Hiera is Puppet’s built-in key/value data lookup system. By default, it uses simple YAML or JSON files, although you can extend it to work with almost any data source. Hiera is the most flexible way to get configuration data into Puppet. Hiera is immensely powerful, and with great power comes great responsibility. Specifically, you’re responsible for making your infrastructure maintainable and legible, both for your co-workers and for your future self.
Let’s Started
The default location for the global hiera.yaml is $confdir/hiera.yaml. Depending on your platform, that’s usually at /etc/puppetlabs/puppet/hiera.yaml. You can use the hiera_config setting in puppet.conf to change the location of the global hiera.yaml.
root@puppet:~# cat /etc/puppetlabs/puppet/puppet.conf .... .... [master] vardir = /opt/puppetlabs/server/data/puppetserver logdir = /var/log/puppetlabs/puppetserver rundir = /var/run/puppetlabs/puppetserver pidfile = /var/run/puppetlabs/puppetserver/puppetserver.pid codedir = /etc/puppetlabs/code hiera_config = /etc/puppetlabs/code/environments/production/hiera.yaml .... .... root@puppet:~#
Hiera Config
Hiera’s config file is called hiera.yaml. It configures the hierarchy for a given layer of data.
root@puppet:~# cat /etc/puppetlabs/code/environments/production/hiera.yaml
---
:merge_behavior: deeper
:backends:
- yaml
:logger: console
:yaml:
:datadir: "/etc/puppetlabs/code/environments/%{environment}/hieradata"
:hierarchy:
- "common"
root@puppet:~#
root@puppet:~# cat /etc/puppetlabs/code/environments/production/hieradata/common.yaml
---
krishna: "1000"
chandra: "5000"
prajapati: "10000"
root@puppet:~#
After modifying hiera configs, restart puppetserver services.
Accessing hiera data using cli
Once you have the hiera data ready in the puppet server, you can check the values using hiera CLI.
root@puppet:~# hiera -c /etc/puppetlabs/code/environments/production/hiera.yaml prajapati environment=production 10000 root@puppet:~# root@puppet:~# hiera -c /etc/puppetlabs/code/environments/production/hiera.yaml krishna environment=production 1000 root@puppet:~# root@puppet:~# (This record doesn't exist in hiera, therefore it's giving nil) root@puppet:~# hiera -c /etc/puppetlabs/code/environments/production/hiera.yaml chandr environment=production nil root@puppet:~# root@puppet:~# hiera -c /etc/puppetlabs/code/environments/production/hiera.yaml chandra environment=production 5000 root@puppet:~#
Conclusion:
We have successfully setup hiera. Now, hiera is ready to serve the parameters.
Enjoy !!!