Ketzacoatl ketzacoatl

Overview

This gist demonstrates how to run a docker container with nomad, using a wrapper script.

Why would you want to use this?

With the wrapper, we can more easily run the container in the way we need to and without being limited by Nomad's docker driver. For example, while Nomad will have great support for volumes in the future, it has no such support right now, and the driver does not expose a config parameter to tune the volumes mounted in the docker container. This is also a great way to use consul to lookup services before starting your app, or to retrieve credentials from Vault. When running legacy applications with nomad, the wrapper script is the place to put that type of look-up logic.

We use a wrapper script and the raw_exec driver to run the container with the parameters we need.

Useful Snippets for a few Random Ops Tasks

What..

This is a minimal reproduction of an issue I am seeing when provisioning hosts with Saltstack and Packer. More specifically, running salt-call --local saltutil.sync_all in a script uploaded by packer does not function as expected (no files/modules are sync'd).

Note that saltutil.sync_all works fine on the new host when run manually from the shell directly.

How to use..

Download and install packer to your $PATH from https://www.packer.io/downloads.html

Keybase proof

I hereby claim:

I am ketzacoatl on github.
I am ketzacoatl (https://keybase.io/ketzacoatl) on keybase.
I have a public key ASABHBuq9eKf_Tg1I5nNIxbqYyoqLkQixEdaZ1v_cOSNcAo

To claim this, I am signing this object:

This is the common component:

# Create a single load balancer for all Atlassian services
resource "aws_alb" "atlassian" {
  name            = "${var.name}"
  internal        = false
  idle_timeout    = "300"
  security_groups = [ 
 "${aws_security_group.atlassian-alb.id}",

	{%- set repo_root = '/root/consul-template' %}
	{%- set revision = 'v0.10.0' %}

	include:
	- golang


	consul-template:
	git.latest:
	- name: https://github.com/hashicorp/consul-template

	import sys
	from time import sleep

	import consul
	import consul_lock
	from docker import Client

	'''
	This is a PoC which uses consul's locking mechanism to ensure only
	one instance of the named docker container is running. Requires:

	{-# LANGUAGE RecordWildCards #-}
	{-# LANGUAGE OverloadedStrings #-}

	module Main where

	import Network.Consul (getSelf, ConsulClient(..), initializeConsulClient, listKeys)
	import qualified Network.Consul.Internal as I

	client = initializeConsulClient "localhost" 8500 Nothing

	2016/11/19 09:49:12 [INFO] Terraform version: 0.8.0 dev 283d49f12fe203a2cd2ad23acec046f72f7842de+CHANGES
	2016/11/19 09:49:12 [INFO] CLI args: []string{"/home/user/bin/terraform-v0.8.0-dev", "apply"}
	2016/11/19 09:49:12 [DEBUG] Detected home directory from env var: /home/user
	2016/11/19 09:49:12 [DEBUG] Detected home directory from env var: /home/user
	2016/11/19 09:49:12 [DEBUG] Attempting to open CLI config file: /home/user/.terraformrc
	2016/11/19 09:49:12 [DEBUG] File doesn't exist, but doesn't need to. Ignoring.
	2016/11/19 09:49:12 [DEBUG] Detected home directory from env var: /home/user
	2016/11/19 09:49:12 [TRACE] Preserving existing state lineage "a56754c9-aed5-4dce-92f8-921e3c1de105"
	2016/11/19 09:49:12 [TRACE] Preserving existing state lineage "a56754c9-aed5-4dce-92f8-921e3c1de105"
	2016/11/19 09:49:12 [TRACE] Graph after step *terraform.ConfigTransformerOld:

	apiVersion: v1
	kind: ConfigMap
	metadata:
	name: prometheus
	namespace: ops
	data:
	prometheus.yml: \|
	global:
	scrape_interval: 30s
	scrape_timeout: 30s