Docker Swarm vs. Kubernetes

Docker Swarm

Docker Swarm is a native Docker clustering tool that converts a collection of Docker servers into a single virtual host with a management and worker nodes. It helps with application deployment, scalability, service discovery, and load balancing across several hosts, easing container administration operations.

Docker Swarm Architecture

• Manager Nodes: Manage orchestration, clusters, and task distribution.
• API: accepts CLI commands and generates service objects.
• Orchestrator: Handles service object reconciliation and task creation.
• Scheduler: Assigns nodes to tasks according to resource availability.
• Dispatcher: Supervises worker nodes to ensure task completion.
• Worker Nodes: Execute containers and complete given tasks.
• Tasks: Tasks are individual containers maintained by the Swarm.
• Service: A collection of containers that share configurations using Docker's Swarm mode.

Docker Swarm Advantages

• Docker Swarm is simple to set up, making it perfect for beginners in container orchestration.
• Lightweight, with automated load balancing within containers.
• Integrates seamlessly with the Docker CLI and existing Docker tools such as Docker Compose.
• Enables intelligent node selection for optimal container deployment.
• Provides its own Swarm API for management.

Docker Swarm Disadvantages

• Scalability is limited when compared to other orchestration technologies.
• Less feature-rich than Kubernetes.
• Less community and ecosystem support.
• A lack of advanced networking functions.
• There is limited support for complex deployment situations.

Docker Swarm vs. Kubernetes

• Installation: Kubernetes is simpler than Docker Swarm.
• GUI Support: Kubernetes has a built-in Web UI, whereas Docker Swarm requires additional configuration for GUI support.
• Cluster Configuration: Kubernetes requires manual setup and planning, but Docker Swarm is simpler and allows for post-configuration node addition.
• API Functionality: Unlike Docker Swarm, which relies on Docker's standards, Kubernetes creates its own API and YAML specifications.
• Scalability: Kubernetes expands quickly in large clusters, whereas Docker Swarm focuses on robust cluster state guarantees.
• High Availability: Unlike Docker Swarm, which relies on manager nodes, Kubernetes offers several master nodes for availability.