docs: More detail on whats needed to support pods on Windows nodes (#…

…3894)

* docs: More detail on whats needed to support pods on Windows nodes

* Added recommendations and configuration for collection on clusters with windows nodes

docs/windows.md

@@ -5,11 +5,65 @@ support for windows.
 
 ## Running collection on windows nodes
 
-In order to fully support windows nodes, the following issues should be addressed:
+- To setup a k8s cluster with windows nodes, here's a terraform registry for reference:
 
-- Windows nodes do not support linux filesystems
-- We should use HostProcess Containers to support log collection
-- Lack of windows supported containers
+  - https://registry.terraform.io/modules/aws-samples/windows-workloads-on-aws/aws/latest/submodules/eks-windows
+
+- It is a known limitation that windows nodes only support the containerd runtime:
+
+  - https://kubernetes.io/docs/concepts/windows/intro/#containerd
+
+- We need the Windows nodes to use containerd 1.7.1 or greater to keep linux mounts on Windows hosts
+
+  - https://kubernetes.io/docs/tasks/configure-pod-container/create-hostprocess-pod/#containerd-v1-7-and-greater
+  - PR: https://github.com/containerd/containerd/pull/8331
+
+- The logs collection container (and possibly others) must be HostProcess containers for privileged access on the Windows node
+
+  - https://kubernetes.io/docs/tasks/configure-pod-container/create-hostprocess-pod/#hostprocess-pod-configuration-requirements
+
+- The metadata enrichment layer continues to run on linux nodes
+
+- Only pods responsible for collecting logs, run on both windows and linux nodes
+
+- The windows container base images we use are mentioned below
+
+  - https://hub.docker.com/r/microsoft/windows-nanoserver
+
+- Hardware recommendations for Windows containers
+  - https://kubernetes.io/docs/concepts/windows/intro/#windows-hardware-recommendations
+
+## Recommendations and limitations
+
+Kubernetes clusters are required to have linux nodes even in clusters predominantly running windows nodes. This is because the k8s control
+plane requires linux nodes. Based on this, we recommend the following:
+
+- It is currently recommended to have atleast 3 linux nodes for the control plane and the opentelemetry metadata enrichment layer
+- Logs collection on windows nodes is currently experimental. Only container logs are currently ingested.
+- Metrics and traces collection is only supported on linux nodes
+
+## Configuration
+
+- To enable logs collection on Windows nodes please use the configuration below
+
+  ```
+  sumologic:
+    logs:
+      collector:
+        otellogswindows:
+          enabled: true
+  ```
+
+- To change the base image for windows containers please see the example below:
+
+  ```
+  sumologic:
+    clusterName: k8s-cluster
+  otellogswindows:
+  image:
+    repository: "public.ecr.aws/sumologic/sumologic-otel-collector-dev"
+    tag: "latest-windows-amd64-ltsc2022"
+  ```
 
 ### Known Issues