anchor.diff:  a|- Physical or virtual system, or an instance running on a public or private IaaS.
   ifdef::openshift-origin[]
   - Base OS: Fedora 21, CentOS 7.1, or RHEL 7.1 or later with "Minimal"
  -installation option, or RHEL Atomic Host 7.2.3 or later.
  +installation option, or RHEL Atomic Host 7.2.4 or later.
   endif::[]
   ifdef::openshift-enterprise[]
   - Base OS: RHEL 7.1 or later with "Minimal" installation option, or RHEL Atomic
  -Host 7.2.3 or later.
  +Host 7.2.4 or later.
   endif::[]
   - 2 vCPU.
   - Minimum 8 GB RAM.
  
positive.code: 
  *Installing an Operating System*
  
  A base installation of RHEL 7.1 or later or RHEL Atomic Host 7.2.3 or later is
  required for master and node hosts. See the following documentation for the
  respective installation instructions, if required:
  
  
negative.code: a| - Physical or virtual system, or an instance running on a public or private IaaS.
  ifdef::openshift-origin[]
  - Base OS: Fedora 21, CentOS 7.1, or RHEL 7.1 or later with "Minimal"
  installation option, or RHEL Atomic Host 7.2.4 or later.
  endif::[]
  ifdef::openshift-enterprise[]
  - Base OS: RHEL 7.1 or later with "Minimal" installation option, or RHEL Atomic
  Host 7.2.4 or later.
  endif::[]
  - 1 vCPU.
  - Minimum 8 GB RAM.
  