Harbor

Harbor helps bring assurance to container images and other cloud-native artifacts by providing a robust, feature-rich registry solution. At its core, Harbor extends the Docker Distribution with additional functionalities such as security, identity, and management, making it a trusted cloud-native registry.

The technical architecture of Harbor is designed to be highly scalable and flexible. It supports both container images and Helm charts, and integrates with various cloud-native environments, including container runtimes and orchestration platforms like Kubernetes. Harbor's architecture includes components such as the Core, Registry, Registry Controller, Job Service, and Portal, which can be deployed in minimal or standard stacks depending on the requirements. The Harbor Operator further simplifies the deployment and management of Harbor by defining custom resources on top of Kubernetes, ensuring scalability and high availability.

Key operational considerations include the use of role-based access control, where users access repositories through projects with defined permissions. Policy-based replication allows for the synchronization of images and charts between multiple registry instances, enhancing load balancing and high availability. Harbor also features vulnerability scanning, LDAP/AD integration, and OIDC support for user authentication. The system includes automated garbage collection for image deletion and supports Docker Content Trust for image signing and provenance.

From a technical standpoint, Harbor provides RESTful APIs for administrative operations and integration with external systems. It can be deployed using Docker Compose, Helm Charts, or the Harbor Operator. The system requires specific versions of Docker and Docker Compose for installation and supports various deployment scenarios, including those behind proxies and load balancers.

However, there are operational limitations to consider. For instance, the main branch of Harbor may be unstable during development, and users are advised to use stable releases. Additionally, the Harbor CLI, while powerful, may not support all functionalities in versions prior to 2.11. Overall, Harbor's comprehensive feature set and flexible deployment options make it a powerful tool for managing cloud-native registries, but it requires careful planning and configuration to fully leverage its capabilities.