IntroductiontoDockerPeng XiaoGitHub: xiaopeng163Network Consulting EngineerCisco Systems

Contents• The Metrix from Hell• What is Container/Docker?• Docker Basic Usage• Docker Networking Deep Dive• Docker Compose• Docker Swarm• Ecosystem and Standardization

Static website

Web frontend

User DB

Queue Analytics DB

Background workers

API endpoint

nginx 1.5 + modsecurity + openssl + bootstrap 2

postgresql + pgv8 + v8

hadoop + hive + thrift + OpenJDK

Ruby + Rails + sass + Unicorn

Redis + redis-sentinel

Python 3.0 + celery + pyredis + libcurl + ffmpeg + libopencv + nodejs + phantomjs

Python 2.7 + Flask + pyredis + celery + psycopg + postgresql-client

Development VM

QA server

Public Cloud

Disaster recovery

Contributor’s laptop

Production Servers

TheChallengeMultip

licity

ofS

tacks

Multip

licity

of

hardware

environm

ents

Production Cluster

Customer Data Center

Doservicesandappsinteract

appropriately?

CanImigrate

smoothlyandquickly?

TheMatrixFromHell

Static website

Web frontend

Background workers

User DB

Analytics DB

Queue

Development VM QA Server Single Prod

ServerOnsite Cluster Public Cloud Contributor’

s laptopCustomer

Servers

? ? ? ? ? ? ?

? ? ? ? ? ? ?

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Static website Web frontend User DB Queue Analytics DB

Development VM

QA server Public Cloud Contributor’s laptop

DockerisashippingcontainersystemforcodeMultip

licityofStacks

Multip

licityof

hardware

environm

ents

Production Cluster

Customer Data Center

Doservicesandappsinteract

appropriately?

CanImigrate

smoothlyandquickly

…that can be manipulated using standard operations and run consistently on virtually any hardware platform

An engine that enables any payload to be encapsulated as a lightweight, portable, self-sufficient container…

Static website

Web frontend

Background workers

User DB

Analytics DB

Queue

Development VM QA Server Single Prod

ServerOnsite Cluster Public Cloud Contributor’

s laptopCustomer

Servers

DockereliminatesthematrixfromHell

WhyDevelopersCare

• Buildonce…(finally)runanywhere*• Aclean,safe,hygienicandportableruntimeenvironmentforyourapp.• Noworriesaboutmissingdependencies,packagesandotherpainpointsduringsubsequent

deployments.• Runeachappinitsownisolatedcontainer,soyoucanrunvariousversionsoflibrariesandother

dependenciesforeachappwithoutworrying• Automatetesting,integration,packaging…anythingyoucanscript• Reduce/eliminateconcernsaboutcompatibilityondifferentplatforms,eitheryourownoryour

customers.• Cheap,zero-penaltycontainerstodeployservices?AVMwithouttheoverheadofaVM?Instant

replayandresetofimagesnapshots?That’sthepowerofDocker

*Withthe0.7release,wesupportanyx86serverrunningamodernLinuxkernel(3.2+generally.2.6.32+forRHEL6.5+,Fedora,&related)

WhyDevops Cares?

• Configureonce…runanything• Maketheentirelifecyclemoreefficient,consistent,andrepeatable• Increasethequalityofcodeproducedbydevelopers.• Eliminateinconsistenciesbetweendevelopment,test,production,andcustomerenvironments• Supportsegregationofduties• Significantlyimprovesthespeedandreliabilityofcontinuousdeploymentandcontinuousintegrationsystems

• Becausethecontainersaresolightweight,addresssignificantperformance,costs,deployment,andportabilityissuesnormallyassociatedwithVMs

Contents• The Metrix from Hell

•What is Container/Docker?• Docker Basic Usage• Docker Networking Deep Dive• Docker Compose• Docker Swarm• Ecosystem and Standardization

