Troy Fontaine troyfontaine

MySQL RDS Cheat Sheet

1. Install the Command Line Client

On Ubuntu

sudo apt-get install mysql-client

2. Use the command-line client to connect

The below command will connect to the rds server specified after -h and open a MySQL client connection that you can run commands against.

Troubleshooting HAProxy

Step 1: Verify that HAProxy is running

On ubuntu, run the following command:

sudo service haproxy status

You should see output like below if it is running:

haproxy is running.

Troubleshooting Ethernet on Ubuntu

Here are some commands to help troubleshoot network card issues on Ubuntu:

Find Connection State

Determine Speed and Duplex

dmesg |grep eth0

Steps to join an Ubuntu 14.04 Server to Active Directory using realmd

Step 1: Perform updates

apt-get update

Step 2: Install realmd

apt-get install -y realmd

Google Authenticator for SSH How-To

Installing the Google Authenticator pam package alone does not configure a system for 2 Factor Authentication when connecting via SSH.

Overview

The Google Authenticator package can be installed on Ubuntu via apt-get on Ubuntu 14.04.3 and later (that I've confirmed).

It provides a pam module that allows you to prompt a user for a code generated via a Google Authenticator app or other compatible TOTP app (such as 1Password). The script below enables the authenticator prompt when using ssh and password authentication.

A few things to keep in mind:

You cannot enable Google Authenticator for Public Key-based authentication at the same time as Password-based authentication

	# !/bin/bash
	# Script to use Fleetctl to stop and start containers using a rolling restart
	# By Troy Fontaine with rolling restart script from http://engineering.rainchasers.com/coreos/fleet/2015/03/03/rolling-unit-restart.html

	# Grab list of containers and assign to array
	container_list=($(fleetctl list-units -fields=unit -no-legend \| cut -f2 ))

	# Prepare variable for later use
	container=""

	#!/bin/bash

	# Install pre-requisites
	apt-get install software-properties-common

	# Add PPAs
	apt-add-repository ppa:brightbox/ruby-ng -y
	apt-add-repository ppa:ansible/ansible -y

	# Run update

	<domain type='kvm'>
	<name>MyServer</name>
	<memory unit='KiB'>4194304</memory>
	<currentMemory unit='KiB'>4194304</currentMemory>
	<vcpu placement='static'>4</vcpu>
	<os>
	<type arch='x86_64' machine='pc-i440fx-wily'>hvm</type>
	<boot dev='hd'/>
	</os>
	<features>

	Content-Type: multipart/mixed; boundary="===============0035287898381899620=="
	MIME-Version: 1.0

	--===============0035287898381899620==
	Content-Type: text/cloud-config; charset="us-ascii"
	MIME-Version: 1.0
	Content-Transfer-Encoding: 7bit
	Content-Disposition: attachment; filename="cloud-config.txt"
	#cloud-config