Failing typo in Extroot configuration

Talk about Documentation
1

Hi all, I don't have write access to the wiki, but I'd like to get a modification done that is failing the procedure.

change

eval $(block info ${DEVICE} | grep -o -e 'UUID="\S*"')

by

eval $(block info ${USBDEVICE} | grep -o -e 'UUID="\S*"')

change

mount ${DEVICE} /mnt
tar -C ${MOUNT} -cvf - . | tar -C /mnt -xf -
reboot

by

mount ${USBDEVICE} /mnt
tar -C ${MOUNT} -cvf - . | tar -C /mnt -xf -
reboot
2

Can you elaborate as to why you think this change should be made? Specifically, DEVICE is just a variable name (defined in the first line of code in section 2 of the page you linked). Changing this to USBDEVICE should have no effect (positive or negative)... unless I'm missing something?

When I run the following line of code:

DEVICE="$(block info | sed -n -e '/MOUNT="\S*\/overlay"/s/:\s.*$//p')"

I end up with valid output:

root@openwrt:~# echo $DEVICE
/dev/sda1
3

I guess it works for you because you have already implemented extroot. For the virgin device, DEVICE is /dev/ubi0_1 and USBDEVICE is /dev/sda1

4

Gottcha. I wonder if this issue is specific to UBI devices... it may not impact others. This would need a bit of checking. The other question would be if there is ever a situation where the DEVICE variable would be different than USBDEVICE and thus important for the functioning of the script.

5

my device is WRT1900ACv2, and the current version of the doc would make me reboot with a weird setting, lucky I've double checked

# block info
/dev/ubiblock0_0: UUID="80a00b43-db031c31-63d845ef-5891455e" VERSION="4.0" MOUNT="/rom" TYPE="squashfs"
/dev/ubi0_1: UUID="7080715f-ae28-48bc-afb4-09d5b040ee5d" VERSION="w5r0" MOUNT="/overlay" TYPE="ubifs"
/dev/ubi1_0: UUID="5ed23499-15d0-4097-a301-28867bbdf15b" VERSION="w4r0" TYPE="ubifs"
/dev/sda1: UUID="b2d5064c-a275-4dfb-9c0d-d8a471552118" LABEL="extroot" VERSION="1.0" TYPE="ext4"

# mount ${DEVICE} /mnt
mount: mounting /dev/ubi0_1 on /mnt failed: Block device required

# block info ${DEVICE} | grep -o -e 'UUID="\S*"'
--> Empty

# block info | sed -n -e '/MOUNT="\S*\/overlay"/s/:\s.*$//p'
/dev/ubi0_1
6

The documentation has been updated.

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