title: Jenkins failed to launch the slave agent
body: <p>I am trying to launch new slave agent but I am seeing the below error. Can you please help in resolving this. 
  - I have copied the keys in both the machines in .ssh/authorized_keys and able to connect manually but failing from jenkins.
  - All permissions also looks gud.</p>
  
  <pre><code>[02/19/16 13:12:34] [SSH] Opening SSH connection to sdc-caoneops-    app1.qa.xxxxx.com:22.
  ERROR: Server rejected the 1 private key(s) for App (credentialId:6aced962-  26cd-4c8f-97d3-305c2e2a6540/method:publickey)
  [02/19/16 13:12:34] [SSH] Authentication failed.
  hudson.AbortException: Authentication failed.
  at hudson.plugins.sshslaves.SSHLauncher.openConnection(SSHLauncher.java:1178)
  at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:701)
  at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:696)
  at java.util.concurrent.FutureTask.run(FutureTask.java:266)
  at    java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
  at java.lang.Thread.run(Thread.java:745)
  [02/19/16 13:12:34] Launch failed - cleaning up connection
  [02/19/16 13:12:34] [SSH] Connection closed.
  </code></pre>