In addition to functional considerations, commercial core networks must also consider scalability and availability. If the core network encounters a single node or network function failure during the serving period, it must overcome the software or hardware problems and maintain a stable service. For fifth-generation (5G) and beyond core networks, network function virtualization enables scalability and flexibility for deployment, and 5G and beyond core network design follows the concept of service-oriented architecture, similar to cloud-native microservice architecture; hence, the deployment of core networks using a cloud-native solution (e.g., Kubernetes) is possible. To achieve high availability (HA) for cloud-native-based core networks, we design GO-CPSV, a generic HA solution based on the open-source OpenSAF project. GO-CPSV introduces new elements to enhance the affinity with cloud-native deployment, including life-cycle hooks, concurrent enhancement, and multiple storage providers. We then implement HA-UDR based on the Unified Data Repository (UDR) network function of the open-source free5GC core network to validate our design.