I am receiving the following error on a Puppet agent when trying to install multiple packages at once:

err: /Stage[main]/Template::Infrastructure/Package[undef]/ensure: change from absent to present failed: Execution of '/usr/bin/yum -d 0 -e 0 -y install undef' returned 1: Error: Nothing to do

The code generating the error is:

$packages = [ 'qemu-kvm', 'qemu-kvm-tools', 'drbd84-tools', 'kmod-drbd84' ]
package {
  $::packages :
    ensure  =>  'installed',
    require =>  Class['yumrepos::elrepo']
}

The problem is intermittent. Is there a better way to install multiple packages at once without having to setup a package resource for each?