Update some documentation for the v0.3.0 release

CHANGELOG.md

@@ -1,14 +1,17 @@
 # Changelog
 
-## v0.3.0 (unreleased)
+## v0.4.0 (unreleased)
+
+ - Ignite now uses Devicemapper's `thin-provisioning` feature, for way better performance and added capabilities.
+
+## v0.3.0
 
 Major release with significant UX and internal improvements:
 
- - There is no longer a difference between an Ignite image and an OCI image, this is now the same thing. Ignite operates on OCI images
-   directly, for both OS images and kernels.
- - Ignite now uses Devicemapper's `thin-provisioning` feature, for way better performance and added capabilities.
+ - There is no longer a difference between an Ignite image and an OCI image, this is now the same thing.
+     - Ignite operates on OCI images directly, for both OS images and kernels. The kernel is expected to be coupled with the image given to `ignite run`, in `/boot/vmlinux`.
  - It is now possible to do `ignite run [OCI image]` directly, and everything (e.g. pulling the image) is handled automatically. e.g. `ignite run -i weaveworks/ignite-ubuntu`.
- - Now `ignite images` shows OCI images that are cached and ready to use, and `ignite kernels` the kernel images ready to use.
+ - Now `ignite images` shows OCI images that are cached and ready to use, and `ignite kernels` the kernels already imported from base images.
  - Added an example usage guide for running a Kubernetes cluster in HA mode using kubeadm and Ignite.
  - Removed `ignite build`, and `ignite image/kernel import`; as these are no longer needed
  - Importing an image from a tROADMAPar file is no longer possible, package the contents in an OCI image instead

README.md

@@ -53,7 +53,7 @@ for certain specific operations (e.g. `mount`). This will change in the future.
 
 ```bash
 # Let's run the weaveworks/ignite-ubuntu docker image as a VM
-# Use 2 vCPUs and 1GB of RAM, enable SSH access and name it my-vm
+# Use 2 vCPUs and 1GB of RAM, enable automatic SSH access and name it my-vm
 ignite run weaveworks/ignite-ubuntu \
     --cpus 2 \
     --memory 1024 \
@@ -91,16 +91,26 @@ ignite rm my-vm
 
 See the [CLI Reference](docs/cli/ignite.md).
 
-### Sample Images
+### Base images and kernels
+
+A _base image_ is an OCI-compliant image containing some operating system (e.g. Ubuntu).
+You can follow normal `docker build` patterns for customizing your VM's rootfs.
+
+A _kernel binary_ is today expected to be inside of the rootfs, at `/boot/vmlinux` (may
+be a symlink). It is also recommended to put supported kernel modules in `/lib/modules`
+if you need that. Today we couple the kernel and the base image, this will however change
+in future releases so you can mix and match kernel and base image OCI-images at `ignite run`-time.
 
 As the upstream `centos:7` and `ubuntu:18.04` images from Docker Hub doesn't
-have all the utilities and packages you'd expect in a VM, we have packaged some
+have all the utilities and packages you'd expect in a VM (e.g. an init system), we have packaged some
 reference base images and a sample kernel image to get started quickly.
 
- - [Kernel Builder Image](images/kernel/Dockerfile)
- - [Ubuntu 18.04 Dockerfile](images/ubuntu/Dockerfile)
- - [CentOS 7 Dockerfile](images/ubuntu/Dockerfile)
- - [Guide: Run a HA Kubernetes cluster with Ignite and kubeadm](images/kubeadm)
+ - [Kernel Builder Image](images/kernel/Dockerfile) (`weaveworks/ignite-centos`)
+ - [Ubuntu 18.04 Dockerfile](images/ubuntu/Dockerfile) (`weaveworks/ignite-ubuntu`)
+ - [CentOS 7 Dockerfile](images/ubuntu/Dockerfile) (`weaveworks/ignite-kernel`)
+ - [Guide: Run a HA Kubernetes cluster with Ignite and kubeadm](images/kubeadm) (`weaveworks/ignite-kubeadm`)
+
+These prebuilt images can be given to `ignite run` directly.
 
 ### Known limitations