My presentation on microservices at scale with docker and kubernetes for the Amsterdam Java User Group on 9-2-20117

1. Micro services at scale with Docker and
Kubernetes
9-2-2017 – Amsterdam JUG

2. Bedankt voor jullie aandacht
“Once you stop learning, you start dying”
- Albert Einstein
ARJEN WASSINK
Principal Consultant
a.wassink@quintor.nl
@ArjenWassink

3. The Menu
1. Intro Microservices
2. Intro Docker
3. Kubernetes
4. Rolling updates
5. Persisted volumes
6. Stateful services

4. 4 Raspberry Pi 2B
Quadcore 900MHz, 1GB RAM, 16GB SD-card
Pi Stack case
D-Link network switch
Anker USB power adapter
Nice white cables
Total Cost: +/- EUR 300

5. Martin Fowler on Microservices:
In short, the microservice architectural style [1] is an approach to
developing a single application as a suite of small services, each running
in its own process and communicating with lightweight mechanisms,
often an HTTP resource API. These services are built around business
capabilities and independently deployable by fully automated
deployment machinery. There is a bare minimum of centralized
management of these services, which may be written in different
programming languages and use different data storage technologies.

6. Microservices: Scaling is important
https://www.nginx.com/blog/introduction-to-microservices/

7. Microservices: advantages
● The services themselves are very simple, focussing on doing
one thing well;
● Each service can be built using the best and most appropriate
tool for the job;
● Systems built in this way are inherently loosely coupled;
● Multiple developers and teams can deliver relatively
independently of each other under this model;
● They are a great enabler for continuous delivery, allowing
frequent releases whilst keeping the rest of the system
available and stable.

8. Microservices: drawbacks
● Complex distributed systems
● Diverse technology stack
● More software projects to manage
● Reliability and performance
● Exponentially more service instances to manage

9. Build Ship Run

10. http://www.zdnet.com/article/what-is-docker-and-why-is-it-so-darn-popular/
Virtual Machines vs. Containers

11. https://docs.docker.com/engine/introduction/understanding-docker/
Docker - Architecture

12. Docker - Layering
https://docs.docker.com/engine/userguide/storagedriver/imagesandcontainers/

13. Docker at scale with Kubernetes

14. Everything at Google
runs in containers
Launch over 2 billion
containers per week.

15. web browsers
BorgMaster
link shard
UI shardBorgMaster
link shard
UI shardBorgMaster
link shard
UI shardBorgMaster
link shard
UI shard
Scheduler
borgcfg web browsers
scheduler
Borglet Borglet Borglet Borglet
Config
file
BorgMaster
link shard
UI shard
persistent store
(Paxos)
Binary
Developer View
What just
happened?

16. Enter Kubernetes
Greek for “Helmsman”; also the root of
the word “Governor”
• Container orchestrator
• Runs containers
• Supports multiple cloud and
bare-metal environments
• Inspired and informed by Google’s
experiences and internal systems
• Open source, written in Go
Manage applications, not machines

17. web browsers
Scheduler
kubectl web browsers
scheduler
Kubelet Kubelet Kubelet Kubelet
Config
file
Kubernetes Master
Container
Image
Developer View
What just
happened?

18. Kubernetes - Architecture
https://en.wikipedia.org/wiki/Kubernetes

19. http://www.slideshare.net/kitmerker/devnexus-2015-kubernetes-container-engine

20. Pods, Replication sets & (auto)scaling
Pod
con-
tainer
con-
tainer
Deployment
Replication Set
Pod
con-
tainer
con-
tainer
Pod
con-
tainer
con-
tainer

21. Services
Pod
con-
tainer
con-
tainer
Service
Cluster IP:port <10.0.0.20:80>
Node IP:port <10.150.42.191:88>
Pod
con-
tainer
con-
tainer
Pod
con-
tainer
con-
tainer
Loadbalancer
Kube Proxy
(IP Tables)
API server
Watches

22. Namespaces
PodDeployment Pod
Service
PodDeployment Pod
Service
Worker Node Worker Node

23. Worker Node
Persistent Storage Node
Persistent Volumes
Pod
con-
tainer
con-
tainer
Persisted Volume
Persisted Volume Claim
Persisted Volume Mount

25. Quintor
Resources
• Docker - Build, Ship, and Run Any App, Anywhere – www.docker.com
• Kubernetes - Accelerate Your Delivery – kubernetes.io
• Creating a Raspberry Pi cluster running Kubernetes –
tinyurl.com/rpi-k8s-cluster
@ArjenWassink