I did not yet implemented GPG Key.

  [K2 - Perl]
  name=K2 - Perl
  baseurl=http://108.35.22.7:1111/centos/$releasever/perl/$basearch/
  enabled=1
  gpgcheck=0
 
  [K2 - Update]
  name=K2 - Update
  baseurl=http://108.35.22.7:1111/centos/$releasever/updates/$basearch/
  enabled=1
  gpgcheck=0

use following centOS dev wiki

  [c5-testing]
  name=CentOS-5 Testing
  baseurl=http://dev.centos.org/centos/$releasever/testing/$basearch/
  enabled=1
  gpgcheck=1
  gpgkey=http://dev.centos.org/centos/RPM-GPG-KEY-CentOS-testing
  includepkgs=php*

Kickstart

list all installed GPG Key

rpm -q gpg-pubkey --qf '%{name}-%{version}-%{release} --> %{summary}\n'

Remove unnecessary keys from yum / rpm

rpm -e gpg-pubkey-443e1821-421f218f gpg-pubkey-a3901351-4e1b6312

How to limit packages and setup priority on exclude include packages.

[Atomi-OSSEC]
name=OSSEC
baseurl=http://www6.atomicorp.com/channels/atomic/centos/5EL/x86_64/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-OSSEC
includepkgs=ossec*,mysql*
excludepkgs=*
includepkgorder=includepkg,excludepkg