Patrick Henriksson phenri00

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

##Working with ansible-vault

I've been using a lot of Ansible lately and while almost everything has been great, finding a clean way to implement ansible-vault wasn't immediately apparent.

What I decided on was the following: put your secret information into a vars file, reference that vars file from your task, and encrypt the whole vars file using ansible-vault encrypt.

Let's use an example: You're writing an Ansible role and want to encrypt the spoiler for the movie Aliens.

#MongoDB 3.2.x Replica Sets on AWS EC2 A MongoDB replica set provides a mechanism to allow for a reliable database services. The basic replica set consists of three servers, a primary, a secondary and an arbitrator. The primary and secondary both hold a copy of the data. The arbitrator is normally a low spec server which just monitors the other servers and help with the failover process. In production, there can be more than three servers.

To setup mongo as a replica set on Amazon Web Services EC2 you need to first setup a security group with ssh on port 22 and mongodb on port 27017. You then need to create three servers. Select Ubuntu 14.04 LTS x64 and a micro (or bigger depending on your database size, ideally you should have enough memory to match your database size) instance for the primary and secondary and a nano instance for the arbitrator.

##Adjust the File System on each Server The operating system by default will update the last access time on a file. In a high data throughput database application

	adb help // List all comands

	== Adb Server
	adb kill-server
	adb start-server

	== Adb Reboot
	adb reboot
	adb reboot recovery
	adb reboot-bootloader

	package main

	import (
	"bytes"
	"encoding/gob"
	"fmt"
	"net"
	// "time"
	)

	#!/bin/bash

	set -eu

	NAMESPACE=$1
	PVCNAME=$2
	TARGETZONE=$3
	DEPLOYMENTOBJ=$4
	PVNAME=$(oc -n $NAMESPACE get pvc $PVCNAME --template={{.spec.volumeName}})
	VOLUMEID=$(oc -n $NAMESPACE get pv $PVNAME --template={{.spec.awsElasticBlockStore.volumeID}} \| cut -d/ -f 4)