[yocto] Creating multiple filesystem images

[Andre McCurdy]

On Mon, Aug 13, 2018 at 8:23 AM, Amol Lad <Amol.Lad at 4rf.com> wrote:
> Hi,
>
> Currently when we build say core-image-minimal, we get a root file system
> image (say ext4) after the build. However, I also need to create an ext4
> image for /boot partition (which contains zImage and dtb). I do not want wic
> image. How I can do this? i.e. I want two ext4 images after build: one root
> file system and another with content of /boot folder. Please advise

This isn't supported directly. However, if you look in
meta/classes/image_types.bbclass -> oe_mkext234fs() you will find the
commands which are run for the ext4 image type.

By copying and extending that code, you can define your own custom
image type (e.g. "ext4-split") which creates two ext4 images from the
rootfs instead of one.