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I have been using a persistent mode USB when the hard disk of my laptop crashed. I like to mount the USB files on another computer running Ubuntu 12.10. From what I found after internet search, the file system is saved as squashfs file. The only squashfs file was /casper/filesystem.squashfs . I mounted this file using disks application (it used /dev/loop0 device ). However, I could not find the files that I had saved while running from the USB.

The files were saved in /home/ubuntu/Downloads. The mounted filesystem has no folder under the home directory. What should I do to retrieve the file on this computer. I do not have the permission to reboot this computer from the persistent USB. I just need the files saved inside the persistent file.

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up vote 6 down vote accepted

filesystem.squashfs is mounted read only. The files you have modified/created are written to casper-rw. Mount it with:

mkdir /tmp/casper
sudo mount -o loop /path/to/casper-rw /tmp/casper
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In newer versions of Ubuntu, USBs are automatically mounted to /media/<user>/<drive-label>/casper-rw – IQAndreas Jun 19 '14 at 15:58

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