title: Filebeat gives: object mapping for [error] tried to parse field [error] as object, but found a concrete value
body: <p>In elastic search i have created an ingest pipeline with the next grok pattern:</p>
  
  <pre><code>OK -%{DATA:label},%{INT:samples},%{BASE16FLOAT:average},%{BASE16FLOAT:min},%{BASE16FLOAT:max},%{BASE16FLOAT:p90},%{BASE16FLOAT:stddev},(?&lt;error&gt;([0-9].[0-9]*%)),
  </code></pre>
  
  <p>Simulating this with the next line: </p>
  
  <pre><code>OK - test,272,2275,593,14830,4581,1826.76,0.00%,.0,9.53,291717.4,30-04-2018 10:29:09 
  </code></pre>
  
  <p>works perfect in kibana.</p>
  
  <p>When i let filebeat indexing this file i get this error: <code>object mapping for [error] tried to parse field [error] as object, but found a concrete value</code> what goes wrong?</p>