Using bootspec with RAUC and redundant partitions

[Sascha Hauer]

Hi Robin,

On Tue, Sep 29, 2020 at 03:02:15PM +0200, robin wrote:
> Hi All,
> 
> Can anyone help me determine where to place the bootspec data in a system
> with redundant partitions for kernel and rootfs?
> 
> We're migrating from scripts in env/boot for 'system0' and 'system1', to
> bootspec. We're using bootchooser combined with the state framework to
> determine
> which target needs to be booted.
> 
> Our partition table (relevant partitions):
>  mmc2.0: kernel.0
>  mmc2.1: kernel.1
>  ...
>  mmc2.4: rootfs.0
>  mmc2.5: rootfs.1
> 
> Looking into the bootspec, we could add an additional 'boot' partition but
> this breaks redundancy, and feels trivial since we have the kernel partitions.

Yes, I wouldn't add an additional boot partition.

> 
> But adding the loader/entries to the kernel partitions probably requires us
> to generate them runtime (Rauc post-install?). Since Rauc determines which
> kernel partition will be written with the contents of 'kernel' image in a bundle
> the bootspec can't be determined at build time.
> 
> Is there a door number 3 or am I missing something here?

What's the reason for additional kernel partitions? Things would be
easier if you put the kernel images into the rootfs partitions along
with the bootspec entries.

Sascha

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