Hi Team,
How to implement recovery as like android devices when kernel corrupted and the device fails to boot.
Any pointers to begin with?
Thanks,
Arun
Hi Team,
How to implement recovery as like android devices when kernel corrupted and the device fails to boot.
Any pointers to begin with?
Thanks,
Arun
Any idea on this?
Thanks,
Arun
Recovery in Android is basically a second OS that can be switched to by a special bootloader mode controlled by a hardware key. Typically the bootloader supports normal boot, recovery boot and fastboot. I suspect if you review the LittleKernel source code you will find the code (currently unused) that implements this.
I am able to create recovery partition and enter recovery boot from lk. How to update the corrupted boot partition with recovery partition? for DB410c, I can see DragonBoard 410c Board Recovery - 96Boards SDcard recovery image which will update the corrupted partitions. How to create a similar image for DB820c? my idea is to build a similar image for recovery boot for DB820c and that will update all the corrupted partitions if i boot into recovery mode.
Thanks,
Arun
SD card recovery is not supported on DB820C. I’m not 100% certain but IIRC this is because there is not a working SD card driver for this platform in LittleKernel.
@danielt
yes, there is no SDcard driver for DB820c. my intention is to ask how to create a recovery image and what recovery image should contain for DB820c?
I want to implement like this:
if I make a boot in recovery mode, from recovery mode it should update corrupted partitions(example: boot partition) and boot back in normal mode. Any pointers to create recovery image to do this?
Thanks,
Arun
The recovery image is simply a regular userspace that automatically starts a service to rewrite the partitions. As it happens the DB410C recovery images are customised Debian images (mostly to reduce maintenance costs by using a similar userspace for recovery and for normal running).
I have built recovery image(contains boot image+initrd.img), initrd.img has the scripts to rewrite the partitoins and flashed it in recovery partition, lets say as sde3. In script, i am using simple copy command to copy corrupted boot partition(ex: sde2) with backup boot partition(ex: sde1) (cp sde1 sde2). with this, I am able to recover the corrupted boot partition.
Is this a proper way?
@danielt
Thanks,
Arun
Personally I would have used dd but I doubt the choice of copy tool matters very much.
… although for big images such as rootfs you should use something like simg2img or bmap-tools to make the writing process quicker.