Install puppet to the XenServer

1. In file /etc/yum.repos.d/CentOS-Base.repo in section [base] set enabled=1

sed -i 's/enabled=0/enabled=1/g' /etc/yum.repos.d/CentOS-Base.repo

2. For XenServer 6.2, 6.5 in file /etc/yum.repos.d/Citrix.repo in section [citrix] set enabled=0

sed -i 's/enabled=1/enabled=0/g' /etc/yum.repos.d/Citrix.repo

3.  rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/$(uname -i)/epel-release-5-4.noarch.rpm
    cd /tmp
    wget https://yum.puppetlabs.com/el/5/products/$(uname -i)/puppetlabs-release-5-10.noarch.rpm
    rpm -Uvh puppetlabs-release-5-10.noarch.rpm
    yum install puppet
   

   set up /etc/puppet/puppet.conf, after that:

    chkconfig puppet on
    /etc/init.d/puppet start
   

I Also recommend using a xs_patcher to make XenServer up to date.