This document summarizes a workshop about using CloudInit to bootstrap cloud instances. CloudInit allows giving instances a user-data file on first start that can configure the instance. Examples shown include setting hostname, importing SSH keys, installing packages, executing scripts. The document provides advice to use existing recipes or write your own scripts in YAML or other languages to declare configuration.

1. Xebia Workshop
CloudInit
Xebia: OpenCSI:
Bertrand Dechoux Bruno Bonfils
Charles Blonde
Cyrille Le Clerc
Emmanuel Servent
Eric Briand
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2. Introduction
 Goal: bootstrap a cloud instance
 How: give a file as parameter for the first
instance start
▶ Retrievedfrom http://169.254.169.254/latest/user-data
▶ May be a multipart file
 Ubuntu project, exist for RPM based systems
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3. Some recipes examples
 Set the hostname
 Import SSH keys
 Declare apt mirror
 Install packages
 Execute commands
 Execute scripts
 Bootstrap Puppet / Chef
Detailed sample : http://bazaar.launchpad.net/~cloud-init-dev/cloud-init/trunk/view/head:/doc/examples/cloud-config.txt
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4. Advices
 CloudInit is not very well documented, use the
source, good luck!
 Choose to use existing recipes or write your own
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5. cloud-config: the key CloudInit script
#cloud-config
timezone: Europe/Paris
packages:
- puppet
- java-1.6.0-openjdk
- tomcat6
- tomcat6-webapps
runcmd:
- [service, tomcat6, start]
- [chkconfig, tomcat6, on]
Declarative YAML based configuration
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6. My own shell script
#!/usr/bin/env bash
instanceId=$(curl http://169.254.169.254/latest/meta-data/instance-id)
fqdn="$instanceId.aws.labs.opencsi.com"
sed -i.bak "s/HOSTNAME=.*/HOSTNAME=${fqdn}/" /etc/sysconfig/network
hostname ${fqdn}
echo "127.0.0.1 $id $fqdn" >> /etc/hosts
# Now bootstrap puppet
puppetd --no-daemonize --onetime -v --server=puppetmaster.aws.labs.opencsi.com
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7. My own shell script
#!/usr/bin/env python
...
# INJECT DATABASE URL IN CATALINA.PROPERTIES
f = open(catalinaBase + '/conf/catalina.properties', 'ab')
f.write('nn# BEGIN OF ADDED BY CLOUD-INIT #n')
f.write('jdbc.url=jdbc:mysql://my-db-host:3306/petclinicn')
f.write('jdbc.username=petclinicn')
f.write('jdbc.password=petclinicn')
f.write('nn# END OF ADDED BY CLOUD-INIT #n')
f.close()
# DOWNLOAD AND DEPLOY WAR
url = 'http://my-nexus/fr/xebia/.../1.0.2/petclinic-1.0.2.war'
URLopener().retrieve(url, catalinaBase + '/webapps/petclinic.war')
print('Downloaded ' + url + ' to ' + filename)
Inject database config in Tomcat
Deploy war
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8. CloudInit resources
 https://help.ubuntu.com/community/CloudInit
 https://code.launchpad.net/~cloud-init-dev/
cloud-init/trunk
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9. The Workshop
“Discover Java Infra as Code with Amazon AWS”

http://code.google.com/p/xebia-france/wiki/
JavaInfrastructureAsCodeWithAmazonAwsWorkshop
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