1. SSH Connection direction: Master actively connects to Agent Requirements: Master can connect directly to Agent over SSH The SSHD service is running on Agent Jenkins has the SSH Credentials Plugin and the SSH Build Agents plugin installed 2. JNLP Connection direction: Agent actively connects to Master Requirements: Agent can reach Master Agent needs a JVM environment to run Master needs to expose port 50000 (the default) for Agent communication Port 50000 is the service port of the Jenkins Master; no other service program needs to be run for it.

1. About Two Places and Three Centers As shown above, the two-places-three-centers architecture exists to improve the fault tolerance and disaster recovery capability of a system. When one data center becomes unavailable, traffic for critical business can be switched to another data center, which makes the system resilient to city-level natural disasters.

1. Why We Need to Define the Application Runtime There are more runtime choices. Traditional application runtimes include physical machines, virtual machines, and cloud hosts. In the container era, the common runtimes are Docker and Kubernetes. These runtimes no longer present us with a single runtime choice. Application topologies are more complex.

Kubevela is currently at version 1.1. We usually consider 1.x releases to be relatively stable and safe to try in production. Through continuous tracking and learning, I have also come to appreciate some of the things Kubevela does well. This is a summary document. 1. What Problem Kubevela Solves Aimed at platform developers Several roles need to be distinguished: development, operations, and operations development.

1. Environment Preparation 1.1 Calico eBPF Requirements System requirements Ubuntu 18.04.4+ Red Hat v8.2 Linux kernel v5.3+ If Calico does not detect a compatible kernel, it falls back to standard mode. Every node needs a BPF filesystem mounted at /sys/fs/bpf Calico version no lower than 3.13 1.2 Upgrading the Kernel This uses CentOS 7: