jbenet

a simple git branching model (written in 2013)

This is a very simple git workflow. It (and variants) is in use by many people. I settled on it after using it very effectively at Athena. GitHub does something similar; Zach Holman mentioned it in this talk.

Update: Woah, thanks for all the attention. Didn't expect this simple rant to get popular.

philfreo

#!/usr/bin/env python

import time
import boto
import boto.ec2.elb
import boto.utils

from flask.ext.script import Manager

from closeio.main import setup_app

dysinger

#!/bin/sh
# linux firewall/forwarding
modprobe iptable_nat
echo 1 | tee /proc/sys/net/ipv4/ip_forward
iptables -t nat -A POSTROUTING -s 10.10.10.1/2 -o eth0 -j MASQUERADE
# install openvpn
apt-get update && apt-get install -y openvpn
cd /etc/openvpn/
INSTANCE=$(curl http://169.254.169.254/latest/meta-data/public-hostname)
openvpn --genkey --secret ${INSTANCE}.key

joemiller

#!/usr/bin/env ruby
#
# check-rackspace-bandwidth-limits
# ================================
#
# Check the bandwidth usage of a network device on a Rackspace Cloud server
# and alert if it is nearing the threshold allowed for the image size.
#
# Requires sar(1) and sadf(1) to be installed (sysstat package, usually)
#

fujin

ubuntu@continubus:~/dockerfiles/go-agent$ docker ps
ID                  IMAGE                    COMMAND                CREATED              STATUS              PORTS
d89f44c4df5b        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
a132f54a0442        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
da8b513fbb2a        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
c100df11f9d7        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
929adf4cbc3b        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
79720ed86e0b        fujin/go-agent:latest    /bin/sh -c /start.sh   About a minute ago   Up About a minute                            
ca9403fe93e2        fujin/go-agent:latest    /b

jedi4ever

Clustering: The basics

The trick? pass the file descriptor from a parent process and have the server.listen reuse that descriptor. So multiprocess in their own memory space (but with ENV shared usually)

It does not balance, it leaves it to the kernel.

In the last nodejs > 0.8 there is a cluster module (functional although marked experimental)

• http://nodejs.org/api/cluster.html
• Simple cluster example:

ranjib

Chef 11 introduces event dispatching mechanism, which emits event at different milestones in Chef run (aka lifecycle) , and users can add their custom handlers to hook into these events. Chef formatters already uses this API. For a complete list of currently available events check this

Following is a bare minimal example for adding a custom handler:

chef_event_handler_foo.rb

require 'chef/event_dispatch/base'
class Foo < Chef::EventDispatch::Base
  # lets say hello world when chef run ends
 def run_completed(node)

joemiller

#!/usr/bin/env ruby
#
# this is a special meta-check. It runs ping checks against all hosts in
# the /endpoints API and sends individual results directly to sensu-client via
# the udp/3030 client socket. this is different from the normal sensu check model
# where individual scripts run and their exit status and output is used to create
# a single event.
#
# the reason for this check is to be able to dynamically ping a list of hosts
# without the race conditions and timing issues involved with creating individual

ranjib

Grab the validation client in json format from old chef server

knife client show chef-validator -c knife-chef-server-10.rb -Fj > chef-validator.json

Upload the validation client to new chef server, delete the existing validation client from new chef server first, as update(PUT) is not allowed, only create(POST) is allowed

knife client delete chef-validator -y -c knife-chef-server-11.rb

ranjib

require 'chef'
Chef::Config.from_file('knife.rb')
envs = Chef::Environment.list.keys
q = Chef::Search::Query.new
envs.each do |e|
  constrained_cookbooks = Chef::Environment.load(e).cookbook_versions.keys
  all_cookbooks =[]
  nodes = q.search(:node, "chef_environment:#{e}").first.reject(&:nil?)
  nodes.select{|n| n.attribute?(:recipes)}.each do |n|
    n.recipes.map{|r| r.split('::')[0]}.each do |cookbook|