Running Tailscale in a Container

2026-01-25

Introduction

Containerizing Tailscale provides a clean, isolated way to connect your devices into a secure, private network without installing dependencies directly on your host system. Whether you're running Tailscale on a single server, orchestrating containerized applications across a cluster, or securing access to internal services, a containerized approach offers reproducibility, ease of deployment, and straightforward updates.

The primary use case explored here is leveraging Tailscale in a container to establish secure, encrypted connections between your devices and services, ensuring your traffic remains private and protected from external access across untrusted networks.

What is Tailscale?

Tailscale enables you to build your own private network by interconnecting multiple computers, users, and services into a unified system. This personal network remains hidden from the broader internet, accessible only to those you explicitly authorize. Think of it as having your own private communication backbone that spans across the globe, connecting only the machines and services you control.

Under the hood, Tailscale uses WireGuard, a cutting-edge VPN protocol, to forge direct encrypted connections between devices in your network. Your devices are assigned private IP addresses that allow them to communicate securely with each other, regardless of where they're physically located or what networks they're connected to. This creates a unified, private address space that's yours alone.

Why Containerize Tailscale?

Running Tailscale in a Docker or Podman container provides several advantages:

Isolation: The Tailscale daemon runs in its own confined environment, kept separate from your main system and other running services, preventing unwanted interactions.
Reproducibility: The container guarantees identical behavior when deployed across different machines and operating systems.
Version control: You can easily pin specific Tailscale versions and maintain configuration files without touching your underlying system.
Clean namespace: Network setup and TUN device configuration remain contained within the container boundary.
Simple updates: Updating Tailscale becomes as simple as rebuilding your container image without disrupting your host or adjacent containers.
Portability: Deploy Tailscale identically whether you're developing locally, staging in a test environment, or running in production.

Network Architecture and Security

Tailscale builds encrypted tunnels between your devices using WireGuard, a modern VPN technology known for both strong security and high performance. Rather than routing all traffic through a single central point, Tailscale intelligently attempts to establish direct connections between machines whenever possible, relying on relay infrastructure only when peer-to-peer communication isn't feasible.

When running Tailscale in a container, you gain the ability to selectively route traffic through your private network, integrate containerized workloads with your secure infrastructure, and maintain isolation between the container and the underlying host. This becomes especially useful in microservices architectures where you need encrypted, authenticated communication between services without exposing them publicly.

Getting Started

I've created a ready-to-use, distroless Dockerfile and comprehensive documentation for running Tailscale in a container. The distroless approach minimizes the container image size and attack surface by including only the Tailscale binary and its runtime dependencies, without unnecessary utilities or shells.

The repository includes everything you need to build and run the container, along with examples of how to configure your applications to use the Tailscale network. Check out the full implementation on GitHub:

Tailscale Distroless Dockerfile and Documentation

The README offers detailed instructions for building the container image, authenticating with your tailnet, and running the container with the correct TUN device access and network settings.

Practical Applications

This setup is invaluable in several scenarios:

Securing access to services running in Kubernetes clusters across multiple cloud providers and on-premises infrastructure.
Building private, encrypted overlays for distributed applications and microservices.
Providing secure remote access to internal tools and databases without traditional VPN complexity.
Establishing site-to-site connectivity using subnet routers in containers.
Connecting development environments to production services securely without exposing them to the public internet.
Enabling secure collaboration with external partners and contractors through Tailscale's built-in sharing capabilities.
Testing network routing and failover behavior in isolated, containerized environments.

Conclusion

Containerizing Tailscale provides a powerful, flexible approach to building secure, private networks for your applications and infrastructure. By leveraging container technology for isolation and reproducibility, you gain fine-grained control over your network architecture while maintaining security and ease of deployment.

Whether you're a developer, system administrator, or infrastructure engineer, this technique is a valuable addition to your toolbox for securing communications in modern, containerized environments. The distroless approach ensures minimal overhead while maintaining maximum security and compatibility.

Fabian's Lines of Thought