Container Orchestration


- Native cluster management and orchestration for Docker
- A pool of Docker hosts to a single, virtual Docker host
- Docker Swarm serves the standard Docker API
- Standalone Swarm before Docker version 1.12
- In Docker 1.12 and higher, Swarm Mode integrated with Docker Engine
- Integrated cluster management with Docker engine
- Declarative service model with YAML based files
- Scaling with declaring the number of tasks
- Make sure apps are up and running with Desired state reconciliation
- Managed Multi-host networking
- Service discovery with unique DNS names
- Load balancing
- Secure by default with TLS mutual authentication and encryption for communications
- Rolling updates for delaying deployments and rollback
- Nodes: An instance of the Docker engine participating in the swarm
- Manager: Performs the orchestration and cluster management. Dispatches unit of works to worker nodes.
- Worker: Receives and executes tasks dispatched from manager nodes
- Task: Atomic scheduling unit of swarm. A running container which is part of a swarm service and managed by a swarm manager, as opposed to a standalone container
- Service: The definition of the tasks to execute on swarm cluster. Replicated Services and Global Services
- Stack: The definition of the services to execute on swarm cluster
- Load Balancing: Swarm manager uses ingress load balancing to expose the services via PublishedPort
- docker-compose -f docker-compose.yml up -d
- docker stack deploy -c docker-compose.yml stack_name
- Docker stack is ignoring “build” instructions.
- Docker compose is a Python project. Origin is “fig”. You should install docker-compose separately to use it.
- Docker Stack is included with the Docker Engine from version 1.12
- To use Docker Stack, Swarm mode should be enabled
- Docker Stack not supporting docker-compose files which are written according to Version 2 specification. Docker Compose supports Version 2 and 3

- maintaining cluster state
- scheduling services
- serving swarm mode HTTP API endpoints
- To deploy an application image in swarm mode, we must create a service.
- When we create a service, we specify some options;
- Image name
- Commands
- Port
- Networking
- Resources
- Rolling update policy
- Replica count


0 Comments
Share