Chef Metal

Manage Your Clusters

Like You Manage Your Machines

John Keiser

Chef Lead - Team Ronin

Resident Mad Scientist

@jkeiser2

Ye Olde Ops Playbook

Chef!

package 'apache2' do
  version '2.0'end
template '/etc/httpd.conf'
service 'apache2'

Chef!

Repeatable
Self-Documenting
Flexible
Self-Healing
Versionable
Readable
Testable

YE NEWE OPS PLAYBOOK

Clusters IN OUR DREAMS

real Clusters

the Cluster Litany

Version?

Test?

Re-create?

Manage Machines?

Add Capacity?

Info out of date :(

My memory sucks

Nothing is checked in anywhere

knife ec2 create --args=10,000,000

ssh? winrm? IP?

Which cloud? Or container? Or VM?

I JUST WANT TO CONVERGE

My First Cluster


  machine 'db' do    recipe 'mysql'  end
  machine 'web1' do    recipe 'apache'  end

My First Cluster

  > CHEF_DRIVER=vagrant:~/vms  > chef-client -z cluster.rbRecipe: talk1::cluster
  * machine[db] action create    - run vagrant up db    - write file /etc/chef/client.rb on db
      Starting Chef Client, version 11.8.2
      Recipe: mysql::default        * file[/etc/mysql.txt] action create
          - create new file /etc/mysql.txt      Chef Client finished, 1 resources updated    - run 'chef-client' on db
  * machine[web1] action create    - run vagrant up web1    - write file /etc/chef/client.rb on web1    - run 'chef-client' on web1 Chef Client finished, 2 resources updated

What.

machine resource

Drivers

WHAT.

machine resource

Drivers

Cloud
VMs
Containers
Metal (Razor, etc.)

It's Chef

chef-client

It's Recipes

  private_key 'crypt'
  chef_data_bag_item 'x/y' do    secret_path 'crypt'  end
  machine 'mydb' do
    file '/etc/crypt', 'crypt'  end

It's Unified


metal login [node]
metal execute [node]
metal delete [node]
metal converge [node]

Adding a New Machine


  machine 'db' do    recipe 'mysql'  end
  machine 'web' do    recipe 'apache'  end
 machine 'web2' do   recipe 'apache' end

Idempotence!

  > chef-client -z -o cluster.rb Recipe: talk1::cluster
  * machine[db] action create (up to date)  * machine[web1] action create (up to date)  * machine[web2] action create    - run vagrant up web2    - write file /etc/chef/client.rb on web2
      Starting Chef Client, version 11.8.2
      Recipe: apache::default        * file[/etc/apache.txt] action create
          - create new file /etc/apache.txt      Chef Client finished, 1 resources updated    - run 'chef-client' on web2
 Chef Client finished, 1 resource updated

Recycle, Reuse, Renew

Let's Do EC2


CHEF_DRIVER=fog:AWS:default

Yay

  > chef-client -z cluster.rb

Continuous Integration

Continuous Integration

Check in Metal recipe
chef-client on Jenkins node
...

Provisioning nodes

Upload cluster cookbook
Wait 5 minutes
...

Growing the cluster


  machine 'db' do    recipe 'mysql'  end
  machine 'web' do    recipe 'apache'  end
 machine 'web2' do   recipe 'apache' end

Upscaling

Upscaling

Upscaling is just adding new nodes
Chef recipes are code
Use a variable for your for loop
Drive it from your own monitor data


1.upto(num_webservers) do  machine "webserver#{i}" do
    recipe 'apache'    tag 'webserver'  endend

Downscaling

Delete what you don't need.

   search('tags:webserver') do |node|    node.name =~ /^webserver(\d+)$/    if $1.to_i > num_webservers      machine node.name do        action :delete      end    end  end

Parallelism


  with_machine_batch 'my_batch'

  1.upto(50) do |i|
    machine "webserver#{i}" do
      recipe 'apache'
    end
  end

Provisioners

There are lots already

chef-metal-fog

chef-metal-vagrant

chef-metal-ssh

chef-metal-lxc

chef-metal-docker

chef-metal-vsphere

Between them, we support

EC2 - DigitalOcean - Openstack - SoftLayer - VSphere

VirtualBox - VMWare Fusion

Bare Metal (SSH, no PXE yet)

LXC - Docker

Making a Driver

Extend the Driver interface
Implement 4 methods
...

driver.allocate_machine(...)

Reserves / purchases a machine

Optionally starting spinup

Short execution time

driver.ready_machine(...)

Starts up machine

Waits for machine to be ready

Returns Machine object

The machine object

Execute commands
Manipulate files
Converge machine

It's already there

UnixMachine

WindowsMachine

Transports

Used by Unix/WindowsMachine
Handle execution and file manipulation

Already there:

SSHTransport

WinRMTransport

LXCTransport

DockerTransport

Convergence Strategies

Handle installation of chef and converge

"idempotent bootstrap"

Already there:

InstallCached

InstallSh

InstallMsi

NoConverge

class MyProvisioner < Provisioner  def allocate_machine(ah, machine, options)    id = machine.location['id']    if id
      server = lookup_server(id)    else
      server = create_server(options)
      machine.location = {        'id' => server.id      }    end
  endend

Parallelism

allocate_machines

ready_machines

Other methods

connect_to_machine

delete_machine

stop_machine

MACHINE Options

Shape of the machine

Freeform Hash

Driver decides what goes in it

Not stored anywhere

Example Vagrant options:


  machine_options :vagrant_options => { 'vm.box' => 'precise64' },
    :vagrant_config => 'config.vm.synced_folder "~/code", "/mnt/code"'

Example EC2 options:


  machine_options :bootstrap_options => {
    :image_id => 'ami-2f726546',    :flavor_id => 'c1.xlarge'
  }

Different Machines Are Different


 machine 'webserver' do
   driver 'fog:GoogleCloud:MyAccount'   recipe 'webserver'
 end
 with_driver 'fog:AWS:default', :region => 'us-west-1' do
   machine 'monitor' do
     recipe 'monitor'
   end
   machine 'another_webserver' do
     machine_options :region => 'us-east-1'     recipe 'webserver'
   end end

1.0 Soon.

After 1.0:

More Drivers

Lightweight Provisioning

More Cluster Resources

Key Management

How you can help

Write drivers
Use it
Send feedback
File and fix bugs

https://github.com/opscode/chef-metal