system-config/doc/puppet.rst
Monty Taylor 6e27eede4a Turn off cron and document hiera.
Change-Id: I7a2db915d8849894a6b218980df6371378f0c77a
2012-07-21 18:38:51 -07:00

4.3 KiB

Puppet Master

Overview

Puppet agent is a mechanism use to pull puppet manifests and configuration from a centralized master. This means there is only one place that needs to hold secure information such as passwords, and only one location for the git repo holding the modules.

Puppet Master

The puppet master is setup using a combination of Apache and mod passenger to ship the data to the clients. To install this:

sudo apt-get install puppet puppetmaster-passenger

Files for puppet master are stored in a git repo clone at /opt/openstack-ci-puppet. We have a root cron job that automatically populates these from our puppet git repository as follows:

\*/15 * * * * sleep $((RANDOM\%600)) && cd /opt/openstack-ci-puppet && /usr/bin/git pull -q

The /etc/puppet/puppet.conf file then needs updating to point to the manifest and modules as follows:

[master]
# These are needed when the puppetmaster is run by passenger
# and can safely be removed if webrick is used.
ssl_client_header = SSL_CLIENT_S_DN
ssl_client_verify_header = SSL_CLIENT_VERIFY
manifestdir=/opt/openstack-ci-puppet/manifests
modulepath=/opt/openstack-ci-puppet/modules
manifest=$manifestdir/site.pp

Hiera

Hiera is used to maintain secret information on the puppetmaster.

We want to install hiera from puppetlabs' apt repo, but we don't want to get on the puppet upgrade train - so the process is as follows:

echo "deb http://apt.puppetlabs.com precise devel" > /etc/apt/sources.list.d/puppetlabs.list
apt-get update
apt-get install hiera hiera-puppet
rm /etc/apt/sources.list.d/puppetlabs.list
apt-get update

Hiera uses a systemwide configuration file in /etc/puppet/hiera.yaml which tells is where to find subsequent configuration files.

---
:hierarchy:
  - %{operatingsystem}
  - common
:backends:
  - yaml
:yaml:
  :datadir: '/etc/puppet/hieradata/%{environment}'

This setup supports multiple configuration. The two sets of environments that OpenStack CI users are production and development. production is the default is and the environment used when nothing else is specified. Then the configuration needs to be placed into common.yaml in /etc/puppet/hieradata/production and /etc/puppet/hieradata/development. The values are simple key-value pairs in yaml format.

Adding a node

On the new server connecting (for example, review.openstack.org) to the puppet master:

sudo apt-get install puppet

Then edit the /etc/default/puppet file to change the start variable:

# Start puppet on boot?
START=yes

The node then needs to be configured to set a fixed hostname and the hostname of the puppet master with the following additions to /etc/puppet/puppet.conf:

[main]
server=ci-puppetmaster.openstack.org
certname=review.openstack.org

The cert signing process needs to be started with:

sudo puppet agent --test

This will make a request to the puppet master to have its SSL cert signed. On the puppet master:

sudo puppet cert list

You should get a list of entries similar to the one below:

review.openstack.org  (44:18:BB:DF:08:50:62:70:17:07:82:1F:D5:70:0E:BF)

If you see the new node there you can sign its cert on the puppet master with:

sudo puppet cert sign review.openstack.org

Finally on the puppet agent you need to start the agent daemon:

sudo service puppet start

Now that it is signed the puppet agent will execute any instructions for its node on the next run (default is every 30 minutes). You can trigger this earlier by restarting the puppet service on the agent node.

Important Notes

  1. Make sure the site manifest does not include the puppet cron job, this conflicts with puppet master and can cause issues. The initial puppet run that create users should be done using the puppet agent configuration above.
  2. If you do not see the cert in the master's cert list the agent's /var/log/syslog should have an entry showing you why.