Puppet agent doesn’t retrieve files from master

I have a very basic question regarding to Puppet 3.0.1 configuration.

I setup a puppet master server (CentOS) with 2 agents (CentOS and Windows 7), all 3 can ping and access each other. There is no error at all.

I have copied a file under /etc/puppet/files/test2.txt

my /etc/puppet/manifests/site.pp contains these lines:

node default {
    file { "/tmp/testmaster.txt":
      owner => root,
      group => root,
      mode => 644,
      source => "puppet:///files/test2.txt"
    }
}

but there will no file be created on agent servers under /tmp/ once I run puppet agent --test

here is the output:

[root@agent1 ~]# puppet agent --test
Info: Retrieving plugin
Info: Caching catalog for agent1.mydomain.com
Info: Applying configuration version '1354267916'
Finished catalog run in 0.02 seconds

puppet apply /etc/puppet/manifests/site.pp creates the testmaster.txt under /tmp/ on master.