title: rsync'ing files between two remote servers, get errors stating rsync command not found on remote server
body: <p>I'm trying to rsync files between two servers with </p>
  
  <pre><code>rsync -avlzp /source user@server:/destination
  </code></pre>
  
  <p>but instead I get errors stating</p>
  
  <pre><code>bash: rsync: command not found
  rsync: connection unexpectedly closed (0 bytes received so far) [sender]
  rsync error: error in rsync protocol data stream (code 12) at io.c(635) [sender=3.0.2]
  </code></pre>
  
  <p>but rsync <strong><em>is</em></strong> installed on both servers.  What am I doing wrong?  I've also tried</p>
  
  <pre><code>rsync -av -e "ssh -l ssh-user" /source server:/destination
  </code></pre>
  
  <p>with the same result.</p>
  
  <p>I'm mainly trying to use rsync so that it only copies over differences if they exist...</p>
  
  <p>Thanks</p>