The very first time that I install a package from epel, I am prompted if I want to import a GPG key. Notice how there are 2 'Is this ok' prompts when installing redis? [root@us-devops-build02 yum.repos.d]# yum install redisLoaded plugins: fastestmirrorLoading mirror speeds from cached hostfile.. truncated for readabilityTotal download size: 213 kInstalled size: 668 kIs this ok [y/N]: yDownloading Packages:redis-2.4.10-1.el6.x86_64.rpm                                                                                                                                                                                                                                                                          | 213 kB     00:00     warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID 0608b895: NOKEYRetrieving key from http://download.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-6Importing GPG key 0x0608B895: Userid: EPEL (6) <epel@fedoraproject.org> From  : http://download.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-6Is this ok [y/N]: yThis causes puppet to fail on freshly-provisioned machines, unless I ssh in to the machine first and manually accept the installation of this key. Why does epel need a key to be downloaded on the first installation of a package? How can I automatically install this key on my images so puppet won't fail? 
How to automatically accept epel gpg key
package management;rpm;gpg
The reason yum is asking for a key is that it is not present in /etc/pki/rpm-gpgls /etc/pki/rpm-gpg/ | columnRPM-GPG-KEY-CentOS-6        RPM-GPG-KEY-CentOS-Security-6    RPM-GPG-KEY-CentOS-Debug-6RPM-GPG-KEY-CentOS-Testing-6    RPM-GPG-KEY-puppetlabsYou can import the key in one of 4 ways: use rpm --import http://download.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-6 (as suggested by slm)Install a package and then wait for the prompt (like I was doing)Use the RPM package provided by epel, it installs the repo and the key simultaneously. sudo yum -y install http://mirror.pnl.gov/epel/6/i386/epel-release-6-8.noarch.rpmManually copy the key to the right directory. 