About the Prerequisite Operators

The Openshift NMState Operator acts as a configuration engine for NetworkManager. Nmstate simplifies network configuration tasks by providing a declarative API for managing network settings, allowing users to define network setups using YAML or JSON. It supports physical servers deployed with OpenShift and virtualized environments, enabling the creation of bonds, bridges, VLAN interfaces, and more through encapsulated configurations. These configurations can be combined into single files for consistent setups across nodes. We will be utilizing this operator for configuration of OpenStack network isolation on the nodes.

MetalLB is a load balancer solution for Kubernetes clusters. In the current use case of OSP services deployment on OCP cluster, the MetalLB operator manages the deployment via CRDs, like IPAddressPool and L2Advertisement. This implementation of MetalLB operates in layer2 mode. It requires IP address pools for load balancer services, configurable via IPAddressPool CR. L2Advertisement CR facilitates IP advertisement from specified pools, ensuring efficient IP allocation to services and namespaces.

The cert-manager Operator for Red Hat OpenShift is a cluster-wide service that provides application certificate lifecycle management. It allows you to integrate with external certificate authorities and provides certificate provisioning, renewal, and retirement.