title: Rabbitmq File Descriptor Limit
body: <p>Rabbitmq documentation says that we need to do some configuration before we use it on production. One of the configuration is about maximum open file number (which is an OS parameter).</p>
  
  <p>Rabbitmq server we use is running on Ubuntu 16.04 and according to resources I found on web, I updated the number of open files as 500k. When I check it from command line, I get the following output:</p>
  
  <pre><code>root@madeleine:~# ulimit -n
  500000
  </code></pre>
  
  <p>However when I look at the rabbitmq server status, I see another number.</p>
  
  <pre><code>root@madeleine:~# rabbitmqctl status | grep 'file_descriptors' -A 4
   {file_descriptors,
       [{total_limit,924},
        {total_used,19},
        {sockets_limit,829},
        {sockets_used,10}]},
  </code></pre>
  
  <p>It seems like, I managed to increase the limit on OS side, but rabbitmq still thinks that total limit of file descriptors is 924.</p>
  
  <p>What might be causing this problem?</p>