title: error in restoring the openwrt settings
body: <p>I want to restore the <code>openwrt</code> settings but this error keeps appearing :</p>
  
  <pre><code>Could not open mtd device: rootfs
  </code></pre>
  
  <p>I tried </p>
  
  <pre><code>firstboot
  mount_root
  mtd -r erase rootfs_data
  </code></pre>
  
  <p>eveything fails to access the rootfs file
  how to restore this file or I have to re-burn the openwrt files on the sdcard</p>