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 # backup-script
 Bash script to create squashfs compressed archives of block device images.
+
+This script will generate an image file of the backup destination
+and add it to a squash compressed filesystem.
+
+# Why
+I like doing full disk backups from time to time. This way I can't miss
+any important files. Moreover this also backups the complete partition layout and
+LUKS Headers if they exists on a system.
+The problem is full disk images can get quite big, even if there is not much space
+used on the disk. Therefore compressing images does make sense. However by simply
+gzipping images one is not be able to simply mount the image in case access to a
+single file is needed.
+By using squashfs this is circumventet.
+The squashfs can be mounted in a compressed state being completly transparend
+to the user (besides being read-only).
+When the squasfs is mounted the # Usage
+```bash
+# ./backup.sh
+Backup source: /dev/sda1
+Backup destination: /mnt/backupOfsda1
+```
+image file can be mounted as if it existed
+uncompressed. By again mounting the image file (using e.g. loopback devices)
+it is possible to access browse/access single files inside the compressed
+full disk backup.
+
+This script was created because I could not remember the commands used to create
+such a compressed image and got tired of searching every time.