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 # extroot
 
-Expand the router's storage space, from few MB to several GB
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+Expand the router's storage space, from few MB to several GB, by using a USB storage device.
+
+`extroot` implies moving the router's overlay partition to this external USB device 
+
+* Minimal requirements: `kmod-usb-storage kmod-fs-ext4 block-mount` 
+* Extended functionalities: `e2fsprogs fdisk lsblk cryptsetup kmod-crypto-ecb kmod-crypto-misc kmod-crypto-sha512 kmod-crypto-user kmod-crypto-xts kmod-loop kmod-fs-isofs`
+
+What this script should be doing:
+
+* check minimal packages
+* find usb & fetch overlay uuid
+* mount uuid, clean partition, copy files from device's overlay
+* check uci config, adjust accordingly
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