title: Need dedicated Xvfb display for each jenkins job
body: <p>I need to run two jenkins' job  in parallel but when first one is running the second one fails stating that <code>Server is already active for display 0</code></p>
  
  <p>I have gone through these two posts but not able to fix:</p>
  
  <ol>
  <li><a href="https://stackoverflow.com/questions/43122174/xvfb-plugin-to-run-multiple-job-instances-concurrently-on-jenkins">Xvfb plugin to run multiple job instances concurrently on Jenkins</a></li>
  <li><a href="https://www.blazemeter.com/blog/headless-execution-selenium-tests-jenkins" rel="nofollow noreferrer">https://www.blazemeter.com/blog/headless-execution-selenium-tests-jenkins</a></li>
  </ol>
  
  <p>I have <code>export DISPLAY=:99</code> this line added in my <code>centos 7</code> profile. </p>
  
  <p>Also I have below configuration for XVFB in jenkins > </p>
  
  <p><strong>1. Manage jenkins > Configure System (Configure global settings and paths.)</strong>
  <a href="https://i.stack.imgur.com/xaT2l.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xaT2l.png" alt="enter image description here"></a> 
   <strong>2. And then in Job configuration I have:</strong>
  <a href="https://i.stack.imgur.com/2AtJg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/2AtJg.png" alt="enter image description here"></a>
  <a href="https://i.stack.imgur.com/vfHU0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/vfHU0.png" alt="enter image description here"></a></p>
  
  <p>Please let me know if I am missing anything. Thanks</p>