title: backing up entire linux server on external hard drive or another cluster
body: <p>We have a linux server for the database. Most of our data are on /var/. I would like to backup entire directory on external hard drive or on another linux system so that if something goes wrong I can entirely replace the directory. Since the directory has many files, I do not want to copy and paste every time instead I like to sync them. </p>
  
  <p>Is there easy way to do that? rsyn can do that, how do I avoid of login every time the server? BTW I have limited knowledge of linux system. </p>
  
  <p>Appreciated any comments and suggestions.</p>
  
  <p>Bikesh</p>