An Introduction to DevOps with Chef

Rethinking IT: An Introduction
to DevOps with Chef
Julian C. Dunn
Senior Consultant, Opscode
<jdunn@opscode.com>
Wednesday, October 2, 13

Topics
• Rethinking IT with DevOps
• What Chef is and how it helps
• Flavors of Chef
• Use cases and demo

I came to hear about
Chef.

Why are you throwing
DevOps into this?

It’s how Chef works best
• Chef is a tool.
• It works best when developers and operations
work well together
• You don’t need “DevOps” for Chef to be successful.
• But it helps.

What is this DevOps?
Sounds like a buzzword.

DevOps: Aligning Objectives
• Cultural and Professional
movement
• Development and
Operations working
together
• Leveraging ideas &
processes from other
industries
• To enable the business

Technology: Business Engaging Customers

Speed of Globalization
• 40 years for container
ships to move 70% of
seaborne trade
• 22 years for internet
access to reach 78%
penetration in North
America

Globalization
• Online retail sales are 7%
of all retail sales
• 75% of 2011 Thanksgiving
shoppers did so online
• 42% of all retail
purchases were
influenced by online
research – accounting for
~50% of total retail
spending.WTO Trends in Globalization
http://www.wto.org/english/res_e/booksp_e/anrep_e/wtr08-2b_e.pdf
http://www.ﬂickr.com/photos/duke_raoul/2261478794/sizes/l/in/photostream/

Mobile Devices
• 42% are smartphones
• 58% will be on next
purchase
• 4.2 Billion phones
globally for 7.09 Billion
people (USCB)
http://ssiknowledgewatch.com/2012/05/09/cell-phones-approach-total-penetration-globally-with-smartphones-moving-toward-market-dominance-2/
http://www.brightsideofnews.com/news/2011/1/26/digital-divide-global-household-penetration-rates-for-technology.aspx?pageid=1

Software: The Interface
for Consumtpion

Drivers of IT Innovation
The Result: The Coded Business
How: Redeﬁnition of how to use technology to
create business value
Why: To rapidly deliver experiences, goods and
services to customers
What: Consumer-facing businesses

The Rise of the Coded Business
• Speed of change > speed of skills development
• IT is moving from the back office to the front office
• Digital consumption
• Technology directly supports customer interactions
• Companies must move faster to compete

Patterns of the Coded Business
Business
Agility
Development
Velocity and
Consistency
Continuous
Delivery
IT
IT enables Business Agility and
becomes a strategic advantage
rather than a cost center.

The Coded Business: Coming to Every Enterprise
Manufacturing Financial
Services
Retail
Media and
Entertainment
High
Technology
Healthcare

Scale x Complexity > Skills

DevOps...
• Cultural and professional movement
• Grew directly from people who have experienced
this transition
• Applies directly to traditional IT
• Applies directly to other systems of survival in
our culture

DevOps: CAMS
• Culture
• Automation
• Measurement
• Sharing

Open Communication
• Developers &
Operations talk and
listen to one another
• Production & build
metrics are available
to all
• Current infrastructure
is documented

Incentive & Responsibility Align
• Create awesome
customer experiences
• Responsibility &
accountability, not
authority
• Responsible for your
own uptime

Respect
• You don’t have to be
everyone’s best friend
• But you do need to
recognize
contributions and treat
each other well
• No asshole rule

Culture: Trust
• Trust that everyone is
competent & working
toward the common
goals
• Without trust, the
tools don’t matter

DevOps: CAMS
• Culture
• Automation
• Measurement
• Sharing
• Chef is (part of) “A”. Works best with C, M and S.

Infrastructure
Automation with Chef

http://www.ﬂickr.com/photos/steffenz/337700069/
http://www.ﬂickr.com/photos/kky/704056791/
Applications

Infrastructure
http://www.ﬂickr.com/photos/sbh/462754460/

http://www.ﬂickr.com/photos/philliecasablanca/3354734116/
• Networking
• Files
• Directories
• Symlinks
• Mounts
• Routes
• Users
• Groups
• Tasks
• Packages
• Software
• Services
• Configuration
• Other Stuff
Collection of Resources

Acting in Concert
http://www.ﬂickr.com/photos/glowjangles/4081048126/

To Provide a Service
http://www.ﬂickr.com/photos/28309157@N08/3743455858/

And it Evolves
http://www.ﬂickr.com/photos/16339684@N00/2681435235/

Application Server
See Node

Application Server
Application Database
See Nodes

Application Server
Application Databases
See Nodes Grow

Application Servers
See Nodes Grow

Application Servers
Load Balancer
See Nodes Grow

Application Servers
Load Balancers
See Nodes Grow

Application Servers
Application Database Cache
Load Balancers
See Nodes Grow

Application Servers
Load Balancers
Tied Together with Configuration

Application Servers
Load Balancers
Floating IP?
Infrastructure is a Snowflake

Load Balancers
Application Servers
NoSQL
Database Slaves
Application Cache
Database Cache
Database
Evolving Complexity

Complexity Increases Very Quickly
DC1
DC3
DC2

Configuration Management
http://www.ﬂickr.com/photos/philliecasablanca/3354734116/

Golden Images are not the answer
• Gold is heavy
• Hard to transport
• Hard to mold
• Easy to lose
configuration detail
http://www.ﬂickr.com/photos/garysoup/2977173063/

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
Typical Infrastructure

JBoss App
Memcache
Postgres Slaves
Postgres Master
NagiosGraphite
• Move SSH off port 22
• Let’s put it on 2022
New Compliance Mandate!

