Network Access

1. Overview

This document specifies network and port requirements for Kublr and Kublr-managed Kubernetes deployment.

2. General Approach

Each Kubernetes cluster (including the cluster on which the Kublr Control Plane is running) requires IP netwrok connectivity between all of its nodes - master and workers. The open ports may be limited by a firewall, but all master and worker nodes must be able to reach each other on their IP addresses.

IP connectivity between nodes in different clusters is generally not required, different clusters may use different subnets, even if their IP spaces intersect.

Additionally Kublr Control Plane (KCP) must be able to access at least one API endpoint of each managed cluster, as well as be able to access infrastructure (e.g. cloud) provider API, and in case of on-prem deployment - cluster master nodes.

3. Port Requirements

Kublr and Kubernetes components communicate with each other using ports. The following ports required by Kublr and Kubernetes must be open between hosts, for example if you have a firewall in your environment. Some ports are optional depending on your configuration and usage.

In the following tables term “Node” is used as a generalization of “Master and/or Worker node”.

Table 1. Node to Node (masters and workers)

Table 2. Workers to Masters

Table 3. Master to Masters

Table 4. Other

Table 5. Kublr Control Plane