title: Prevent multiple instances of an Azure web job processing the same Queue message
body: <p>I noticed that multiple instances of my Web job are receiving the same message and end up acting on it. This is not the desired behavior. I would like multiple messages to be processed concurrently, however, I do not want the same message being processed by multiple instances of the web job.</p>
  <ul>
  <li>My web job is of the continuous running type.</li>
  <li>I use a QueueTrigger to receive the message and invoke the function</li>
  <li>My function runs for several hours.</li>
  </ul>
  <p>I have looked into the JobHostConfiguration.BatchSize and MaxDequeue properties and I am not sure on these. I simply want a single instance processing a message and that it could take several hours to complete.</p>
  <p>This is what I see in the web job logs indicating the message is received twice.</p>
  <blockquote>
  <p>[01/24/2017 16:17:30 &gt; 7e0338: INFO] Executing:
  'Functions.RunExperiment' - Reason: 'New queue message detected on
  'runexperiment'.'</p>
  <p>[01/24/2017 16:17:30 &gt; 7e0338: INFO] Executing:
  'Functions.RunExperiment' - Reason: 'New queue message detected on
  'runexperiment'.'</p>
  </blockquote>