Salty Vagrant

Provision Vagrant boxes using Saltstack.

Discussion and questions happen in #salt on Freenode IRC. ping akoumjian.

Introduction

Just like Chef or Puppet, Salt can be used as a provisioning tool. Salty Vagrant lets you use your salt state tree and a your minion config file to automatically build your dev environment the same way you use salt to deploy for other environments.

There are two different ways to use Salty Vagrant. The simplest way uses the salt minion in a masterless configuration. With this option you distribute your state tree along with your Vagrantfile and a dev minion config. The minion will bootstrap itself and apply all necessary states.

The second method lets you specify a remote salt master, which assures that the vagrant minion will always be able to fetch your most up to date state tree. If you use a salt master, you will either need to manually accept new vagrant minions on the master, or distribute preseeded keys along with your vagrant files.

Masterless (Quick Start)

1. Install Vagrant
2. Install Salty Vagrant (gem install vagrant-salt)
3. Get the Ubuntu 12.04 base box: vagrant box add precise64 http://files.vagrantup.com/precise64.box
4. Create/Update your Vagrantfile (Detailed in Configuration)
5. Place your salt state tree in salt/roots/salt
6. Place your minion config in salt/minion [1]
7. Run vagrant up and you should be good to go.

[1]	Make sure your minion config sets file_client: local for masterless

Using Remote Salt Master

If you are already using Salt for deployment, you can use your existing master to provision your vagrant boxes as well. You will need to do one of the following:

1. Manually accept the vagrant's minion key after it boots. [2]
2. Preseed the Vagrant box with minion keys pre-generated on the master

[2]	This is not recommended. If your developers need to destroy and rebuild their VM, you will have to repeat the process.

Preseeding Vagrant Minion Keys

On the master, create the keypair and add the public key to the accepted minions folder:

root@saltmaster# salt-key --gen-keys=[minion_id]
root@saltmaster# cp minion_id.pub /etc/salt/pki/minions/[minion_id]

Replace [minion_id] with the id you would like to assign the minion.

Next you want to bundle the key pair along with your Vagrantfile, the salt_provisioner.rb, and your minion config. The directory should look something like this:

myvagrant/
    Vagrantfile
    salt/
        minion.conf
        key/
            minion.pem
            minion.pub

You will need to determine your own secure method of transferring this package. Leaking the minion's private key poses a security risk to your salt network.

The are two required settings for your minion.conf file:

master: [master_fqdn]
id: [minion_id]

Make sure you use the same [minion_id] that you used on the master or it will not match with the key.

Create/Update your Vagrantfile per the example provided in the Configuration section.

Finally, you should be able to run vagrant up and the salt should put your vagrant minion in state.highstate.

Configuration

Your Vagrantfile should look roughly like this:

Vagrant::Config.run do |config|
  config.vm.box = "precise64"
  ## Use all the defaults:
  config.vm.provision :salt do |salt|
    salt.run_highstate = true

    ## Optional Settings:
    # salt.minion_config = "salt/minion.conf"

    ## Only Use these with a masterless setup to
    ## load your state tree:
    # salt.salt_file_root_path = "salt/roots/salt"
    # salt.salt_pillar_root_path = "salt/roots/pillar"

    ## If you have a remote master setup, you can add
    ## your preseeded minion key
    # salt.master = true
    # salt.minion_key = "salt/key/testing.pem"
    # salt.minion_pub = "salt/key/testing.pub"
  end
end

Inside of your Vagrantfile, there are a few parameters you can assign depending on whether you are running masterless or with a remote master.

minion_config : "salt/minion.conf"

Path to your minion configuration file.

minion_key : false

String path to your minion key. Only useful with master=true

minion_pub : false

String path to your minion public key. Only useful with master=true

master : false

Boolean whether or not you want to use a remote master. If set to false, make sure your minion config file has file_client: local set.

salt_file_root_path : "salt/roots/salt"

String path to your salt state tree. Only useful with master=false.

salt_file_root_guest_path : "/srv/salt"

Path to share the file root state tree on the VM. Only use with master=false.

salt_pillar_root_path : "salt/roots/pillar"

Path to share your pillar tree. Only useful with master=false.

salt_pillar_root_guest_path : "/srv/pillar"

Path on VM where pillar tree will be shared. Only use with master=true