This presentation covers the basics of what container orchestration is providing pros and cons of Docker Swarm, Kubernetes and Amazon ECS and outlining the terms and tools you will need to successfully use them.

1. Container Orchestration
With Docker Swarm and Kubernetes
Will Hall
DevOps and Digital Architect

2. Container Orchestration
Orchestration probably exists to do two main things:
1. Resource Utilization
2. Scaling/healing

3. Provisioning, deployment and
integration between containers.

4. Orchestration Systems
There are a number of ways to do orchestration:
1. Kubernetes
2. Docker Swarm
3. Mesos
4. Nomad
5. Amazon ECS

5. Managing your platform as a cluster
You have a number of machines, they theoretically can act as 1 total machine (and you
add/remove nodes as the workload determines).

6. Kubernetes
Pros:
● Large, healthy ecosystem
● PaaS provided by GCP, Amazon, Azure, DigitalOcean
● Future of software delivery??
Cons:
● Complex management
● New tooling

7. Docker Swarm
Pros:
● Simple setup
● Simpler management (than Kubernetes)
Cons:
● No PaaS (Docker Enterprise?)
● Scale issues
● Vendor support

8. Amazon ECS
Pros:
● PaaS
● Integration with Amazon toolsets
Cons:
● Vendor lock-in
● Limited community support

9. Here is where I hit you
with an orchestration
dictionary

10. Docker Swarm

11. Docker Swarm Terms: Swarm and Service
Swarm. Like a cluster in Kubernetes, a swarm is a set of nodes with at least one master
node and several worker nodes that can be virtual or physical machines.
Service. A service is the tasks a manager or agent nodes must perform on the swarm, as
defined by a swarm administrator. A service defines which container images the swarm
should use and which commands the swarm will run in each container. A service in this
context is analogous to a microservice; for example, it’s where you’d define
configuration parameters for an nginx web server running in your swarm. You also
define parameters for replicas in the service definition.

12. Docker Swarm Terms: Manager, Worker and
Task
Manager node. When you deploy an application into a swarm, the manager node provides several functions: it
delivers work (in the form of tasks) to worker nodes, and it also manages the state of the swarm to which it
belongs. The manager node can run the same services worker nodes do, but you can also configure them to only
run manager node-related services.
Worker nodes. These nodes run tasks distributed by the manager node in the swarm. Each worker node runs an
agent that reports back to the master node about the state of the tasks assigned to it, so the manager node can
keep track of services and tasks running in the swarm.
Task. Tasks are Docker containers that execute the commands you defined in the service. Manager nodes assign
tasks to worker nodes, and after this assignment, the task cannot be moved to another worker. If the task fails in
a replica set, the manager will assign a new version of that task to another available node in the swarm.

13. Docker Swarm Tools: Docker/Docker
Compose
If you can use Docker and Docker Compose, you can deploy and manage things inside
Docker Swarm. It is the same toolset!

14. Let’s play
You can come back and look at these some other time.
https://play-with-docker.com

15. Kubernetes

16. Kubernetes Terms: Master and Kubelet
Kubernetes master. The master manages the scheduling and deployment of
application instances across nodes, and the full set of services the master node runs is
known as the control plane. The master communicates with nodes through the
Kubernetes API server. The scheduler assigns nodes to pods (one or more containers)
depending on the resource and policy constraints you’ve defined.
Kubelet. Each Kubernetes node runs an agent process called a kubelet that’s
responsible for managing the state of the node: starting, stopping, and maintaining
application containers based on instructions from the control plane. A kubelet receives
all of its information from the Kubernetes API server.

17. Kubernetes Terms: Pods and Deployments...
Pods. The basic scheduling unit, which consists of one or more containers guaranteed
to be co-located on the host machine and able to share resources. Each pod is assigned
a unique IP address within the cluster, allowing the application to use ports without
conflict. You describe the desired state of the containers in a pod through a YAML or
JSON object called a PodSpec. These objects are passed to the kubelet through the API
server
Deployments, replicas, and ReplicaSets. A deployment is a YAML object that defines
the pods and the number of container instances, called replicas, for each pod. You
define the number of replicas you want to have running in the cluster via a ReplicaSet,
which is part of the deployment object.

18. Kubernetes Tools: kubeadm/kubectl
You use kubeadm to administer your Kubernetes cluster
You can use kubectl to deploy applications, inspect and manage cluster resources, and
view logs.

19. Kubernetes Tools: Networking
Networking is a central part of Kubernetes, but it can be challenging to understand
exactly how it is expected to work. There are 4 distinct networking problems to
address:
1. Highly-coupled container-to-container communications
2. Pod-to-Pod communications
3. Pod-to-Service communications
4. External-to-Service communications

20. Kubernetes Tools: Helm
Helm helps you manage Kubernetes applications — Helm Charts help you define,
install, and upgrade even the most complex Kubernetes application.
Helm Charts are easy to create, version, share, and publish — so start using Helm and
stop the copy-and-paste.

21. Let’s play
You can come back and look at these some other time.
https://play-with-k8s.com

22. Takeaways
● Orchestration is both efficient and cost-saving
● It can deliver significant scaling and healing potential
● Choose the right solution for your problem