doc: de-duplicate instructions in kind and hubble getting started guides

These 2 guides have a lot of instructions in common as the Hubble guide
instructs to create a sandbox environment using Kind. This commit
ensures that instructions are not duplicated in the two guides but are
included from separate files from the 2 guides.

In addition to this, this commit also updates the instructions about
possible conflict of IP address when deploying a cluster with Kind: the
"tip" has been moved to the "Configure Kind" section as the fix needs to
be applied when configuring Kind.

Moreover, remove the "Optional" wording with regard to pre-loading the
cilium image into the Kind cluster.

Signed-off-by: Robin Hahling <robin.hahling@gw-computing.net>

Documentation/gettingstarted/hubble.rst

@@ -22,24 +22,14 @@ across the globe, there is almost always someone available to help.
 
 .. include:: kind-install.rst
 
-.. note::
-   The cluster nodes will remain in state ``NotReady`` until Cilium is deployed.
-   This behavior is expected.
-
 Deploy Cilium and Hubble
 ========================
 
 .. include:: k8s-install-download-release.rst
+.. include:: kind-preload.rst
 
-**(optional, but recommended)** Pre-load Cilium images into the kind cluster so
-each worker doesn't have to pull them.
-
-.. parsed-literal::
-
-  docker pull cilium/cilium:|IMAGE_TAG|
-  kind load docker-image cilium/cilium:|IMAGE_TAG|
-
-Install Cilium release via Helm:
+Install Cilium, enable Hubble and deploy Hubble Relay and Hubble's graphical UI
+in one command using Helm:
 
 .. parsed-literal::
 
@@ -58,18 +48,6 @@ Install Cilium release via Helm:
       --set global.hubble.relay.enabled=true \\
       --set global.hubble.ui.enabled=true
 
-.. tip::
-   If your local network subnet conflicts with the one picked up by kind,
-   update the ``networking`` section of the kind configuration file to specify
-   different subnets (pick a network range that does not conflict with yours)
-   and re-create the cluster.
-
-   .. parsed-literal::
-        networking:
-          disableDefaultCNI: true
-          podSubnet: "10.244.0.0/16"
-          serviceSubnet: "10.245.0.0/16"
-
 Validate the Installation
 =========================
 
@@ -192,17 +170,16 @@ port-forward the Hubble Relay service locally:
    This terminal window needs to be remain open to keep port-forwarding in
    place. Open a separate terminal window to use the ``hubble`` CLI.
 
-You may test that your setup is working by issuing this command which gives you
-the status of the Hubble Relay service:
+Confirm that the Hubble Relay service is healthy via ``hubble status``:
 
 .. parsed-literal::
    $ hubble status --server localhost:4245
    Healthcheck (via localhost:4245): Ok
    Max Flows: 16384
 
 
-In order to avoid passing ``--server localhost:4245`` to ever command below,
-you may export the following environment variable:
+In order to avoid passing ``--server localhost:4245`` to every command, you may
+export the following environment variable:
 
 .. parsed-literal::
    $ export HUBBLE_DEFAULT_SOCKET_PATH=localhost:4245

Documentation/gettingstarted/kind-install.rst

@@ -13,36 +13,66 @@ Install Dependencies
 4. Install ``kind`` >= v0.7.0 per kind documentation:
    `Installation and Usage <https://kind.sigs.k8s.io/#installation-and-usage>`_
 
-Kind Configuration
-==================
+Configure kind
+==============
 
-Kind does not use flags for configuration. Instead, it uses YAML configuration
-that is very similar to Kubernetes.
+Configuring kind cluster creation is done using a YAML configuration file.
+This step is necessary in order to disable the default CNI and replace it with
+Cilium.
 
 Create a :download:`kind-config.yaml <./kind-config.yaml>` file based on the
-following template. The template will create 3 nodes + 1 apiserver cluster with
-the latest version of Kubernetes from when the kind release was created.
+following template. It will create a cluster with 3 worker nodes and 1
+control-plane node.
 
