Danny Fowler dannykansas

The problem

There's enough trouble with puppet's ssl model (mandatory client certs) that people go and do odd things to get around it. The primary problem is that for lab/preproduction environments, if you reinstall machines frequently, you lose access to the private key that generated the original cert but (absent some puppet cert --clean [node] operation) the cert still exists, leading to the dreaded Retrieved certificate doesn't match private key error.

A solution

Generate a single client certificate which all your nodes use, and have the master determine node names from facter rather than the SSL DN. This way you can re-install nodes with impunity and as long as your bootstrap plops down the correct config and the cert+key, you don't have any more SSL issues.

The caveats

If you have autosign turned on, this change represents a shift in security tradeoffs: you can turn off autosign and therefore more tightly control which clients can talk to your server because they need to have your clie

Whether you're trying to give back to the open source community or collaborating on your own projects, knowing how to properly fork and generate pull requests is essential. Unfortunately, it's quite easy to make mistakes or not know what you should do when you're initially learning the process. I know that I certainly had considerable initial trouble with it, and I found a lot of the information on GitHub and around the internet to be rather piecemeal and incomplete - part of the process described here, another there, common hangups in a different place, and so on.

In an attempt to coallate this information for myself and others, this short tutorial is what I've found to be fairly standard procedure for creating a fork, doing your work, issuing a pull request, and merging that pull request back into the original project.

Creating a Fork

Just head over to the GitHub page and click the "Fork" button. It's just that simple. Once you've done that, you can use your favorite git client to clone your repo or j

mdadm

Glossary:

md: multiple devices

command	description
`cat /proc/mdstat`	show status of all raids
`mdadm --detail /dev/md0`	detailed status of raid md0

AWS CLI Cheatsheet

http://docs.aws.amazon.com/IAM/latest/UserGuide/best-practices.html https://www.youtube.com/watch?v=_wiGpBQGCjU

	# Start by checking if they fixed it upstream:

	brew update
	brew upgrade reattach-to-user-namespace

	# If it says it's already installed, they haven't fixed it upstream. So do this:

	# Edit the recipe:
	brew edit reattach-to-user-namespace

	var attempts = 1;

	function createWebSocket () {
	var connection = new WebSocket();

	connection.onopen = function () {
	// reset the tries back to 1 since we have a new connection opened.
	attempts = 1;

	// ...Your app's logic...

	git clean -xfd
	git submodule foreach --recursive git clean -xfd
	git reset --hard
	git submodule foreach --recursive git reset --hard
	git submodule update --init --recursive

	#/etc/puppet/environments/production/manifests/java01.pp
	node 'java01.example.lan' inherits default {
	file { '/etc/httpd/ssl':
	ensure => 'directory',
	owner => 'root',
	group => 'root',
	mode => '0640',
	recurse => 'remote',
	source => 'puppet:///files/ssl/example.com',
	}

	# Get IAM Role name from Instance Profile Id
	curl http://169.254.169.254/latest/meta-data/iam/info

	# Get credentials
	curl http://169.254.169.254/latest/meta-data/iam/security-credentials/<role-name>

	# More info
	http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html

	#!/bin/bash

	# Outputs a pipeline that targets agents that have the same 'name' meta-data
	# value as the step that does the pipeline upload. This means that all the
	# steps will run on the same agent machine, assuming that the 'name' meta-data
	# value is unique to each agent.
	#
	# Each agent needs to be configured with meta-data like so:
	#
	# meta-data="name=<unique-name>"