CentOS7 is OSS of RHEL7. But we had problems RDO Icehouse OpenStack install with packstack.
This behavior is due to the version notation was introduced in CentOS7 called "7.0.1406". So far, in CentOS7, and we use the notation such as "6.5" treated as values in the decimal point, it was also similar even RHEL.
String introduced in CentOS7 called "7.0.1406" can not be treated as a number.
Confuse itself caused the puppet upstream community that said version number is difficult to make out CentOS7 development community.