title: Revert to original configuration in Jenkins
body: <p>I have a Jenkins server hosted, which has a master node and couple of other slave configurations. Last night, the job that triggers the matrix based build configuration failed. I did a restart and performed clean up jobs via Jenkins but none of those fixed the issue. The initial error that was logged was:</p>
  
  <p><code>FATAL: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected termination of the channel
  hudson.remoting.RequestAbortedException: hudson.remoting.RequestAbortedException: java.io.IOException: Unexpected termination of the channel</code></p>
  
  <p>Following which I performed a reload configuration from disk,followed by a manual restart via <code>&lt;jenkins_job_url&gt;/restart</code>, which even worsened the build system. The master went offline due to unavailability of space in <code>/tmp</code> folder, which I fixed by cleaning up the space. Following which I observed that the original slave server configuration is no longer seen. I had slave-0 and slave-1 still there, but slave-2 was no longer present. Instead, it got replaced with slave-3 configuration. Now the slave 0's and 1's seems to be working fine. However, slave 3's build are failing due to <code>Failed to mkdirs</code>. Is there a way I could revert back to the original configuration from where I started, since the steps I performed seems to make sense initially, but I had no idea it had so many repercussions? Any help is appreciated.</p>
  
  <p>UPDATE1: I guess I should have used some of the configuration backup plugins available in Jenkins, but is there some specific directory other than $JENKINS_HOME where these configurations gets stored?</p>