Submariner: Cross-Cluster Networking for Kubernetes
Shriira Press
Submariner connects Kubernetes clusters into a single flat network — direct Pod and Service communication, with DNS-based discovery, across clouds and data centers.
Welcome to Submariner: Cross-Cluster Networking for Kubernetes.
Submariner is a Cloud Native Computing Foundation sandbox project that solves a deceptively hard problem: making separate Kubernetes clusters talk to each other directly, as if their Pods and Services shared one network. A single cluster gives every Pod an IP and lets any Pod reach any Service by name, but that magic stops at the cluster boundary — two clusters, whether across a data center or across clouds, normally cannot reach each other's internal addresses at all. Submariner flattens that boundary. This book walks the whole system from the ground up. It opens with the multi-cluster problem and the idea of a clusterset, then builds the architecture piece by piece: the Broker that coordinates clusters, the Gateway Engine that runs the encrypted tunnels, the Route Agent that wires every node into the fabric, and Lighthouse, which carries Kubernetes service discovery across cluster lines. From there it covers Globalnet for the common headache of overlapping IP ranges, the subctl command-line tool you actually deploy with, and a closing chapter on running Submariner well in production.
This title is part of the ShriIra library and is free to read in full, right here — our small contribution to making world-class knowledge easy to reach.
A note on reading it: open the Contents menu at the top of the reader to jump between chapters, use the Aa menu to set a comfortable text size, theme (light, sepia, or night), and single- or two-page layout. Your place is saved automatically, so you can always pick up where you left off.
We hope it serves you well.
— Shriira Press