title: Error: index_not_found_exception
body: <p>I use ELK stack to analyze my log file. I have tested last week and everything works well.</p>
  
  <p>Today, I tested but I get this error when I typed "<a href="http://localhost:9200/iot_log/_count" rel="noreferrer">http://localhost:9200/iot_log/_count</a>" (iot_log is my index pattern):</p>
  
  <blockquote>
    <p>{"error":{"root_cause":[{"type":"index_not_found_exception","reason":"no
    such
    index","resource.type":"index_or_alias","resource.id":"iot_log","index_uuid":"<em>na</em>","index":"iot_log"}],"type":"index_not_found_exception","reason":"no such
    index","resource.type":"index_or_alias","resource.id":"iot_log","index_uuid":"<em>na</em>","index":"iot_log"},"status":404}</p>
  </blockquote>
  
  <p>I really searched the forums but I have not found a solution, I want to know what is the cause of this problem please and how can I correct it?</p>