Balla Roland broland07

#Unix Toolbox

This document is a collection of Unix/Linux/BSD commands and tasks which are useful for IT work or for advanced users. This is a practical guide with concise explanations, however the reader is supposed to know what s/he is doing.

##Unix Toolbox revision 14.4

The latest version of this document can be found at http://cb.vu/unixtoolbox.xhtml. Replace .xhtml on the link with .pdf for the PDF version and with .book.pdf for the booklet version. On a duplex printer the booklet will create a small book ready to bind. This XHTML page can be converted into a nice PDF document with a CSS3 compliant application (see the script example). See also the about page.
Error reports and comments are m

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

Clarify and agree on the scope of the system

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

Processing JSON using jq

jq is useful to slice, filter, map and transform structured json data.

Installing jq

On Mac OS

brew install jq

My Openshift Cheatsheet

Project Quotes, Limits and Templates

Cluster Quota

oc create clusterquota env-qa \
    --project-label-selector environment=qa \
    --hard pods=10,services=5
    
oc create clusterquota user-qa \

	#!/bin/bash

	# Install dependencies
	# older ubuntus
	#apt-get install build-essential libsqlite3-dev ruby1.9.1-dev
	# xenial
	apt install build-essential libsqlite3-dev ruby-dev

	# Install the gem
	gem install mailcatcher --no-ri --no-rdoc

	#!/bin/sh
	echo "Stopping firewall, clean all rules..."

	iptables -P INPUT ACCEPT
	iptables -P FORWARD ACCEPT
	iptables -P OUTPUT ACCEPT
	iptables -t nat -F
	iptables -t mangle -F
	iptables -F
	iptables -X

	# === Optimized my.cnf configuration for MySQL/MariaDB (on Ubuntu, CentOS, Almalinux etc. servers) ===
	#
	# by Fotis Evangelou, developer of Engintron (engintron.com)
	#
	# ~ Updated September 2024 ~
	#
	#
	# The settings provided below are a starting point for a 8-16 GB RAM server with 4-8 CPU cores.
	# If you have different resources available you should adjust accordingly to save CPU, RAM & disk I/O usage.
	#

	# Backup
	docker exec CONTAINER /usr/bin/mysqldump -u root --password=root DATABASE > backup.sql

	# Restore
	cat backup.sql \| docker exec -i CONTAINER /usr/bin/mysql -u root --password=root DATABASE

	#! /usr/bin/env bash

	# Install any build dependencies needed for curl
	sudo apt-get build-dep curl

	# Get latest (as of Feb 25, 2016) libcurl
	mkdir ~/curl
	cd ~/curl
	wget http://curl.haxx.se/download/curl-7.50.2.tar.bz2
	tar -xvjf curl-7.50.2.tar.bz2

	# install haproxy
	yum install -y haproxy

	# config haproxy for rabbitmq
	cat > /etc/haproxy/haproxy.cfg << "EOF"
	global
	log 127.0.0.1 local0 notice

	maxconn 10000
	user haproxy