Instructions about Extroot don't seem to work

Installing and Using OpenWrt
1

Hello,

I’m trying to install extroot with the instructions on https://openwrt.org/docs/guide-user/additional-software/extroot_configuration but it does not seem to work:

  • ‘Configuring extroot’: $MOUNT is not set when issuinguci set fstab.extroot.target="${MOUNT}"
  • ‘Configuring rootfs_data / ubifs’: ORIG="$(block info | sed -n -e '/MOUNT="\S*\/overlay"/s/:\s.*$//p')" returns a clear string

Is there any place where I can find up-to-date instructions on how to create a USB extroot partition?

2

I've done this many many times, but I actually use a slightly different recipe without the variables.

See my recipe here. Let me know if that works for you.

3

@psherman thanks for your help. I issued your command, which sadly didn't work either. But that did push me into investigating this a bit more. I managed to fix it after all. It probably had something to do with file space; I think that my custom Openwrt image flashed successfully but it didn’t keep its settings after reboots.

What I did: I created a custom image using the Openwrt Firmware Selector, but instead of adding the packages block-mount kmod-fs-ext4 e2fsprogs parted kmod-usb-storage I added only block-mount kmod-fs-ext4 kmod-usb-storage since the USB stick was already prepared. This saved some space on the image.

Then I went to System > Mount Points in Luci, clicked on Edit next to the USB drive in 'Mount Points'. I chose / as the mount point and executed the commands that showed op:

mkdir -p /tmp/introot
mkdir -p /tmp/extroot
mount --bind / /tmp/introot
mount /dev/sda1 /tmp/extroot
tar -C /tmp/introot -cvf - . | tar -C /tmp/extroot -xf -
umount /tmp/introot
umount /tmp/extroot

Then I saved, applied and rebooted, and that was all.

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