The document outlines the use of Kubernetes for orchestrating microservices, highlighting concepts such as pods, deployments, and services, and explaining how they interact within a cluster. It also discusses the architecture of Kubernetes, the use of container images, and service discovery methods, including ClusterIP and NodePort. Additionally, it emphasizes the importance of continuous delivery and monitoring in enhancing developer experience with microservices.

1. Orchestrating Microservices
with Kubernetes
Jeff Hoffer, Developer Experience
github.com/eudaimos

2. What does Weave do?
Weave helps devops
iterate faster with:
• observability &
monitoring
• continuous delivery
• container networks
& firewalls
Kubernetes is our #1
platform

3. Agenda
1. Concepts
2. Containers, Pods, Deployments, Services
3. Installing Kubernetes
4. Demos of Pods, Deployments, Services
5. Microservices sample app
6. What’s next?

4. Kubernetes: all you need to know
Pods
containers
Services
Deployments

5. Concepts
Computer

6. Concepts
Node

7. Concepts
nginx Container
image: nginx:1.7.9
Node

8. web
Concepts
nginx Container
Pod
logger
Node

9. web
Concepts
nginx Container
Pod
logger
IP addr
Node

10. web
Concepts
Podnginx
apiVersion: v1
kind: Pod
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
Node

11. Recap: all you need to know
Pods
containers
Container
Image
Docker container image, contains your application code in an isolated
environment.
Pod A set of containers, sharing network namespace and local volumes,
co-scheduled on one machine. Mortal. Has pod IP. Has labels.

12. Motivation for Deployments
Node 1
Pod
web
nginx
Node 2

13. Motivation for Deployments
Pod
web
nginx
Node 1 Node 2

14. Motivation for Deployments
Pod
web
nginx
Node 1 Node 2

15. Deployment
web
nginx
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 1
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
Node 1

16. Deployment
web
nginx
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 1
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
Node 1

17. Deployment
web
nginx
Node 1 Node 2

18. Deployment
web
nginx
Node 1 Node 2

19. Deployment
web
nginx
Node 1 Node 2

20. Deployment
web
nginx
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 1
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
Node 1

21. Deployment
web
nginx
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
Node 1

22. Deployment
web
nginx
web
nginx
Node 1 Node 2

23. Recap: all you need to know
Pods
containers
Deployments
Container
Image
Docker container image, contains your application code in an isolated
environment.
Pod A set of containers, sharing network namespace and local volumes,
co-scheduled on one machine. Mortal. Has pod IP. Has labels.
Deployment Specify how many replicas of a pod should run in a cluster. Then
ensures that many are running across the cluster.

24. Service discovery
• Kubernetes provides DNS for service
discovery

25. Service discovery
• Kubernetes provides DNS for service
discovery
WAIT! You said “service”.
What is a service?

26. Services: ClusterIP (internal things)
Computer 1
web
ruby
Computer 2
10.0.0.1
db
pgsql
10.0.0.2
service VIP
10.1.0.1DNS lookup “db”
returns A 10.1.0.1

27. Services: ClusterIP (internal things)
Computer 1
web
ruby
Computer 2
10.0.0.1
db
pgsql
10.0.0.2
service VIP
10.1.0.1

28. Services: NodePort (external)
Computer 1
web
nginx
web
nginx
10.0.0.1 10.0.0.2
81.23.64.18 81.23.64.19
requests requests
Computer 2

29. Computer 1
web
nginx
web
nginx
10.0.0.1 10.0.0.2
81.23.64.18 81.23.64.19
requests requests
Computer 2
Services: NodePort (external)
NodePort 30001
service VIP
10.1.0.1
NodePort 30001
service VIP
10.1.0.1

30. Computer 1
web
nginx
web
nginx
10.0.0.1 10.0.0.2
81.23.64.18 81.23.64.19
requests requests
Computer 2
Services: NodePort (external)
NodePort 30001
service VIP
10.1.0.1
NodePort 30001
service VIP
10.1.0.1

31. kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
kind: Service
metadata:
name: frontend
spec:
type: NodePort
selector:
app: nginx
ports:
- port: 80
targetPort: 80
nodePort: 30002
Using selectors
How do services connect to deployments?
matches

32. kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
kind: Service
metadata:
name: frontend
spec:
type: NodePort
selector:
app: nginx
ports:
- port: 80
targetPort: 80
nodePort: 30002
How do you expose services to outside?
Using NodePort

33. Recap: all you need to know
Pods
containers
ServicesDeployments
Container
Image
Docker container image, contains your application code in an isolated
environment.
Pod A set of containers, sharing network namespace and local volumes,
co-scheduled on one machine. Mortal. Has pod IP. Has labels.
Deployment Specify how many replicas of a pod should run in a cluster. Then
ensures that many are running across the cluster. Has labels.
Service Names things in DNS. Gets virtual IP. Two types: ClusterIP for internal
services, NodePort for publishing to outside. Routes based on labels.

34. Architecture of Kubernetes itself
Node 1 Node 2
Master

35. API server
Architecture of Kubernetes itself
Node 1 Node 2
Master
API server etcd
kubeadm init

36. API server
Architecture of Kubernetes itself
Node 1 Node 2
Master
API server etcd
kubeadm init
kubeadm join
kubelet

37. API server
Architecture of Kubernetes itself
Node 1 Node 2
Master
API server etcd
kubeadm init
kubeadm join kubeadm join
kubelet kubelet

38. API server
Architecture of Kubernetes itself
Node 1 Node 2
Master
API server etcd
kubeadm init
kubeadm join kubeadm join
kubelet kubelet
kubectl apply

39. API server
Architecture of Kubernetes itself
Node 1 Node 2
Master
containers
Services
containers
API server etcd
kubeadm init
kubeadm join kubeadm join
kubectl apply
kubelet kubelet

40. Training!

41. Join the Weave user group!
meetup.com/pro/Weave/
weave.works/help

42. What’s next?
• Continuous delivery: hooking up my CI/CD
pipeline to Kubernetes
• How do I monitor this stuff?
• Network policy for security
Come to our Weave Cloud training to find out!

43. Thanks! Questions?
We are hiring!
DX in San Francisco
Engineers in London & SF
weave.works/weave-company/hiring