title: How to make a tar backup of a root filesystem?
body: <p>I have linux installed on SD card, I used this command to install the rootfs</p>
  
  <p>tar xpjf rootfs.tar.bz -C /mnt/rootfs/</p>
  
  <p>Now, I made some changes to the rootfs and I would like to create a backup that I can use with the same command above, I tried using:</p>
  
  <pre><code>tar cpjf rootfs.tar.bz2 /mnt/rootfs
  and
  tar cpjf rootfs.tar.bz2 -C / mnt/rootfs
  I also tried
  tar cpjf rootfs.tar.bz2 /mnt/rootfs/*
  </code></pre>
  
  <p>And tried:</p>
  
  <pre><code>cd /mnt/rootfs
  tar -cvpjf rootfs.tar.bz2 --exclude=/rootfs.tar.bz2 .
  tar: ./rootfs.tar.bz2: file changed as we read it
  </code></pre>
  
  <p>but I end up with an archive that has two levels before the file system i.e mnt/rootfs/files What am I doing wrong ?</p>