Templates
Often you’ll want to maintain configuration files for applications
that are different between servers. If you have a couple of
configurations, it’s easy enough to maintain multiple files, but what if
you have a very large number of differing configurations? We can manage
this situation by writing ERB templates and populating the templates with
node-specific information. This is done in Puppet with the template()
function:
file { "apache-site": path => "/etc/apache2/sites-available/$fqdn", require => Package["apache2"], content => template("apache-site.erb"), notify => Exec["a2ensite"], } exec { "a2ensite $fqdn": notify => Service["apache2"], creates => "/etc/apache2/sites-enabled/$fqdn", }
Here we have a file resource that creates an Apache config file
named by the fqdn
variable. We’ll
assume that Facter is populating this variable with the fully qualified
domain name of our server. The file
contents are generated by an ERB template and then it notifies an exec
that enables the site and notifies Apache to restart. Next we’ll write our
template and place it in the expected location at /etc/puppet/templates/apache-site.erb:
<VirtualHost *:80> DocumentRoot /var/www/ ServerName <%= name %> <Directory /var/www/> allow from all Options -Indexes </Directory> </VirtualHost>
This is just a normal Apache vhost stanza, with the exception of the
inline included name
variable. All variables in the current scope are available to you in this manner and out-of-scope variables in other classes ...
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