Submariner

• Architecture
• Network Path
• Prerequisites
• Installation
• Installation using subctl
• Installation using Helm
• Validate Submariner is Working
• Building and Testing
• Known Issues
• Contributing

Submariner is a tool built to connect overlay networks of different Kubernetes clusters. Submariner is designed to be network plugin (CNI) agnostic and supports both encrypted and non-encrypted tunnels between the connected clusters.

Note that Submariner is in an early stage, and while we welcome usage and experimentation, it is quite possible that you could run into bugs.

Submariner is a Cloud Native Computing Foundation sandbox project.

Architecture

See the Architecture section of Submariner's website.

Network Path

The network path of Submariner varies depending on the origin/destination of the IP traffic. In all cases, traffic between two clusters will transit between the leader elected (in each cluster) gateway nodes, through the configured cable driver.

When the source Pod is on a worker node that is not the elected gateway node, the traffic destined for the remote cluster will transit through the submariner VXLAN tunnel (vx-submariner) to the local cluster gateway node. On the gateway node, traffic is forwarded to the remote cluster over the configured tunnel. Once the traffic reaches the destination gateway node, it is routed in one of two ways, depending on the destination CIDR. If the destination CIDR is a Pod network, the traffic is routed via CNI-programmed network. If the destination CIDR is a Service network, then traffic is routed through the facility configured via kube-proxy on the destination gateway node.

Prerequisites

See the Prerequisites docs on Submariner's website.

Installation

Submariner is always deployed using a Go-based Kubernetes custom controller, called an Operator, that provides API-based installation and management. Deployment tools like the subctl command line utility and Helm charts wrap the Operator. The recommended deployment method is subctl, as it is currently the default in CI and provides diagnostic features.

See the Deplyment docs on Submariner's website.

Installation using subctl

Submariner provides the subctl CLI utility to simplify the deployment and maintenance of Submariner across your clusters.

See the subctl Deployment docs on Submariner's website.

Installation using Helm

See the Helm Deployment docs on Submariner's website.

Validate Submariner is Working

See the subctl verify docs and Automated Troubleshooting docs on Submariner's website.

Building and Testing

See the Building and Testing docs on Submariner's website.

Known Issues

See the Known Issues docs on Submariner's website.

Contributing

See the Development section of Submariner's website.