Vagrant (crb, 2014 03-17)

VagrantWhy it’s awesome sauce AND a bag of

chips

What is Vagrant?

● Syntactic sugar around VMs○ Virtualbox○ VMWare○ LXC○ AWS○ Rackspace○ etc, etc, etc

What is Vagrant?

● Syntactic sugar around provisioning○ Chef○ Puppet○ CFEngine○ Scripts (bash, etc)○ etc, etc, etc

What is Vagrant?

● Five commands○ vagrant up○ vagrant provision○ vagrant ssh○ vagrant suspend○ vagrant destroy

● Actually 18 commands (v1.5)○ You really only use the 5 above.

It’s just Ruby

● Runs on Windows, Linux, OSX● Use all the programming constructs

○ loops○ variables○ etc

● Check the environment○ Great for working with Jenkins

● Bring in gems

It’s just a configuration file

● You’re building a configuration file○ Actions don’t happen immediately

● The Vagrant engine is intuitive○ (usually)

require 'vagrant-vbguest'

max_memory = 4 * 1024 # This is in megabytesVagrant.configure("2") do |config| config.vm.provider :virtualbox do |vb, override| override.vm.box = "precise64" override.vm.box_url = "http://some.place.com/some/path.box"

vb.customize ["modifyvm", :id, "--memory", max_memory] endend

require ‘vagrant-lxc’

max_memory = 4 * 1024 # This is in megabytesVagrant.configure("2") do |config| config.vm.provider :lxc do |lxc, override| override.vm.box = "precise64" override.vm.box_url = "http://some.otherplace.com/some/path.box"

lxc.customize 'cgroup.memory.limit_in_bytes', "#{max_memory}M" endend

require 'vagrant-vbguest'require ‘vagrant-lxc’

max_memory = 4 * 1024 # This is in megabytesVagrant.configure("2") do |config| config.vm.provider :virtualbox do |vb, override| …. end

config.vm.provider :lxc do |lxc, override| …. endend

Provider details

● Provider is specified in “vagrant up”○ Other commands detect the provider

● There are dozens of providers○ Virtualbox, VMWare, LXC, Docker○ AWS, Joyent, Rackspace, DigitalOcean○ OpenStack, Parallels

● Writing your own isn’t all that hard○ Prior art is very helpful, as is mailing list and IRC

Shared Folders

● By default, the folder with the Vagrantfile is shared into /vagrant○ Can be changed

● Can add more shared folders○ The provisioners already do this

● For cloud VMs, “shared” means “rsync’ed on demand”.

Vagrant.configure("2") do |config| chefdir = ‘.’ config.vm.provision :chef_solo do |chef| chef.roles_path = “#{chefdir}/roles”

chef.run_list.clear chef.add_role "container" endend

Vagrant.configure("2") do |config| chefdir = ‘devops/chef’ config.vm.provision :chef_solo do |chef| chef.roles_path = “#{chefdir}/roles”

chef.run_list.clear chef.add_role "container" endend

Vagrant.configure("2") do |config| config.vm.provision :shell, inline: “some bash code here”

config.vm.provision :shell, path: “path/to/script” # Must be relative to Vagrantfile directoryend

Provisioner details

● The order provisioners are declared matters.○ If one fails, the remainder will not run.

● Can mix-and-match○ Normally one chef/puppet/etc and several shell

Multiple VMs

● Can launch 1-N VMs○ Each VM must have a unique name

● Each VM can have a different:○ provider (one and only one)○ set of provisioners○ configuration, including:

■ network interface

Vagrant.configure("2") do |config| config.vm.define “web” do |web| web.vm.provision ‘shell’, inline: “echo “web” > /etc/vagrant_purpose” web.vm.provider :chef-solo do |chef| end end

config.vm.define “database” do |database| database.vm.provision ‘shell’, inline: “echo “database” > /etc/vagrant_purpose” database.vm.provider :puppet do |puppet| end endend

Vagrant.configure("2") do |config| config.vm.provider :virtualbox do |vb, override| ... end

(‘web’, ‘database’).each do |name| config.vm.define name do |machine| machine.vm.provision ‘shell’, inline: “echo “#{name}” > /etc/vagrant_purpose” end endend

So what?

● This isn’t just another cool tool.● Sometimes, all you need is simpler controls.

○ Everything has always been possible, just most things are too expensive to build.

Clone production

● Dev and QA should be clones of Prod○ Prod doesn’t run on a single server○ So, why does QA and Dev?

Setup load-testing

● Use a cloud provider (AWS, etc)● A Vagrantfile that has:

○ Your production structure○ Your load-testing systems (Tsung, JMeter, etc)

● Running a load test is now just:○ vagrant up○ vagrant ssh load1 -c “/vagrant/bin/run_load_test.sh”

Jenkins and Testing

● Testing should be in a clone of Production○ The best clone is what you’ll build Production from

● Jenkins can integrate with Vagrant○ vagrant up○ vagrant ssh -c “/vagrant/bin/run_tests.sh”

■ This will return the exit code properly

Vagrant.configure("2") do |config| # Configure the AWS provider here NUM = # Figure out how many instances to run (1 .. NUM).each do |index| config.vm.define “test#{index}” do |test| test.vm.provision ‘shell’, inline: “echo “test#{index}” > /etc/vagrant_purpose” test.vm.provider :aws do |aws| aws.tags = { ‘Name’ => “#{aws.tags[‘Name’]}-test#{index}” } end end endend

Automate Golden Images

$ vagrant up --provider=aws$ ec2-create-image \ `cat .vagrant/machines/default/aws/id` \ --name “my_new_ami”$ vagrant destroy -f

Putting it all together (A Crazy Idea)

● Let developers manage server changes○ Provisioners for a project are checked into that

project’s repository○ Developers can make changes○ Vagrant lets them test out changes in a clone of

production○ Devops participates in code reviews (as needed)

■ Devops has veto over changes to devops/ directory and code.

Putting it all together (A Crazy Idea)

● Devops is no longer responsible for:○ Server changes

● Devops IS responsible for:○ Validating proposed server changes○ Ensuring the pipeline for server changes○ Training the developers to own their server changes

● Job changes○ Build the engine instead of pulling the rickshaw

Community is key

● https://github.com/rails/rails-dev-box● https://github.com/jpettersson/vagrant-rails-

project-box○ Same thing, but with Chef

● http://manuel.manuelles.nl/blog/2013/07/23/developing-ruby-on-rails-on-windows/○ Same thing, but on Windows

Questions?

Rob [email protected] on Twitterrobkinyon on IRCwww.greenfishbluefish.com