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
• edit /etc/ssh/sshd_config
1 2
3
4
5
6
6 Golden Image Updates

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
• Delete, launch
1 2
3 4 5 6 7
8 9
10 11
12
• Repeat
• Typically manually
12 Instance Replacements

• Don’t break anything!
• Bob just got fired =(
5
JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite 1 2
4 5 6 7
8 9
10 11
12
3
Done in Maintenance Windows

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
• Invalid configs!
Different IP Addresses?

Configuration Desperation
http://www.ﬂickr.com/photos/francoforeshock/5716969942/

Chef Solves This Problem
• But you already
guessed that, didn’t
you?

Chef is Infrastructure as Code
• Programmatically
provision and
configure
• Treat like any other
code base
• Reconstruct business
from code repository,
data backup, and bare
metal resources.http://www.ﬂickr.com/photos/louisb/4555295187/

Programs
• Chef generates
configurations directly
on nodes from their run
list
• Reduce management
complexity through
abstraction
• Store the configuration
of your programs in
version control
http://www.flickr.com/photos/ssoosay/5126146763/

Declarative Interface to Resources
• Define Policy
• Say what, not how
• Pull not Push
http://www.ﬂickr.com/photos/bixentro/2591838509/

That Looks Like This
package "apache2"
template "/etc/apache2/apache2.conf" do
source "apache2.conf.erb"
owner "root"
group "root"
mode "0644"
variables(:allow_override => "All")
notifies :reload, "service[apache2]"
end
service "apache2" do
action [:enable,:start]
supports :reload => true
end

Ohai
"languages": {
"ruby": {
},
"perl": {
"version": "5.14.2",
"archname": "x86_64-
linux-gnu-thread-multi"
},
"python": {
"version": "2.7.3",
"builddate": "Aug 1
2012, 05:14:39"
},
"php": {
"version":
"5.3.10-1ubuntu3.6",
"builddate": "(cli)
(built: Mar"
}
},
"network": {
"interfaces": {
"lo": {
"mtu": "16436",
"flags": [
"LOOPBACK", “UP","LOWER_UP"
],
"encapsulation": "Loopback",
"addresses": {
"127.0.0.1": {
"family": "inet",
"netmask": "255.0.0.0",
"scope": "Node"
},
"::1": {
"family": "inet6",
"scope": "Node"
}
},
},
"eth0": {
"type": "eth",
"number": "0",
"kernel": {
"name": "Linux", "release":
"3.2.0-32-virtual",
"version": "#51-Ubuntu SMP Wed
Sep 26 21:53:42 UTC 2012",
"machine": "x86_64",
"modules": {
"isofs": {
"size": "40257",
"refcount": "0"
},
"acpiphp": {
"size": "24231",
"refcount": "0"
}
},
"os": "GNU/Linux"
},
"os": "linux",
"os_version": "3.2.0-32-virtual",
"ohai_time": 1369328621.3456137,

execute "load sysctl" do
command "/sbin/sysctl -p"
action :nothing
end
bytes = node['memory']['total'].split("kB")[0].to_i * 1024 / 3,
pages = node['memory']['total'].split("kB")[0].to_i * 1024 / 3 / 2048
# adjust shared memory and semaphores
template "/etc/sysctl.conf" do
source "sysctl.conf.erb"
variables(
:shmmax_in_bytes => bytes,
:shmall_in_pages => pages
)
notifies :run, "execute[load sysctl]", :immediately
end
Decide what to declare

Recipes and Cookbooks
• Recipes are collections of
Resources
• Cookbooks contain recipes,
templates, files, custom
resources, etc
• Code re-use and modularity
http://www.flickr.com/photos/shutterhacks/4474421855/

Run Lists
Server
ServerServer
Server
chef-server
API chef-client
“recipe[ntp::client]”
node
ntp
client.rb

Run Lists
Server
ServerServer
Server
chef-server
API chef-client
“recipe[ntp::client]”,
“recipe[openssh::server]”
node
ntp
client.rb
openssh
server.rb

Run Lists
Server
ServerServer
Server
chef-server
API chef-client “recipe[ntp::client]”,
“recipe[openssh::server]”,
“recipe[apache]”,
“recipe[php]”
node
ntp
client.rb
openssh
server.rb
apache
default.rb
php
default.rb

