Recovering files from the "other" boot partition

mariano.silva · June 20, 2017, 11:40am

Hi everyone!

After updating several packages last night, the partition of my WRT1900ACS did not boot anymore ... it took a while and then it booted from the other partition... problem is that I've tried to manually set it to boot from the original one and keeps doing the same thing, reverting back to the secondary partition.

Real problem is that I had some files that I need in that other partition , in the /root folder ( several .sh files ) ... is there a way to recover them ( maybe using dd ) ?

hnyman · June 20, 2017, 12:46pm

You can use /tmp/syscfg directory to share/move files between the two boot partitions. It is visible from both.

But there is no easy way to get files directly from the other partition. You have to switch boot first.
One easy tool is e.g. https://github.com/stangri/openwrt-luci/blob/luci-app-advanced-reboot/applications/luci-app-advanced-reboot/README.md from stangri.

Direct download of the ipk package:
https://github.com/stangri/openwrt-repo/blob/master/luci-app-advanced-reboot_git-17.152.82962-a9e8376-11_all.ipk

mariano.silva · June 20, 2017, 1:06pm

I've installed the advanced-reboot ... and the result is the same, it will
boot to the alternative partition, fail the boot, and revert back to the
partition I don't want to use

Any way to use dd to find the files I'm looking for?

eduperez · June 20, 2017, 4:07pm

I just had a look at how the memory is configured in these devices (https://wiki.openwrt.org/toh/linksys/wrt_ac_series#flash_storage_layout).
Files that you created after installing LEDE should be on the overlay partition.
Now, that partition is on /dev/ubi0_1 in my device (similar to yours).
There exists also a /dev/ubi0_0, but I was not capable of mounting it.
There is a document explaining the booting process at https://wiki.openwrt.org/doc/techref/process.boot, that could shed some light on how to mount it.

DjiPi · June 20, 2017, 4:26pm

Maybe if you force a reboot on this failing partition and use the failsafe mode to get ssh access you will be able to get at least a console access? Maybe that way the partition will be mounted and accessible, so less fuss trying to get the files from there.

https://lede-project.org/docs/user-guide/failsafe_and_factory_reset#entering_failsafe_mode

mariano.silva · June 23, 2017, 8:18am

Thank you guys... I've tried everything, and my "other" partition wouldn't boot... even using @eduperez suggestion to go into "Failsafe mode".

Before I upgrade my only working partition now, how can i restablish the non-working one ( that I don't have access to boot from ) to a working order? I don't want to be stranded with just one working partition....

hnyman · June 23, 2017, 11:38am

You always flash the other partition. If you run sysupgrade in the current ok partition, it actually flashes the other partition and switches boot to that. The current one remains unchanged.

mariano.silva · June 23, 2017, 12:07pm

Got it, thanks! It worked fine

Saludos,
Mariano