84 Red Hat OpenShift and IBM Cloud Paks on IBM Power Systems: Volume 1
PowerVC supports the following policies:
/SM590000Affinity: All virtual machines from this rule are hosted on the same host.
/SM590000Anti-affinity: All virtual machines from this rule are hosted on different host.
/SM590000Soft-affinity: All virtual machines from this rule are hosted on the same host if possible; if 
not possible, they still are scheduled instead of failure and set the status of the rule to 
violated.
/SM590000Soft-anti-affinity: All virtual machines from this rule are hosted on different host, if possible; 
if not possible, they still are scheduled instead of failure and set the status of the rule to 
violated.
If the rule status is violated, review the placement of the virtual machines. For any virtual 
machines that are on an incorrect host, you can migrate it to the correct host by using LPM.
PowerVC image
A custom image must be created in PowerVC before the deployment is started. OpenShift 
includes the following specific requirements:
/SM590000RHEL 7.6 for POWER8 and RHEL-ALT 7.6 for POWER9 Minimum installation.
/SM590000SELinux is set to enforcing.
/SM590000NetworkManager is enabled and running.
/SM590000Firewall is enabled and running.
/SM590000The host name from DNS (set_hostname_from_dns) is set in cloud-init.
Project and user
A project, sometimes referred to as a tenant, is a unit of ownership. Most resources, such as 
virtual machines, volumes, and images, belong to a specific project. Only users with a role 
assignment for a specific project can work with the resources that belong to that project. The 
ibm-default project is created during installation, but PowerVC supports the creation of more 
projects for resource segregation.
When possible, it is recommended to create a user and project for the OpenShift 
environment.
High Availability
High Availability (HA) is a requirement for any production deployment. A crucial consideration 
for HA is the removal of single points of failure (SPOFs). This reference architecture is highly 
available at all layers (Hardware, PowerVM, PowerVC, and OpenShift).
Hardware HA
You must take care to eliminate single points of failure at the hardware layer. The following 
hardware fault tolerance recommendations are implemented in this architecture:
/SM590000Redundant server power supplies that are connected to different power sources.
/SM590000Redundant network adapters that are connected to redundant network switches.
/SM590000Redundant Fibre Channel adapters that are connected to redundant SAN fabrics.
Note: For more information about image creation in PowerVC, see IBM Knowledge Center.