtime in Collab</p>
  <p>In Step 3, it says:</p>
  <pre><code>Step 3: Start server and authenticate Start server and authenticate
  New notebook servers are started normally, though you will need to set a flag to explicitly trust WebSocket connections from the Colaboratory frontend.
  
  jupyter notebook \
    --NotebookApp.allow_origin='https://colab.research.google.com' \
    --port=8888 \
    --NotebookApp.port_retries=0
  </code></pre>
  <p>I use the commandline and paste the above code.
  My browser (Chrome) opens the following page:</p>
  <pre><code>http://localhost:8888/tree
  </code></pre>
  <p>It looks like this:</p>
  <p><a href="https://i.stack.imgur.com/HRKIy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HRKIy.png" alt="enter image description here" /></a></p>
  <p>The tutorial goes on saying:</p>
  <pre><code>Once the server has started, it will print a message with the initial backend URL used for authentication. Make a copy of this URL as you'll need to provide this in the next step.
  </code></pre>
  <p>I do see this, it looks like this:</p>
  <p><a href="https://i.stack.imgur.com/iPPZy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/iPPZy.png" alt="enter image description here" /></a></p>
  <p>Now the tutorial says this:</p>
  <pre><code>Step 4: Connect to the local runtime
  In Colaboratory, click the &quot;Connect&quot; button and select &quot;Connect to local runtime...&quot;. Enter the URL from the previous step in the dialog that appears and click the &quot;Connect&quot; button. After this, you should now be connected to your local runtime.
  </code></pre>
  <p>What do they mean by &quot;In Colaboratory&quot;?</p>
  <p>I have no idea what I should do.
  So I start typing &quot;colab&quot; in Chrome.</p>
  <p>It autosuggests:</p>
  <p><a href="https://colab.research.google.com/drive/1rI4RLP6rXXXXXXXXX" rel="nofollow noreferrer">https://colab.research.google.com/drive/1rI4RLP6rXXXXXXXXX</a></p>
  <p>I press enter, and Chrome loads this page. It looks like this:</p>
  <p><a href="https://i.stack.imgur.com/PezMs.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PezMs.png" alt="enter image description here" /></a></p>
  <p>When I press the down arrow and then &quot;Connect to local ressource&quot;, it says:</p>
  <p><a href="https://i.stack.imgur.com/Jtd17.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Jtd17.png" alt="enter image description here" /></a></p>
  <p>The token does not match the one in the command line, does it??</p>
  <p>If I then press &quot;Connect&quot; on the right button, it fails.</p>
  <p>Is the different token the reason?</p>
  <p>If yes, were am I going wrong?</p>
  <p>Thank you!</p>