Container History

http://kiwenlau.blogspot.com/2015/01/linux-container-technology-overview.html

Docker is nothing new, it just show in the right time

AppA

Containersvs.VMs

Hypervisor(Type2)

HostOS

Server

GuestOS

Bins/Libs

AppA’

GuestOS

Bins/Libs

AppB

GuestOS

Bins/Libs

AppA’

Docker

HostOS

Server

Bins/Libs

AppABins/Libs

AppB

AppB’

AppB’

AppB’VM

Container

Containersareisolated,butshareOSand,whereappropriate,bins/libraries

GuestOS

GuestOS

…resultissignificantlyfasterdeployment,muchlessoverhead,easiermigration,fasterrestart

WhyareContainerslightweight?

Bins/Libs

AppA

OriginalApp(NoOStotakeupspace,resources,orrequirerestart)

AppΔ

Bins/

AppA

Bins/Libs

AppA’

GuestOS

Bins/Libs

ModifiedApp

CopyonwritecapabilitiesallowustoonlysavethediffsBetweencontainerAandcontainerA’

VMsEveryapp,everycopyofanapp,andeveryslightmodificationoftheapprequiresanewvirtualserver

AppA

GuestOS

Bins/Libs

CopyofApp

NoOS.CanSharebins/libs

AppA

GuestOS

GuestOS

VMs Containers

Docker Inside

Docker Inside (Deep Dive)• ADeepDiveIntoLinuxContainersForEngineersInterestedInTheGrittyDetails. http://docker-saigon.github.io/post/Docker-Internals/• Cgroups,namespaces,andbeyond:whatarecontainersmadefrom?(DockerCon Europe2015) https://goo.gl/25KtpZ

Contents• The Metrix from Hell• What is Container/Docker?

•Docker Basic Usage• Docker Networking Deep Dive• Docker Compose• Docker Swarm• Ecosystem and Standardization

DockerEngine• DockerDaemon+REST(ish)API• DockerClient(CLI)talkstotheAPI• DaemonmanagestheDockercontainers• Startitwith:docker –d• docker versiontotestifdocker issetupcorrectly• DockerEngine(Linux,Mac,Windows)• https://docs.docker.com/engine/installation/

DockerToolbox• DockerToolboxisaninstallerforquicksetupandlaunchofaDockerenvironmentonolderMacandWindowssystemsthatdonotmeettherequirementsofthenewDockerforMacandDockerforWindowsapps.

DockerMachine• MachinemakesitreallyeasytocreateDockerhostsonyourcomputer,oncloudprovidersandinsideyourowndatacenter.Itcreatesservers,installsDockeronthem,thenconfigurestheDockerclienttotalktothem.• Driversexistfor:

• AWS• DigitalOcean• Azure• GoogleComputeEngine• Rackspace• OpenStack• Virtualbox• VMWareFusion• VMWarevSphere• Hyperv

Docker ImagesvsContainers• Images:Aboutstoringormovingyourapp• Containers:Aboutrunningyourapp

https://docs.docker.com/engine/userguide/storagedriver/imagesandcontainers/

Docker Workflow——Build/Pull/Push

SourceCode

Repository

DockerfileForA

DockerEngine

DockerContainerImageRegistry

Build

Docker

Host2OS(Linux)

ContainerA

ContainerB

ContainerC

ContainerA

Push

Search Pull

Run

Host1OS(Linux)

DockerImage• Download,list,removeimages

https://hub.docker.com/

DockerfileCreate a Dockerfile

Build a image

https://docs.docker.com/engine/reference/builder/

DockerContainer• Create and start a container

• Inside of the container

DockerContainer• Stop and remove a container

http://docker-k8s-lab.readthedocs.io/en/latest/docker/docker-cli.html

Contents• The Metrix from Hell• What is Container/Docker?• Docker Basic Usage

•Docker Networking Deep Dive• Docker Compose• Docker Swarm• Ecosystem and Standardization

Docker Networking

ContainerNetworkModel

https://github.com/docker/libnetwork/blob/master/docs/design.md

CNM Drivers

Demo: Docker Bridge Network• http://docker-k8s-lab.readthedocs.io/en/latest/docker/bridged-network.html

Docker Multi-Host Networking• Tunnel• Docker build-in overlay network: VXLAN• OVS: VXLAN or GRE• Flannel: VXLAN or UDP• Weave: VXLAN or UDP

• Routing• Calico: Layer 3 routing based on BGP• Contiv: Layer 3 routing based on BGP

http://blog.dataman-inc.com/shurenyun-docker-133/

Lab A: Overlay Multi-Host Networking with OVS• http://docker-k8s-lab.readthedocs.io/en/latest/docker/docker-ovs.html

Linux bridgedocker0

br-int gre0

eth0

eth0 eth0

Host 1Docker

Container 2Container 1

Open vSwitch

Linux bridgedocker0

br-intgre0

eth0

eth0 eth0

Host 2Docker

Container 2Container 1

Open vSwitchGRE tunnel

Lab B:Multi-Host OverlayNetworkingwithEtcd• http://docker-k8s-lab.readthedocs.io/en/latest/docker/docker-etcd.html

Docker1.12NetworkingModelOverview

Contents• The Metrix from Hell• What is Container/Docker?• Docker Basic Usage• Docker Networking Deep Dive

•Docker Compose• Docker Swarm• Ecosystem and Standardization

DockerComposeOverview• Composeisatoolfordefiningandrunningmulti-containerDockerapplications.WithCompose,youuseaComposefiletoconfigureyourapplication’sservices.Then,usingasinglecommand,youcreateandstartalltheservicesfromyourconfiguration.• Definedinyaml

Demo: Docker Compose• ExampleVotingApp• https://github.com/DaoCloud/example-voting-app

• Guide:• http://docker-k8s-lab.readthedocs.io/en/latest/docker/docker-compose.html

Contents• The Metrix from Hell• What is Container/Docker?• Docker Basic Usage• Docker Networking Deep Dive• Docker Compose

•Docker Swarm• Ecosystem and Standardization

Before Docker Swarm

With Docker Swarm

grpc

raftconsensusgroup

gossipnetwork

http://www.grpc.io/http://thesecretlivesofdata.com/raft/https://en.wikipedia.org/wiki/Gossip_protocol

Docker Orchestration Components

http://www.slideshare.net/ajeetraina/service-discovery-loadbalancing-under-docker-1120-docker-meetup-22

Create Docker Service

https://www.youtube.com/watch?v=_F6PSP-qhdAhttp://collabnix.com/archives/1445

Demo: Docker Swarm• Docker Swarm with Load Balancing and Scaling• http://docker-k8s-lab.readthedocs.io/en/latest/docker/docker-swarm-lb-scale.html

• Multi-Services issue• https://github.com/docker/compose/issues/3656

Contents• The Metrix from Hell• What is Container/Docker?• Docker Basic Usage• Docker Networking Deep Dive• Docker Compose• Docker Swarm

•Ecosystem and Standardization

Container Ecosystem

OpenContainerInitiative (OCI)• A Linux Foundation Collaborative Project• Free from control by any particular vendor’s specfic cloud stack orecosystem• Includes:• Container runtime specification -> runc• Image format specification

http://www.slideshare.net/PhilEstes/runc-the-little-engine-that-could-run-docker-containershttps://www.opencontainers.org/https://github.com/opencontainers

Container Networking• Container Network Model (CNM) by Docker• Adopted by Docker libnetwork, Cisco Contiv, Kuryr, OVN, Project Calico,Vmware, Vwave

• Container Network Interface(CNI) by CoreOS• Adopted by kuberntes, Kurma, rkt, Apache Mesos, Clould Foundry, CiscoContiv, Project Calico and Weave.

http://thenewstack.io/container-networking-landscape-cni-coreos-cnm-docker/https://github.com/containernetworking

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