install a puppet agent (client) on AWS CE2 CentOS

$ sudo yum install puppet
$ puppet --version
2.7.22

## make sure your puppet server should install puppet version higher than this. (it's 3.2.3 on my puppet server)

## check your host name as in the /etc/puppet/manifests/nodes.pp file to make sure what you want to include.

$ puppet agent --server=puppet.katdc.com --debug --test --waitforcert=60

## on your puppet server side, to certify this hist

$ puppet cert list --all

## if you see a host name, such as AAA not signed.

$ puppet cert sign AAA

## back to your puppet agent, it will keep going and install all the categories.