[BPi-R3] Rescue bricked configuration - How to mount SDCARD on computer?

Banana Pi BPI-R4/BPI-R3 Mini/BPI-R3/BPI-R64/BPI-R2
1

I installed OpenWRT 23.05.0 to a SDCARD. Then I modified some config files, and now it refuses to boot :frowning: How can I mount the SDCARD on my computer to fix the config files? I see mmcblk0 with many partitions, but my computer doesn’t recognize any filesystems.

2

Is you computer a linux host? Windows will not be able to view linux specific filesystems

3

Yes it’s Debian.

I found this: BPi-R64-V1.1 OpenWRT Image expansion

mmcblk0p65 and mmcblk0p66 are virtual partitions defined by the uImage.FIT structure. You can’t edit them. If you want to increase the size of the overlay, you need to resize the production partition which is mmcblk0p4 (on eMMC) or mmcblk0p5 (on SD Card), they should also show up in parted.

On my computer “production” is mmcblk0p7. I think my problem is that my computer doesn’t know how to parse it and find the mmcblk0p65 and mmcblk0p66 partitions.

4

As your linked text says mmcblk0p6x are virtual partitions and created on the fly with data (e.g. file) on another partition. Afaik openwrt uses a squashfs,but if this is loaded/written to file idk

5

I managed to mount it now by searching for the f2fs filesystem, but I think there is a better way to do this. Still, maybe this is helpful for someone else.

env - grep --text --byte-offset --only-matching -P '\0{1024}\x10\x20\xF5\xF2' /dev/mmcblk0p7
losetup -o 10956800 --show -f /dev/mmcblk0p7
mount /dev/loop1 /mnt/openwrt
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