extra env var and ha updates

content/rke/v0.1.x/en/config-options/_index.md

@@ -21,8 +21,8 @@ There are several options that can be configured in cluster configuration option
 * [Kubernetes Version](#kubernetes-version)
 * [System Images]({{< baseurl >}}/rke/v0.1.x/en/config-options/system-images/)
 * [Services]({{< baseurl >}}/rke/v0.1.x/en/config-options/services/)
+* [Extra Args and Binds and Environment Variables]({{< baseurl >}}/rke/v0.1.x/en/config-options/services/services-extras/)
 * [External Etcd]({{< baseurl >}}/rke/v0.1.x/en/config-options/services/external-etcd/)
-* [Extra Args and Binds]({{< baseurl >}}/rke/v0.1.x/en/config-options/services/extra-args-and-binds/)
 * [Authentication]({{< baseurl >}}/rke/v0.1.x/en/config-options/authentication/)
 * [Authorization]({{< baseurl >}}/rke/v0.1.x/en/config-options/authorization/)
 * [Cloud Providers]({{< baseurl >}}/rke/v0.1.x/en/config-options/cloud-providers/)

content/rke/v0.1.x/en/config-options/services/services-extras/_index.md

@@ -1,12 +1,12 @@
 ---
-title: Extra Args and Binds
+title: Extra Args, Extra Binds, and Extra Environment Variables
 weight: 231
 draft: true
 ---
 
-RKE supports the ability to configure your Kubernetes components by adding in extra service arguments to these components.
+RKE supports additional service arguments, volume binds and environment variables.
 
-## Extra Args
+### Extra Args
 
 For any of the Kubernetes services, you can update the `extra_args` to change the existing defaults.
 
@@ -21,9 +21,9 @@ services:
         cluster-name: "mycluster"
 ```
 
-## Extra Binds
+### Extra Binds
 
-Additional volume binds can be made to services using the `extra_binds` arguments.
+Additional volume binds can be added to services using the `extra_binds` arguments.
 
 ```yaml
 services:
@@ -32,3 +32,14 @@ services:
         - "/host/dev:/dev"
         - "/usr/libexec/kubernetes/kubelet-plugins:/usr/libexec/kubernetes/kubelet-plugins:z"
 ```
+
+### Extra Environment Variables
+
+Additional environment variables can be added to services by using the `extra_env` arguments.
+
+```yaml
+services:
+    kubelet:
+      extra_env:
+        - "HTTP_PROXY=http://your_proxy"
+```

content/rke/v0.1.x/en/installation/_index.md

@@ -158,6 +158,12 @@ Instead of creating a file, you can print the generated configuration to stdout
 $ rke config --print
 ```
 
+### High Availability
+
+RKE is HA ready, you can specify more than one `controlplane` node in the `cluster.yml` file. RKE will deploy master components on all of these nodes and the kubelets are configured to connect to `127.0.0.1:6443` by default which is the address of `nginx-proxy` service that proxy requests to all master nodes.
+
+To create an HA cluster, specify more than one host with role `controlplane`. 
+
 ## Deploying Kubernetes with RKE
 
 After you've created your `cluster.yml`, you can deploy your cluster with a simple command. This command assumes the `cluster.yml` file is in the same directory as where you are running the command.

content/rke/v0.1.x/en/installation/upgrades/_index.md

@@ -40,7 +40,7 @@ First, RKE will use the local `kube_config_cluster.yml` to confirm the versions
 
 [Services]({{< baseurl >}}/rke/v0.1.x/en/config-options/services/) can be upgraded by changing any of the services arguments or `extra_args` and running `rke up` again with the updated configuration file.
 
-> **Note:** The following arguments, `service_cluster_ip_range` or `cluster_cidr`, cannot be changed as any changes to these arguments will result in a broken cluster. Currently, network pods will not be automatically upgraded.
+> **Note:** The following arguments, `service_cluster_ip_range` or `cluster_cidr`, cannot be changed as any changes to these arguments will result in a broken cluster. Currently, network pods are not automatically upgraded.
 
 ## Add-Ons Upgrades