docs: [NPM] add windows documentation and update links to MSDocs (#1805)

* add windows and update doc links

* update main README to say NPM supports Windows

* update preview wording to be clearer

---------

Co-authored-by: Vamsi Kalapala <[email protected]>

Author: huntergregory

README.md

@@ -14,7 +14,7 @@ This repository contains container networking services and plugins for Linux and
 
 * [Azure CNI network and IPAM plugins](docs/cni.md) for Kubernetes.
 * [Azure CNM (libnetwork) network and IPAM plugins](docs/cnm.md) for Docker Engine. **(MAINTENANCE MODE)**
-* [Azure NPM - Kubernetes Network Policy Manager](docs/npm.md) (Supports only linux for now).
+* [Azure NPM - Kubernetes Network Policy Manager](docs/npm.md) (Linux and (preview) Windows Server 2022)
 
 The `azure-vnet` network plugins connect containers to your [Azure VNET](https://docs.microsoft.com/en-us/azure/virtual-network/virtual-networks-overview), to take advantage of Azure SDN capabilities. The `azure-vnet-ipam` IPAM plugins provide address management functionality for container IP addresses allocated from Azure VNET address space.
 

docs/npm.md

@@ -4,20 +4,29 @@
 
 `azure-npm` Network Policy plugin implements the [Kubernetes Network Policy](https://kubernetes.io/docs/concepts/services-networking/network-policies/)
 
-The plugin is available on Linux platform. Windows support is planned.
+The plugin is available on Linux and (preview) Windows Server 2022.
 
 Azure-NPM serves as a distributed firewall for the Kubernetes cluster, and it can be easily controlled by `kubectl`.
 
+## Documentation
+1. [Secure traffic between pods using network policies in Azure Kubernetes Service (AKS)](https://learn.microsoft.com/en-us/azure/aks/use-network-policies)
+2. [Monitor and Visualize Network Configurations with Azure NPM](https://learn.microsoft.com/en-us/azure/virtual-network/kubernetes-network-policies#monitor-and-visualize-network-configurations-with-azure-npm)
+
 ## Install
+Specify `--network-policy=azure` when creating an AKS cluster. For more information, see the [Microsoft Docs](https://learn.microsoft.com/en-us/azure/aks/use-network-policies#create-an-aks-cluster-and-enable-network-policy).
 
+### Manual Installation
 Running the command below will bring up one azure-npm instance on each Kubernetes node.
 ```
+# linux
 kubectl apply -f https://raw.githubusercontent.com/Azure/azure-container-networking/master/npm/deploy/npm/azure-npm.yaml
+# windows
+kubectl apply -f https://raw.githubusercontent.com/Azure/azure-container-networking/master/npm/examples/windows/azure-npm.yaml
 ```
 Now you can secure your Kubernetes cluster with Azure-NPM by applying Kubernetes network policies.
 
 ## Build
-
+### Linux
 `azure-npm` can be built directly from the source code in this repository.
 ```
 make azure-npm
@@ -29,16 +38,39 @@ The second command builds the `azure-npm` docker image.
 The third command builds the `azure-npm` binary and place it in a tar archive. 
 The binaries are placed in the `output` directory.
 
-## Usage
+### Windows
+```
+$env:ACN_PACKAGE_PATH = "github.com/Azure/azure-container-networking"
+$env:NPM_AI_PATH = "$env:ACN_PACKAGE_PATH/npm.aiMetadata"
+$env:NPM_AI_ID = "1234abcd-1234-abcd-1234-12345678abcd"
+$env:VERSION = "0.0.0"
+$env:REPO = "mcr.microsoft.com/azure-npm:" # include colon at end
+$env:IMAGE = "$env:REPO$env:VERSION"
+docker build `
+	-f npm/windows.Dockerfile `
+	-t $env:IMAGE `
+	--build-arg VERSION=$env:VERSION `
+	--build-arg NPM_AI_PATH=$env:NPM_AI_PATH `
+	--build-arg NPM_AI_ID=$env:NPM_AI_ID `
+	.
+docker push $env:IMAGE
+echo $env:IMAGE
+```
 
-Microsoft docs has a detailed step by step example on how to use Kubernetes network policy.
-1. [Deny all inbound traffic to a pod](https://docs.microsoft.com/en-us/azure/aks/use-network-policies#deny-all-inbound-traffic-to-a-pod)
-2. [Allow inbound traffic based on a pod label](https://docs.microsoft.com/en-us/azure/aks/use-network-policies#allow-inbound-traffic-based-on-a-pod-label)
-3. [Allow traffic only from within a defined namespace](https://docs.microsoft.com/en-us/azure/aks/use-network-policies#allow-traffic-only-from-within-a-defined-namespace)
+## Usage
+[Microsoft Docs](https://learn.microsoft.com/en-us/azure/aks/use-network-policies#verify-network-policy-setup) has a detailed step by step example on how to use Kubernetes network policy.
 
 ## Troubleshooting
-
-`azure-npm` translates Kubernetes network policies into a set of `iptables` rules under the hood.
 When `azure-npm` isn't working as expected, try to **delete all networkpolicies and apply them again**.
 Also, a good practice is to merge all network policies targeting the same set of pods/labels into one yaml file.
 This way, operators can keep the minimum number of network policies and makes it easier for operators to troubleshoot.
+
+### Linux
+NPM adds firewall rules via `iptables` and `ipset`. You can examine the configuration on a given node with:
+- `kubectl exec -it -n kube-system $npmPod -- iptables -vnL`
+- `kubectl exec -it -n kube-system $npmPod -- ipset -L`
+
+### Windows
+NPM adds firewall rules via HNS. You can examine the configuration on a given node with:
+- ACLs applied on Pod Endpoints: `kubectl exec -n kube-system $npmWinPod -- Get-HNSEndpoint`
+- SetPolicies are like ipsets: `(Get-HNSNetwork | ? Name -Like Azure).Policies`