title: Angular ng serve --host local ip suddenly doesn't work with my Mac
body: <p>I am using</p>
  <ul>
  <li>Mac Catalina 10.15.7</li>
  <li>Angular 11</li>
  </ul>
  <p>I used to accessing to my local network(local machine) with my Android mobile phone with</p>
  <pre><code>ng serve --host 192.168.31.65
  </code></pre>
  <p>I had accessed with my mobile to local machine many times. It WORKED many times correctly for long.</p>
  <p>But suddenly it doesn't work.</p>
  <p>The command works well.</p>
  <p><a href="https://i.stack.imgur.com/Hhnjg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Hhnjg.png" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/MdHcL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MdHcL.png" alt="enter image description here" /></a></p>
  <p>I tried with different laptops and two different mobile phones and they works well. So it is not a problem of codes and mobile phones.</p>
  <p>My conclusion is that it is a problem of my local machine.</p>
  <p>So I checked my firewall as below.</p>
  <p><a href="https://i.stack.imgur.com/IWVCb.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IWVCb.png" alt="enter image description here" /></a></p>
  <p>But I can't deactivate the firewall because of admin settings.</p>
  <p>Summary</p>
  <ul>
  <li><p>It worked well for long but suddenly didn't.</p>
  </li>
  <li><p>I tested with multiple different mobile phones but doesn't work, either.</p>
  </li>
  <li><p>But it works well if I use same mobile phones with different local machine(Window laptop)</p>
  </li>
  </ul>
  <p>What should I do now?</p>