1. Testing Is a Beacon at Sea The more complex and larger a project is, the more it demonstrates the value and importance of testing. Testing guarantees that the direction is right. Like a beacon appearing at sea while sailing, it can be used to check and correct the course, so the helmsman can stay aware of the situation at any moment and make adjustments.

1. On the Aesthetics of CICD Tools In the document A Software Product Is the Output of a Team’s Capability, I mentioned that a software product is the delivery vehicle for a solution, and that its quality depends on the team’s understanding of the core problem. Only with a deep understanding of the domain can the delivered product have a chance of being good.

1. daemon-less Image Build Tools 1.1 What Is a daemon-less Image Build Tool In a CICD pipeline, image builds come up often, and the conventional approach is to build with Docker in Docker or Docker out of Docker. For details, see: How to Use Docker in Docker In fact, to avoid monopolies and advance the industry, a unified OCI image format specification based on the Docker image format was defined long ago.

1. Typical Use Cases In CI, there is usually a CI Engine responsible for parsing the pipeline and controlling the whole build process, while the actual build is delegated to an Agent. Jenkins and GitLab both work this way. As shown below, there are many kinds of Agents that connect to the CI Engine.

Kubernetes relies on the kube-proxy component to implement Service communication and load balancing. In this process, because SNAT is used to translate the source address, a service in a Pod cannot obtain the real client IP address. This article mainly answers the question of how a workload in a Kubernetes cluster can obtain the real IP address of the client.