A Gentle (Hands-on) Introductionto Container Orchestration withDocker Swarm, Kubernetes, Mesos

Dippy AggarwalPh.D. Candidate, University of Cincinnati, Ohio

Dippy Aggarwal Dissertation focus: Graph databases (Neo4j), data warehouses, schema evolution and provenance

Summer Intern 2016 at Cincinnati Children’s Hospital, Biomedical Informatics, High Performance Computing Team

High Performance Computing Team, Biomedical Informatics,

Cincinnati Children’s Hospital

Carmen De VitoPrakash Velayuthum

Roberto Perea

Kevin Sandy

Mark Cunningham Jason Curtis

OutlineMotivation: To present a conceptual and hands-on introduction for deploying Neo4j containers across a cluster using the three popular container orchestration tools –

Docker Swarm, Kubernetes and Mesos.

Orchestration 101

Overview of three orchestration tools: Kubernetes, Docker Swarm and Mesos

Demos – Automated cluster deployment of neo4j with the three orchestration approaches

What is Docker/Containerization all about?

Ships goods Ships software

Stackable, portable, isolated

What purpose does containers solve in general?

[1] http://www.computerweekly.com/feature/Demystifying-Kubernetes-the-tool-to-manage-Google-scale-workloads-in-the-cloud[2] The Docker Book: Containerization is the new virtualization, James Turnbull, https://www.docker.com/what-docker

• Avoid “Runs on my machine” issues• Package your application as a standardized unit

Docker Progression (contd.)

Docker Adoption Is Up 30% in One Year 2/3 of Companies That Try Docker Adopt It

Adopters 5x Their container Count within 9 Months Docker Now Runs on 10% of the Hosts We Monitor

Source: https://www.datadoghq.com/docker-adoption/

https://github.com/neo4j/docker-neo4j/blob/master/2.3.5/Dockerfile

Environment variables

Download and install Neo4j

Exposing ports

Running neo4j on start

Neo4j dockerfile

docker build –t neo4j:2.3 .docker run –publish 7474:7474 –publish 7473:7473 neo4j:2.3

The Challenge• Containers by themselves are difficult to scale, achieve fault-tolerance• How to handle replication?• How to make multiple containers communicate?

How to deploy and manage multiple containers across a cluster of machines?

Orchestration is this idea of going from launching a container on one machine to multi-containers spread across a fleet of machines.

Orchestration Tools Survey

Kubernetes, Docker Swarm and Mesos – among the

leading products

http://thenewstack.io/tns-research-present-state-container-orchestration/

Last year@GraphConnect SF 2015

GraphConnect 2015 David Makogon, Microsoft and Patrick Chenzon, Docker - Containerized Neo4j: Automating Deployments with Docker

https://neo4j.com/blog/neo4j-containers-docker-azure/

Docker Swarm

Single Docker Engine Docker Swarm

- Native tool by Docker- Serves the standard Docker API 

Swarm-manager• Add additional nodes to the cluster seamlessly• Support single pool of resources• Maintains state of all the containers running on different docker engines• Make scheduling decisions

Image credits: http://www.slideshare.net/rajdeep/docker-swarm-introduction

Scheduling in Docker Swarm

Spread strategy: Swarm optimizes for the node with the least number of containers. Binpack strategy: Swarm optimize for the node which is most packed.

Swarm scheduler strategies

Running two containers on the same hostRunning containers on nodes meeting certain constraints: health checks, storage etc.docker tcp://<manager_ip:manager_port> run -d --name logger -e affinity:container==frontend logger

Swarm filters

Docker swarm cluster-setup

Commands to set up a Swarm cluster

Create discovery tokensdocker-machine create –d virtualbox localdocker run swarm createexport TOKEN=<token obtained from the last command>

Launching master and two agent nodes forming a cluster

Master: docker-machine create –d virtualbox --swarm --swarm-strategy=binpack --swarm-master --swarm-discovery token://${TOKEN} swarm-master Agent: docker-machine create –d virtualbox –swarm --swarm-discovery token://${TOKEN} swarm-agent1

Optional. Default strategy is spread

Demo: Deploy Neo4j Docker Container locally (VirtualBox) using Docker Swarm

Docker SwarmPros and Cons

+ Simplicity+ With Docker 1.12, several advanced features such as filters, auto-scaling made simpler

- Limited by Docker API functionality

docker service create –name frontend –replicas 5 -p 80:80/tcp nginx:latestScaling: docker service scale frontend=100

What is Kubernetes• Container Orchestration tool developed by Google but

many participants• Container cluster manager

Image credit: http://www.webopedia.com/TERM/G/google-container-engine.html

Kubernetes- core concepts• Pod• Service• Replication Controller• Deployment

• Etcd• API server• Scheduler• Kubelet daemon• Kube-proxy

Service

Replication Controller

Understanding Kubernetes Primitives

Image credits: https://keithtenzer.com/2015/06/01/application-containers-kubernetes-and-docker-from-scratch/

Hands-On: Deploy Neo4j Docker Container on Google Cluster using Kubernetes

Kubernetes - Pros and Cons+ Driven by Google+ Provides more concepts than Swarm+ Docker 1.12 leveraging Kubernetes idea of abstraction using pods and services

Cluster Manager

How Mesos help

Image Credits: http://www.slideshare.net/charmalloc/introductionapachemesosjstein20140714?next_slideshow=2

How does Mesos help?

No static cluster partitioning required

Mesos offers a level of abstraction

Interleaved workloads

Another stack variation for Mesos

Use Kubernetes as container management tool

Can even have heterogeneous cluster : private and cloud

Mesos – core components• Master: Mediator between the underlying resources and the different

frameworks.-- Makes offers to frameworks about available resources and launches tasks on slaves for accepted offers. • Slaves: actual workhorses of the cluster.-- Execute tasks submitted by frameworks. • Frameworks: applications that run on Mesos and solve a specific use-case.-- Two components: Scheduler and Executor.

Hands-On: Deploy Neo4j Docker Container using Mesos/Marathon

Which one to choose?• Use Docker Swarm if:

You want to use the familiar Docker API to build Docker containers• Use Kubernetes if: - You want to launch pods, which are groups of containers co-scheduled and co-located together, sharing resources.

- You are a google fan!• Use Marathon if: You want to launch Docker or non-Docker long-running apps/services.

Choose your own adventure!

References• http://talkincloud.com/cloud-computing-and-open-source/081914/mesosphere-launches-clusters-

google-compute-engine• http://events.linuxfoundation.org/sites/events/files/slides/CloudOpen14MesosKubGCE%20(1).pdf• "Mesos: The Operating System for your Cluster“, David Greenberg, https://www.youtube.com/watch?

v=gVGZHzRjvo0, Published: 09-21-2014• Building Web Scale Apps with Docker and Mesos, Alex Rukletsov, https://www.youtube.com/watch?

v=UdHG170jBxs, Published: 01-07-2015• http://stackoverflow.com/questions/29198840/marathon-vs-kubernetes-vs-docker-swarm-on-

mesosphere-with-docker-containers• https://open.mesosphere.com/advanced-course/installing-software/• Comparison Guide: https://apprenda.com/thank-you/gaw-container-orchestration-comparison-guide/

Thank you!

Questions/Feedback?