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admin-guide/puppet/puppet_client.md

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+# Puppet Client
+
+The Puppet Agent updates the configuration on the node. It automatically runs regulary, for configuration details check the [configuration guide](../configuration/puppet_agent).
+
+The puppet client can be manually triggered/run by calling following command on the client:
+
+```bash
+puppet agent -t
+```
+
+To only check what the client would actually do, without actually changing the systems configuration/files/etc. you can use the `--noop` option:
+
+```bash
+puppet agent -t --noop
+```
+
+To instruct the puppet client to use a specific puppet environment use:
+
+```bash
+puppet agent -t --environment my_environment
+```
+The client will keep this environment until
+- either the puppet environment is removed from the server (i.e. the client will do a fallback to the default environment)
+- you manually change the environment again
+
+
+
+## Attach Node to Different Puppet Server
+
+For testing purpose you might want to change the Puppet server to which a test node is attached to. To do so do, change the ``server`` in the ``[main]`` section of ``/etc/puppetlabs/puppet/puppet.conf`` accordingly.
+
+Then delete the current host and CA certficate and the CRL:
+
+   #. ``rm /etc/puppetlabs/puppet/ssl/certs/*``
+   #. ``rm /etc/puppetlabs/puppet/ssl/crl.pem``
+
+Finally run the puppet agent again.