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How to connect to Azure AKS Kubernetes worker node by SSH

Nodes are not assigned public IP. If you have accessible VM in the same VNET as worker nodes, then you can use that VM as jump host and connect the worker via private IP.

Alternatively public IP can be assigned to a worker node. This readme shows how to do that.

Steps how to attach public IP to a worker node

find out the resource group that AKS created for the node VMs

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apiVersion: apps/v1
kind: Deployment
metadata:
  name: echoserver
spec:
  selector:
    matchLabels:
      app: echoserver
  template:
    metadata:

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Running Kind cluster

Preconditions

Install docker using install instructions at https://docs.docker.com/engine/install/ubuntu/:

$ sudo apt-get install -y \
    ca-certificates \
    curl \

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/*

## Compile

g++ -Wall -std=c++11 -rdynamic -g stack-backtrace.cpp -lbacktrace -o stack-backtrace &&  ./stack-backtrace
clang++ -Wall -std=c++11 -rdynamic -g stack-backtrace.cpp -lbacktrace -o stack-backtrace && ./stack-backtrace

## Output

  Backtrace:

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*** RSA

# Generate self-signed certificate with RSA 4096 key-pair
openssl req -x509 -nodes -days 3650 -newkey rsa:4096 -keyout rsakey.pem -out rsacert.pem

# print private and public key
openssl rsa -in rsakey.pem -text -noout

# print certificate
openssl x509 -in rsacert.pem -text -noout

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Step-by-step development tutorial: making a code change to Contour and seeing live results

This tutorial is a step-by-step guide to making a small code change to Contour. It shows how to run Contour locally on your laptop and have it control Envoy(s) running in a Kind cluster. It allows for a very fast feedback cycle and easy debugging.

Preparation

Create a Kind cluster, for example by running:

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Manual test procedure for slow start mode

This document describes manual test procedure for PR projectcontour/contour#4772

The test is executed by using k6. Additionally, it uses InfluxDB to record the performance test results and Grafana to visualize them.

Preparations

Spin up influxdb and grafana using docker-compose:

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#!/bin/env python3
#
# This script can be used as a server when you need to test the handling of
# TCP connection establishment timeouts of your client.
#
# The protocol can be HTTP, HTTPS or just about anything else, since connection
# will never be established.  It will hang in TCP handshake.
#

import socket

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How to use debug containers

Following K8s feature-gate must be enabled in kind (kubeadm) config file to access the feature

featureGates:
  EphemeralContainers: true

First we start debug / emphemeral container and attach it to contour shutdown-manager container.

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#!/usr/bin/env python3
#
# Extract TLS pre-master secret to decrypt captured TLS stream in Wireshark
#
# Java TLS implementation can be configured to dump information on TLS stream,
# making it possible to extracting TLS key for decrypting the stream for debug
# purposes.
#
# This script is originally by Timothy Basanov
#   https://timothybasanov.com/2016/05/26/java-pre-master-secret.html