classicswarm
Swarm Classic: a container clustering system. Not to be confused with Docker Swarm which is at https://github.com/docker/swarmkit
Classic Swarm was Docker's original tool for managing multiple servers as one, letting you run containers across a pool of machines with a single Docker command. It is now archived and replaced by Docker's built-in Swarm mode.
Classic Swarm was Docker's first tool for managing a group of servers running Docker containers as if they were a single machine. Instead of connecting to each server separately, you would point your Docker commands at Swarm, and it would figure out which server in the pool to run each container on. The project started in 2014 and was Docker's earliest attempt at what is called container orchestration, meaning coordinating workloads across multiple machines.
This repository is archived and no longer maintained. Docker built a newer, more capable version of this functionality directly into the Docker Engine itself, called Swarm mode (sometimes referred to as Swarmkit). The newer built-in version handles things like automatic restarts, load balancing, and service discovery, which Classic Swarm did not support. Anyone still looking at this project is directed to use Docker's built-in Swarm mode or a different orchestration system entirely.
The README is short because the project is no longer active. The code is written in Go and was released under the Apache 2.0 license. It represents a historical step in how Docker evolved before more sophisticated orchestration tools became standard.
Where it fits
- Study how early container orchestration worked before Kubernetes and modern Docker Swarm became standard
- Understand Docker's architectural history when researching container technology evolution
- Reference legacy Classic Swarm configs when migrating old infrastructure to Docker Swarm mode or Kubernetes