Thomas Hikade thikade

This was initially posted in an kubernetes-sigs/kustomize issue.

We are using Kustomize's vars feature. Initially we didn't understand how to use it for our purpose, but it is a 100% fit. One example is our Ingress resource, which looks like this:

# file: base/ingress.yaml
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  name: services

Change apiVersion from:
```
- apiVersion: v1
```
(or apiVersion: apps.openshift.io/v1)

to:

Create a backend service that simply serves the pod name, and a frontend haproxy instance that balances based on client cookies.

# This is the backend service
apiVersion: v1
kind: Service
metadata:
  name: hostname
  annotations:
    # Enable sticky-ness on "SERVERID"
    serviceloadbalancer/lb.cookie-sticky-session: "true"

Don't use VPN services.

No, seriously, don't. You're probably reading this because you've asked what VPN service to use, and this is the answer.

Note: The content in this post does not apply to using VPN for their intended purpose; that is, as a virtual private (internal) network. It only applies to using it as a glorified proxy, which is what every third-party "VPN provider" does.

A Russian translation of this article can be found here, contributed by Timur Demin.
A Turkish translation can be found here, contributed by agyild.
There's also this article about VPN services, which is honestly better written (and has more cat pictures!) than my article.

Squashing Git Commits

The easy and flexible way

This method avoids merge conflicts if you have periodically pulled master into your branch. It also gives you the opportunity to squash into more than 1 commit, or to re-arrange your code into completely different commits (e.g. if you ended up working on three different features but the commits were not consecutive).

Note: You cannot use this method if you intend to open a pull request to merge your feature branch. This method requires committing directly to master.

Switch to the master branch and make sure you are up to date:

Linux NetFilter, IP Tables and Conntrack Diagrams

IPTABLES TABLES and CHAINS

IPTables has the following 4 built-in tables.

1) Filter Table

Filter is default table for iptables. So, if you don’t define you own table, you’ll be using filter table. Iptables’s filter table has the following built-in chains.

	#!/bin/bash

	echo "Switching to Logging project"
	oc project openshift-logging
	echo
	echo

	# fetch one ELA pod to run queries against
	es_pod=$(oc get pod --selector=component=elasticsearch --no-headers -o jsonpath='{range .items[?(@.status.phase=="Running")]}{.metadata.name}{"\n"}{end}' \| head -n1)

	// Example showing how to patch Kubernetes resources.
	package main

	import (
	"encoding/json"
	"fmt"

	"k8s.io/apimachinery/pkg/runtime/schema"
	types "k8s.io/apimachinery/pkg/types"
	"k8s.io/client-go/dynamic"

	import jenkins.model.*

	def matchedJobs = Jenkins.instance.items.findAll { job ->
	job.name =~ /my_regex_here/
	}

	matchedJobs.each { job ->
	println job.name
	//job.delete()
	}

	#To Decrypt Jenkins Password from credentials.xml
	#<username>jenkins</username>
	#<passphrase>your-sercret-hash-S0SKVKUuFfUfrY3UhhUC3J</passphrase>


	#go to the jenkins url
	http://jenkins-host/script

	#In the console paste the script
	hashed_pw='your-sercret-hash-S0SKVKUuFfUfrY3UhhUC3J'