Air-Gap Infrastructure Services for Kubernetes Offline Deployment

Overview

Air-gap Kubernetes deployment requires several infrastructure services running on the admin server before cluster deployment can begin. These services replace what would normally be provided by the internet: DNS resolution, time synchronization, network routing, package repositories, and Python package mirrors.

Core principle: The admin server acts as the central hub providing all network services to the isolated internal network. Every node in the cluster depends on the admin server for name resolution, time sync, package installation, and container image pulls.

When to Use

• Setting up a DNS server (bind) for name resolution in isolated networks
• Configuring NTP time synchronization (chrony) in air-gap environments
• Creating a NAT gateway for controlled or temporary internet access
• Building local YUM/DNF package mirrors via reposync
• Setting up a PyPI mirror (devpi or pypi-mirror) for Python packages
• Preparing the admin server before running kubespray-offline

Network Architecture