What is Harbor?

Harbor is an open-source container image registry that stores, scans, and manages Docker images and Helm charts. It adds security features like vulnerability scanning and role-based access control on top of a basic image storage service.

Let's break it down

  • Open-source: Free to use and its code can be viewed or modified by anyone.
  • Container image registry: A place (like a library) where ready-made software packages called container images are kept.
  • Docker images: Packaged applications that run inside containers.
  • Helm charts: Pre-written templates that help install applications on Kubernetes.
  • Vulnerability scanning: Automatic checks that look for known security problems in the images.
  • Role-based access control (RBAC): Rules that decide who can view, upload, or delete images.

Why does it matter?

Harbor helps teams keep their container images safe, organized, and easy to share, which reduces the risk of security breaches and speeds up development and deployment cycles.

Where is it used?

  • In CI/CD pipelines to store built images before they are deployed to production.
  • As the central registry for Kubernetes clusters in large enterprises, enabling multi-team collaboration.
  • In edge-computing environments where images need to be replicated across distant locations.
  • For regulated industries (e.g., finance, healthcare) that require audit trails and strict access controls on software artifacts.

Good things about it

  • Built-in vulnerability scanning and image signing for security.
  • Fine-grained RBAC lets administrators control who can do what.
  • Supports replication to other registries, enabling multi-site deployments.
  • Friendly web UI plus full API for automation.
  • Works with existing Docker registry APIs, so tools that already use Docker Hub can switch to Harbor easily.

Not-so-good things

  • Adds extra infrastructure (database, storage, and a web server) that must be maintained.
  • Initial setup and configuration can be complex for beginners.
  • Performance may lag behind lightweight registries when handling very high upload/download volumes.
  • Some advanced security features (e.g., content trust) require additional components or licensing.