Installing an update

Now we want to make a change to the root filesystem and then install it as an update:

1. Open another shell and put yourself back in the working build directory:

   $ source poky/oe-init-build-env build-mender-qemu

2. Make a copy of the image we just built. This will be the live image that we are going to update:

   $ cd tmp/deploy/images/vexpress-qemu
   $ cp core-image-full-cmdline-vexpress-qemu-grub.uefiimg \
   core-image-live-vexpress-qemu-grub.uefiimg 
   $ cd -

   If we don't do this, the QEMU script will just load the latest image generated by BitBake, including updates, which defeats the object of the demonstration.

3. Next, change the hostname of the target, which will be easy to see when it is installed. To do this, edit conf/local.conf and add this line:

   hostname_pn-base-files = "vexpress-qemu-release2"

4. Now we can build the image in the same way as before:

   $ bitbake core-image-full-cmdline

   This time we are not interested in the .uefiimg file, which...