Merge pull request #2037 from Chris-Peterson444/kernel-cloud-refresh-…

…docs

docs: add reference examples for kernel, user-data, and refresh-installer

doc/reference/autoinstall-reference.rst

@@ -139,6 +139,23 @@ channel
 
 The channel to check for updates.
 
+Example:
+
+.. code-block:: yaml
+
+  autoinstall:
+   # Refresh to the latest snap built from the "main" subiquity branch
+   refresh-installer:
+     update: true
+     channel: latest/edge
+
+  autoinstall:
+   # Refresh to the latest beta release
+   refresh-installer:
+     update: true
+     channel: latest/beta
+
+
 .. _ai-keyboard:
 
 keyboard
@@ -728,6 +745,8 @@ Several tools can generate the encrypted password, such as ``mkpasswd`` from the
 
 Example:
 
+.. _ai-identity-example:
+
 .. code-block:: yaml
 
     autoinstall:
@@ -944,6 +963,8 @@ kernel
 
 Which kernel gets installed. Either the name of the package or the name of the flavour must be specified.
 
+The exact default kernel is ISO build specific, but generally the ``generic`` flavour is installed for Server and the ``hwe`` flavour is installed for Desktop.
+
 package
 ^^^^^^^
 
@@ -958,6 +979,20 @@ flavor
 
 The ``flavor`` of the kernel, e.g., ``generic`` or ``hwe``.
 
+Example:
+
+.. code-block:: yaml
+
+   autoinstall:
+      # Install a specific kernel package.
+      kernel:
+        package: linux-image-5.13.0-40-generic
+
+   autoinstall:
+      # Install a particular kernel flavour.
+      kernel:
+        flavour: hwe
+
 .. _ai-timezone:
 
 timezone
@@ -1107,4 +1142,18 @@ user-data
 * **default:** ``{}``
 * **can be interactive:** no
 
-Provide cloud-init user data, which will be merged with the user data the installer produces. If you supply this, you don't need to supply an :ref:`identity section <ai-identity>` (in that case, ensure you can log in to the installed system).
+Provide cloud-init user data, which will be merged with the user data the installer produces. If you supply this, you don't need to supply an :ref:`identity section <ai-identity>` (in that case, ensure you can log in to the installed system). For more details on cloud-init user-data, see :doc:`cloud-init:reference/examples`.
+
+The following example provides user-data which is approximately equivalent to what is generated by the configuration in the :ref:`identity section example<ai-identity-example>`:
+
+.. code-block:: yaml
+
+  autoinstall:
+    user-data:
+       users:
+         - name: ubuntu
+           gecos: 'Ubuntu User'
+           passwd: '$6$wdAcoXrU039hKYPd$508Qvbe7ObUnxoj15DRCkzC3qO7edjH0VV7BPNRDYK4QR8ofJaEEF2heacn0QgD.f8pO8SNp83XNdWG6tocBM1'
+           groups: adm, cdrom, dip, lxd, plugdev, sudo
+           shell: /bin/bash
+           lock_passwd: False