Puppet is a cross
platform framework enabling system administrators to perform common tasks using
code. The code can do a variety of tasks from installing new software, to
checking file permissions, or updating user accounts. Puppet is great
not only during the initial installation of a system, but also throughout the
system's entire life cycle. In most circumstances puppet will be used
in a client/server configuration.
Preconfiguration
Prior to
configuring puppet you may want to add a DNS CNAME record
for puppet.example.com, where example.com is your domain. By
defaultPuppet clients check DNS for
puppet.example.com as the puppet server name, or Puppet Master.
If you do not
wish to use DNS, you can add entries to the server and client /etc/hosts file.
For example, in the Puppet server's /etc/hosts file add:
127.0.0.1 localhost.localdomain localhost puppet
192.168.1.17 puppetclient.example.com puppetclient
On each Puppet client,
add an entry for the server:
192.168.1.16 puppetmaster.example.com puppetmaster puppet
Replace the
example IP addresses and domain names above with your actual server and client
addresses and domain names.
Installation
To install Puppet,
in a terminal on the server enter:
sudo apt-get install puppetmaster
On
the client machine, or machines, enter:
sudo apt-get install puppet
Configuration
Create
a folder path for the apache2 class:
sudo mkdir -p /etc/puppet/modules/apache2/manifests
Now setup some resources
for apache2. Create a file /etc/puppet/modules/apache2/manifests/init.pp containing
the following:
class apache2 {
package { 'apache2':
ensure => installed,
}
service { 'apache2':
ensure => true,
enable => true,
require => Package['apache2'],
}
}
Next, create a node file /etc/puppet/manifests/site.pp with:
node 'puppetclient.example.com' {
include apache2
}
The final step for this
simple Puppet server is to restart the daemon:
sudo service puppetmaster restart
Now everything is
configured on the Puppet server, it is time to configure the client.
First, configure the Puppet agent
daemon to start. Edit /etc/default/puppet, changing START to
yes:
START=yes
Then start the service:
sudo service puppet start
View the client cert
fingerprint
sudo puppet agent --fingerprint
Back on the Puppet server,
view pending certificate signing requests:
sudo puppet cert list
On the Puppet server,
verify the fingerprint of the client and sign puppetclient's cert:
sudo puppet cert sign puppetclient.example.com
On the Puppet client,
run the puppet agent manually in the foreground. This step isn't strictly
speaking necessary, but it is the best way to test and debug the puppet
service.
sudo puppet agent --test
Check /var/log/syslog on
both hosts for any errors with the configuration. If all goes well the apache2 package
and it's dependencies will be installed on the Puppet client.