Building Custom Linux Distros.md

tags
embeddedLinux yocto

Building Custom Linux Distros

A unique feature of Yocto is the ability to build custom Linux distros. A distro layer is a powerful abstraction that can be shared across multiple projects targeting different hardware. Creating a distro helps alter policies such as C library implementations and choice of package managers. Building a distro is a three step process:

1. Create a new distro layer. A new distro is created as a Yocto layer.

# Create a build
source poky/oe-init-build-env <build>

# Create a new layer for the distro
bitbake-layers create-layer ../meta-<distro>

# Add layer to build
bitbake-layers add-layer ../meta-<distro>

2. Create a distro configuration file. For this, create. distro configuration file in the meta-<distro> directory at conf/distro with the name <distro>.conf. Set the required variables and any optional ones as necessary:

# Mandatory:
DISTRO_NAME =
DISTRO_VERSION =

# Optional
DISTRO_FEATURES = # Add softwaresupport for these features.
DISTRO_EXTRA_RDEPENDS = # Add these packages to all images.
DISTRO_EXTRA_RRECOMMENDS = # Add these packages if they exist.
TCLIBC = # Select this version of the C standard library.

Once this is done, use the conf/local.conf file to define any more variables.

3. Add recipes to the distro. This can be done using [[devtool]] or manually