Start installing *nix agents
When a node is managed by Puppet, it runs a Puppet agent application, commonly called an agent. In this guide you install a *nixPuppet agent, which regularly pulls configuration catalogs from a Puppet master and applies them locally. This section includes how to sign the agent certificate request in the console.
These instructions assume you've installed PE.
How does a Puppet agent work?
Agents ensure that resources in a node stay in their desired state.
Periodically, a Puppet agent sends facts to a Puppet master and requests a catalog. The master compiles the catalog using several sources of information, and returns the catalog to the agent.
Once it receives a catalog, the agent applies it by checking each resource the catalog describes. If it finds any resources that are not in their desired state, the agent makes any changes necessary to correct them. (Or, in no-op mode, it reports on what changes would have been needed.)
After applying the catalog, the agent submits a report to its master. Reports from all the agents are stored in PuppetDB and can be accessed in the PE console.
Step 1a: Install an agent with the same OS and architecture as the Puppet master
Follow these steps if your agent node and your Puppet master have the same operating system and architecture. Otherwise, go to Step 1b.
Step 1b: Install an agent with a different OS and architecture than the Puppet master
Follow these steps if your agent node and your Puppet master do not have the same operating system and architecture. Otherwise, go to Step 1a.
This example describes adding an agent running Debian 6 on AMD64 hardware.As you complete the steps, modify the commands to match your agent's OS and architecture.
Step 2: Approve the certificate request
During installation, the agent node contacts the Puppet master and requests a certificate. To add the node to the console and to start managing its configuration, you must approve its certificate request.
- In the console, load a list of currently pending node requests by clicking Unsigned certs.
- Click the Accept All button to approve the request and add the node.
The Puppet agent can now retrieve configurations from the master the next time Puppet runs.
Step 3: Test the Puppet agent node
You can wait until Puppet runs automatically, or you can manually trigger Puppet runs.
By default, the agent fetches configurations from the Puppet master every 30 minutes. (You can
configure this interval in the puppet.conf file with the runinterval
setting.) However, you can manually trigger a Puppet run from the command line at
any time.
Next, learn how to configure your agents with Puppet code, beginning with pre-built chunks of Puppet code called modules.