title: Sync file permissions *only*
body: <p>A junior team member did a nasty <code>chmod -R 777</code> in <code>/etc/</code> and cause SSH cannot login remotely in a Ubuntu server. Now I fixed this login issue by manually set the correct file permissions on <code>/etc/ssh/*</code>, <code>/etc/sudoers</code>, <code>/etc/ssl/*</code> by comparing other normal system. But there are so many other files which may cause future issues.</p>
  
  <p>I am thinking to use rsync to do the work, but don't want it to sync file contents, just permissions, no more work.</p>
  
  <p>Is that possible? I see rsync has <code>-a</code> option but it does too much.</p>