system-config/doc/source/puppet.rst

title

Puppet Master

Puppet Master

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.

At a Glance

Hosts

• puppetmaster.openstack.org

Puppet

• modules/openstack_project/manifests/puppetmaster.pp

Projects

• https://puppetlabs.com/

Bugs

• https://storyboard.openstack.org/#!/project/748
• https://tickets.puppetlabs.com/

Resources

• Puppet Language Reference

Puppet Master

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

The cron jobs, current configuration files and more can be done with puppet apply but first some bootstrapping needs to be done.

You want to install these from puppetlabs' apt repo. There is a script in the root of the system-config repository that will setup and install the puppet client. After that you must install the puppetmaster and hiera (used to maintain secrets on the puppet master).

Puppet 3 masters can run on Trusty, Precise, and Centos 6.

sudo su -
git clone https://git.openstack.org/openstack-infra/system-config /opt/system-config/production
/opt/system-config/production/install_puppet.sh
apt-get install puppetmaster-passenger hiera hiera-puppet

Finally, install the modules, fix your hostname and use puppet apply to finish configuration:

bash /opt/system-config/production/install_modules.sh
echo $REAL_HOSTNAME > /etc/hostname
service hostname restart
puppet apply --modulepath='/opt/system-config/production/modules:/etc/puppet/modules' -e 'include openstack_project::puppetmaster'

Note: Hiera uses a systemwide configuration file in /etc/puppet/hiera.yaml and this setup supports multiple configurations. The two sets of environments that OpenStack Infrastructure uses 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. The keys needed are the keys referenced in your site.pp, their values are typically obvious (strings, lists of strings). /etc/puppet/hieradata/ and below should be owned by puppet:puppet and have mode 0711. The actual common.yaml file should have mode 0600.

Adding a node

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

sudo apt-get install puppet

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=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

Once the cert is signed, the puppet running orchestration will pick up the node and run puppet on it as needed.

Running Puppet on Nodes

In OpenStack's Infrastructure, puppet runs are triggered from a cronjob running on the puppetmaster which in turn runs a single run of puppet on each host we know about. We do not use the daemon mode of puppet agent because it experiences random hangs, and also does not allow us to control sequencing in any meaningful way.

The entry point for this process is /opt/system-config/production/run_all.sh

There are a set of nodes, which are configured in puppet as "override" nodes, which are run in sequence before the rest of the nodes are run in parallel. At the moment, this allows creation of git repos on the git slaves before creation of the master repos on the gerrit server.

Disabling Puppet on Nodes

In the case of needing to disable the running of puppet on a node, it's a simple matter of disabling the agent:

sudo puppet agent --disable

This will prevent any subsequent runs of the agent, including ones triggered globally by the run_all script. If, as an admin, you need to run puppet on a node where it has been disabled, you need to specify an alternate disable lock file which will allow your local run of puppet without allowing the globally orchestrated runs to occur:

sudo puppet agent --test --puppetdlockfile=/tmp/alt-lock-file

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.