Now that we know how a layer works, we can add an existing external layer to our environment. To do this, we'll be working with meta-webserver ( http://layers.openembedded.org/layerindex/branch/master/layer/meta-webserver/ ) in order to include the famous web server, Monkey (http://monkey-project.com/).
As you know, the first step consists of modifying our conf/bblayers.conf file in order to add the path of the layer, as follows:
# LAYER_CONF_VERSION is increased each time
build/conf/bblayers.conf
# changes incompatibly
LCONF_VERSION = "6"
BBPATH = "${TOPDIR}"
BBFILES ?= ""
BBLAYERS ?= " \
/home/packt/RASPBERRYPI/poky/meta \
/home/packt/RASPBERRYPI/poky/meta-yocto \
/home/packt/RASPBERRYPI/poky/meta-yocto-bsp \
/home/packt/RASPBERRYPI/poky/meta-raspberrypi \
/home/packt/RASPBERRYPI/poky/meta-openembedded/meta-webserver \
"
BBLAYERS_NON_REMOVABLE ?= "...