James Sturtevant jsturtevant

CNI SNIFFER

The Container Networking Interface, or CNI, is a generic plugin-based networking solution for configuring the network on containers.

The CNI specification defines:

A format for administrators to define network configuration.
A protocol for container runtimes to make requests to network plugins.
A procedure for executing plugins based on a supplied configuration.
A procedure for plugins to delegate functionality to other plugins.

Video

This content was presented at a sig-testing meeting on 8/25/2020, available as a video here

Links / References

ctr -n k8s.io image list

difference between hyperv and isolated

[plugins.cri.containerd.runtimes.runhcs-wcow-hypervisor]
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runhcs-wcow-process]

https://github.com/Azure/aks-engine/compare/master...marosset:hyper-v https://github.com/Azure/aks-engine/blob/master/parts/k8s/windowscontainerdfunc.ps1

https://k8swin.blob.core.windows.net/k8s-windows/aks-engine-ce5c82940-marosset-hyperv.tar.gz

Using Prometheus and Grafana to Monitor Kubernetes Clusters and NGINX Metrics

You can create your own Grafana dashboard from scratch, but this guide will show you how to import an already existing Grafana dashboard that contains most of the Kubernetes and NGINX metrics you would want to monitor.

Prerequisites

Kubernetes cluster
Helm 3

Note: If you need to migrate from Helm 2 to Helm 3, I recommend using this plugin.

Observation

Approximately 10% increase in CPU usage when running containerized application vs running the application directly on the host

Troubleshooting

Tools & Setup:

Windows Performance Recorder: built-in tool to troubleshoot performance related issues on Windows.

Alerts with Prometheus

The helm installation makes it particularly simple to get going: https://github.com/kubernetes/charts/tree/master/stable/prometheus.

Now you just have to worry about

Creating the alert
Creating the alert rules

Creating the alert

What kind of alert do you want and where do you want it to go? This is defined in the configMap for alertManager, which can be found in the alertmanagerFiles.alertmanager.yml portion of the values.yaml file of the helm chart.

	# Copyright: (c) 2022, Jordan Borean (@jborean93) <[email protected]>
	# MIT License (see LICENSE or https://opensource.org/licenses/MIT)

	Function Trace-TlsHandshake {
	<#
	.SYNOPSIS
	TLS Handshake Diagnostics.

	.DESCRIPTION
	Performs a TLS handshake and returns diagnostic information about that

	#!/bin/sh
	#https://itnext.io/get-a-shell-to-a-kubernetes-node-9b720a15a4fe
	set -x
	node=${1}
	nodeName=$(kubectl get node ${node} -o template --template='{{index .metadata.labels "kubernetes.io/hostname"}}')
	nodeSelector='"nodeSelector": { "kubernetes.io/hostname": "'${nodeName:?}'" },'
	podName=${USER}-nsenter-${node}
	kubectl run ${podName:?} --restart=Never -it --rm --image overriden --overrides '
	{
	"spec": {

	{
	"Name": "Azure k8s Cloud Provider",
	"IsCustom": true,
	"Description": "Everything needed by the k8s 1.11 Azure cloud provider (not including ACR, addons, etc)",
	"Actions": [
	"Microsoft.Compute/disks/delete",
	"Microsoft.Compute/disks/read",
	"Microsoft.Compute/disks/write",
	"Microsoft.Compute/virtualMachineScaleSets/manualUpgrade/action",
	"Microsoft.Compute/virtualMachineScaleSets/read",

	http://localhost:8001/api/v1/nodes/2618k8s000/proxy/stats/summary
	https://github.com/kubernetes/kubernetes/blob/1f70708f6cc85985725c11cd69c4965c1f97b314/pkg/kubelet/server/server.go#L17
	http://localhost:8001/api/v1/nodes/win-p-win000000/proxy/logs/kubelet/