 .. literalinclude:: kind-config.yaml
    :language: yaml
 
+By default, the latest version of Kubernetes from when the kind release was
+created is used.
+
 To change the version of Kubernetes being run,  ``image`` has to be defined for
 each node. See the
-`Node Configration <https://kind.sigs.k8s.io/docs/user/configuration/#nodes>`_
-documentation.
+`Node Configuration <https://kind.sigs.k8s.io/docs/user/configuration/#nodes>`_
+documentation for more information.
+
+.. tip::
+    By default, kind uses the following pod and service subnets:
+
+    .. parsed-literal::
+        Networking.PodSubnet     = "10.244.0.0/16"
+        Networking.ServiceSubnet = "10.96.0.0/12"
+
+    If any of these subnets conflicts with your local network address range,
+    update the ``networking`` section of the kind configuration file to specify
+    different subnets that do not conflict or you risk having connectivity
+    issues when deploying Cilium. For example:
 
-Start Kind
-==========
+    .. code-block:: yaml
 
-Pass the ``kind-config.yaml`` you created with the ``--config`` flag of kind.
+         networking:
+           disableDefaultCNI: true
+           podSubnet: "10.10.0.0/16"
+           serviceSubnet: "10.11.0.0/16"
+
+Create a cluster
+================
+
+To create a cluster with the configuration defined above, pass the
+``kind-config.yaml`` you created with the ``--config`` flag of kind.
 
 .. code:: bash
 
     kind create cluster --config=kind-config.yaml
 
-This will add a ``kind-kind`` context to ``KUBECONFIG`` or if unset,
-``${HOME}/.kube/config``
+After a couple of seconds or minutes, a 4 nodes cluster should be created.
+
+A new ``kubectl`` context (``kind-kind``) should be added to ``KUBECONFIG`` or, if unset,
+to ``${HOME}/.kube/config``:
 
 .. code:: bash
 
     kubectl cluster-info --context kind-kind
+
+.. note::
+   The cluster nodes will remain in state ``NotReady`` until Cilium is deployed.
+   This behavior is expected.

Documentation/gettingstarted/kind-preload.rst

@@ -0,0 +1,6 @@
+Preload the ``cilium`` image into each worker node in the kind cluster:
+
+.. parsed-literal::
+
+  docker pull cilium/cilium:|IMAGE_TAG|
+  kind load docker-image cilium/cilium:|IMAGE_TAG|

Documentation/gettingstarted/kind.rst

@@ -11,9 +11,8 @@ Getting Started Using Kind
 **************************
 
 This guide uses `kind <https://kind.sigs.k8s.io/>`_ to demonstrate deployment
-and operation of Cilium in a multi-node Kubernetes cluster.
-
-Kind requires docker to be installed and running.
+and operation of Cilium in a multi-node Kubernetes cluster running locally on
+Docker.
 
 .. include:: kind-install.rst
 
@@ -23,17 +22,9 @@ Install Cilium
 ==============
 
 .. include:: k8s-install-download-release.rst
+.. include:: kind-preload.rst
 
-
-**(optional, but recommended)** Pre-load Cilium images into the kind cluster so
-each worker doesn't have to pull them.
-
-.. parsed-literal::
-
-  docker pull cilium/cilium:|IMAGE_TAG|
-  kind load docker-image cilium/cilium:|IMAGE_TAG|
-
-Install Cilium release via Helm:
+Then, install Cilium release via Helm:
 
 .. parsed-literal::
 
@@ -48,18 +39,6 @@ Install Cilium release via Helm:
       --set global.pullPolicy=IfNotPresent \\
       --set config.ipam=kubernetes
 
-.. tip::
-   If your local network subnet conflicts with the one picked up by kind,
-   update the ``networking`` section of the kind configuration file to specify
-   different subnets (pick a network range that does not conflict with yours)
-   and re-create the cluster.
-
-   .. parsed-literal::
-        networking:
-          disableDefaultCNI: true
-          podSubnet: "10.244.0.0/16"
-          serviceSubnet: "10.245.0.0/16"
-
 .. include:: k8s-install-validate.rst
 .. include:: namespace-kube-system.rst
 .. include:: hubble-enable.rst

Documentation/spelling_wordlist.txt

@@ -123,6 +123,7 @@ Polytechnique
 Portmap
 Pre
 Prefilter
+Preload
 Profiler
 Proxylib
 QCon