Merge pull request #32 from slack/requirements

Consolidate system and configuration requirements into one spot.

Author: Jason Hansen

src/installing-deis/quickstart.md

@@ -4,30 +4,18 @@ These steps will help you provision a Deis cluster.
 
 ## Check System Requirements
 
-Please refer to the [system requirements][] for resource considerations when choosing a machine size to run Deis.
+Please refer to the prerequisites and [system requirements][] for considerations when planning your Kubernetes environment.
 
 ## Choose a Provider
 
-Choose one of the following providers and deploy a new kubernetes cluster:
+Choose one of the following providers and deploy a new Kubernetes cluster:
 
 - [Amazon AWS](http://kubernetes.io/v1.1/docs/getting-started-guides/aws.html)
 - [Google Container Engine](https://cloud.google.com/container-engine/docs/before-you-begin)
 - [Vagrant](http://kubernetes.io/v1.1/docs/getting-started-guides/vagrant.html)
 
 Reference [this table](http://kubernetes.io/v1.1/docs/getting-started-guides/#table-of-solutions) in the official Kubernetes documentation for a more extensive (but still non-exhaustive) list of Kubernetes provisioning options supported by the project or the community.
 
-## Prerequisites
-Please make sure you enable the Daemon Sets api if you are installing a pre-1.2 version of kubernetes. As it is not turned on by default. You can learn more about how to do that [here](http://kubernetes.io/v1.1/docs/api.html#enabling-resources-in-the-extensions-group).
-
-For example, with a CoreOS kubernetes cluster you can edit the api server unit file and add the following line to the `ExecStart` stanza: `--runtime_config=extensions/v1beta1=true,extensions/v1beta1/daemonsets=true`.
-
-Restart your api server and check that the extensions api is enabled:
-
-```
-$ kubectl api-versions
-$ extensions/v1beta1
-```
-
 ## Install Deis Platform
 
 Now that you've finished provisioning a cluster, please [Install the Deis Platform][install deis].

src/installing-deis/system-requirements.md

@@ -1,4 +1,4 @@
-# System Requirements
+# Resource Requirements
 
 When deploying Deis, it's important to provision machines with adequate resources. Deis is a highly-available distributed system, which means that Deis components and your deployed applications will move around the cluster onto healthy hosts as hosts leave the cluster for various reasons (failures, reboots, autoscalers, etc.). Because of this, you should have ample spare resources on any machine in your cluster to withstand the additional load of running services for failed machines.
 
@@ -13,8 +13,33 @@ Note that these estimates are for Deis and Kubernetes only, and there should be
 
 Running smaller machines will likely result in increased system load and has been known to result in component failures and other problems.
 
-## Network
 
-Due to changes introduced in Docker 1.3.1 related to insecure Docker registries, the hosts running Deis must be able to communicate via a private network procured by kubernetes in the `10.0.0.0/8` private address space. This allows the docker daemon used by the controller to communicate with the registry. Ensure that your hosts have the following entries in their respective DOCKER_OPTS:
+# Kubernetes Requirements
 
-	EXTRA_DOCKER_OPTS="--insecure-registry 10.0.0.0/8"
+## Versions
+
+Deis workflow has been tested with the Kubernetes v1.1 release line. While Kubernetes 1.2 may work we haven't fully tested that release.
+
+## Daemon Sets
+
+The logging components require Kubernetes Daemon Sets API. Daemon Sets are not enabled by default in the v1.1 release line. To enable these extensions, follow the instructions found [here](http://kubernetes.io/v1.1/docs/api.html#enabling-resources-in-the-extensions-group). If you are running Kubernetes v1.2, Daemon Sets are enabled by default.
+
+Specific steps to enable API extensions may vary based on your Kubernetes configuration. For example, to update a CoreOS Kubernetes cluster, edit the API server unit file and add the following line to the `ExecStart` stanza: `--runtime_config=extensions/v1beta1=true,extensions/v1beta1/daemonsets=true`.
+
+Restart your API server and check that the extensions API is enabled by running:
+
+```
+$ kubectl api-versions
+extensions/v1beta1
+v1
+```
+
+# Docker Requirements
+
+## Docker Version
+
+Any Kubernetes 1.1 cluster should also use a Docker version < 1.10.0 so that `kubectl exec` and Deis database health checks work properly (Refs: [fsouza/go-dockerclient#455](https://github.com/fsouza/go-dockerclient/issues/455) and [kubernetes/kubernetes#19720](https://github.com/kubernetes/kubernetes/issues/19720)).
+
+## Docker Insecure Registry
+
+The on-cluster, Deis-managed Docker registry is not deployed with TLS by default. As such, all Kubernetes worker nodes must have their Docker daemons configured to use an insecure registry. The subnet should encompase any private networks used by your worker nodes including any overlay networks. Depending on your Kubernetes and Docker configuration, setting `EXTRA_DOCKER_OPTS="--insecure-registry=10.0.0.0/8"` may be sufficient.