Roles
name "base"
description "base"
run_list [
"recipe[selinux::disabled]",
"recipe[etchosts]",
"recipe[yum::epel]",
"recipe[debugtools]"
]
name "webserver"
description "webserver server"
run_list [
"role[base]",
"recipe[nginx::server]"
]

Roles
Role
Recipe
Recipe
Recipe
Role
Role
Recipe
Recipe
RecipeRole
Recipe
Server
ServerServer
Server
chef-server
API
Knife

Roles
Server
ServerServer
Server
chef-server
API chef-client
“role[webserver]”
node
ntp
client.rb
openssh
server.rb
apache
default.rb
php
default.rb

Roles
Server
ServerServer
Server
chef-server
API
chef-client
“role[webserver]”
node
ntp
client.rb
openssh
server.rb
apache
default.rb
php
default.rb
chef-client
“role[database]”
node
ntp
client.rb
openssh
server.rb
mysql
server.rb

http://www.ﬂickr.com/photos/kathycsus/2686772625
• IP addresses
• Hostnames
• FQDNs
• Search for nodes
with Roles
• Find configuration
data
Search: Dynamic Infrastructure

Search for Nodes
pool_members = search("node","role:webserver")
template "/etc/haproxy/haproxy.cfg" do
source "haproxy-app_lb.cfg.erb"
owner "root"
group "root"
mode 0644
variables :pool_members => pool_members.uniq
notifies :restart, "service[haproxy]"
end

Pass results into Templates
# Set up application listeners here.
listen application 0.0.0.0:80
balance roundrobin
<% @pool_members.each do |member| -%>
server <%= member[:hostname] %> <%= member[:ipaddress] %>:>
weight 1 maxconn 1 check
<% end -%>
<% if node["haproxy"]["enable_admin"] -%>
listen admin 0.0.0.0:22002
mode http
stats uri /
<% end -%>

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
So when this...

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
... becomes this ...

JBoss App
Memcache
PostgreSQL Slaves
PostgreSQL Master
NagiosGraphite
...this can happen automatically

NagiosGraphite
JBoss App
Memcache
PostgreSQL
Slaves
To Add a New Server…
• 2x Web Server Configurations
• 2 Web Server Restarts
• 4x Database Configurations
• 8x Firewall Configurations
• DNS Service
• Network Configuration
• Deployer
• 8x Monitoring Changes
20+ Changes
12+ New Infrastructure
Dependencies
4+ Hours
Count the Resources

NagiosGraphite
JBoss App
Memcache
PostgreSQL
Slaves
To Add a New Server…
• 2x Web Server Configurations
• 2 Web Server Restarts
• 4x Database Configurations
• 8x Firewall Configurations
• DNS Service
• Network Configuration
• Deployer
• 8x Monitoring Changes
20+ Changes
12+ New Infrastructure
Dependencies
4+ Hours
Count the Resources
Add 1 server
20+ Changes

Managing Complexity Later

Managing Complexity Later
We added:
• Load Balancers
• MemCache
• Search Appliances
• Lots of VM’s
• More Scale
Exponential Increase In:
• Configuration Changes
• Infrastructure Dependencies
• Skills Needed
• Greater Risk

And at Greater Scale...

And at Greater Scale...
How Do we Manage
This
at Cloud Scale?
• Thousands of
infrastructure
dependencies and
configurations needed
for each change.
• Huge Amounts of Time
• Increased Cost of
Correction of Manual
Errors
• Huge Need for Talent
• Risk of Critical Skills
Shortage

Automation is a Journey
Full
Automation
Common
Automation
Tasks:
Scripts, OS
Compliance,
Updates, etc.
Configuration
ManagementDiscovery and
Visibility
Application
Management
Continuous
Deployment
The Path to the Coded Business

Flavors of Chef Server

Landscape of Chef-Managed Infrastructure

• SaaS, hosted by Opscode
• Manage up to 50,000 servers
• Industry-leading SLAs
• 24x7x365 Support Options
• Get up and running quickly
• Pay/grow as you need
Hosted Enterprise Chef

• All the power of Hosted Enterprise, behind
the firewall
• Delivered as enterprise software
• Implementation consulting customized to
customer’s needs
Enterprise Chef

• Core components of Chef Server
developed as open source
• No enterprise features (LDAP, HA, etc.)
but many people use it successfully
• Community support
Open Source Chef Server

Learn Chef!

Let’s Learn Chef!
• https://learnchef.opscode.com/
• Next meetup: Hands on. Bring laptops!
• Feel free to get started early

Thanks
• Julian Dunn
• jdunn@opscode.com
• @julian_dunn
• www.juliandunn.net

An Introduction to DevOps with Chef

More Related Content

Similar to An Introduction to DevOps with Chef (20)

More from Julian Dunn (20)

Recently uploaded (20)

An Introduction to DevOps with Chef