I wish to use the rootFS redundancy feature but there are few points left unclear to me:
- I read the following sentence in the dev guide:
As a failover mechanism, if the current active rootfs were damaged or corrupted, and then can’t boot up the system, after automatically rebooting 3 times (customizable), the device will failover to the other available unused rootfs to boot up. If both rootfs A and B are unbootable, the device will boot into the recovery kernel image.
My question is why I need an additional rootFS if I have a recovery kernel image available?
Maybe I don’t understand the meaning of “recovery kernel image”:
- Does it provides a “rescue” shell prompt enabling me modifying the corrupted rootfs?
- Does it contains the needed “basic” binaries for me to modify the corrupted rootfs, or maybe I can use the ones existing on that corrupted rootfs (its /bin , /sbin directories)?
Can I use different “types” of rootfs for my A/B rootfs? for example rootfs A will be the sample one and rootfs B will be a minimal one without a GUI?
Can I access (root priviliges) the rootfs files that is not being loaded? (the system booted with rootfsA and I use root account to access rootfsB internal files)
I read this line:
The Bootloader Update Payload (BUP) is the payload that is applied by the update engine during an update
and my question is why I need some special bootloader update mechanism if I can just update my bootloader image on my host and flash it directly to its partition using the flash.sh script or the initrd method.