nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use) even after killing the process using port 80
<p>I'm trying to start nginx as follows:</p>

<pre><code>kurt@kurt-ThinkPad:~$ which nginx
/usr/sbin/nginx
kurt@kurt-ThinkPad:~$ sudo /usr/sbin/nginx
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] still could not bind()
</code></pre>

<p>Following this <a href="https://easyengine.io/tutorials/nginx/troubleshooting/emerg-bind-failed-98-address-already-in-use/" rel="nofollow noreferrer">EasyEngine tutorial</a>, I tried to kill the process using port 80 with <code>fuser -k</code>:</p>

<pre><code>kurt@kurt-ThinkPad:~$ sudo fuser -k 80/tcp
80/tcp:              31924 31925 31926
</code></pre>

<p>However, after re-running <code>sudo /usr/sbin/nginx</code> I get exactly the same error message.</p>

<p>I've tried a couple of other 'diagnostics' described <a href="https://www.cyberciti.biz/faq/find-linux-what-running-on-port-80-command/" rel="nofollow noreferrer">here</a>, using <code>fuser</code>, <code>lsof -i</code>, and <code>netstat</code>:</p>

<pre><code>kurt@kurt-ThinkPad:~$ fuser 80/tcp
kurt@kurt-ThinkPad:~$ lsof -i :80 | grep LISTEN
kurt@kurt-ThinkPad:~$ netstat -tulpn | grep --color :80
(Not all processes could be identified, non-owned process info
 will not be shown, you would have to be root to see it all.)
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      -               
tcp        0      0 127.0.0.1:8080          0.0.0.0:*               LISTEN      -               
tcp        0      0 0.0.0.0:8060            0.0.0.0:*               LISTEN      -      
</code></pre>

<p>Only the <code>netstat</code> command gives a result, but I wasn't able to infer a process ID from it.</p>

<p>Any ideas on how to get nginx to work?         </p>