Intro in Docker and containerization

1. Docker Containers Deep Dive
Best of Red Hat Summit
Will Kinard
October 4, 2016

2. Agenda
2
• Intro
• Containerization 101
• Use Cases
• Build, Ship, Run
• OpenShift
• Q&A

3. 3
• DevOps Advisory and Implementation
Services
• Docker Consulting and Integration
• CloudBees Jenkins Consulting
About
The Container Enablement Company
• Continuous Integration,
Delivery, and Deployment
• Application Modernization
• Cloud Migration

4. Container Tech Isn’t New
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2000
2002
2004
2006
2007
1979
2008
2013
Chroot
Filesystem isolation
FreeBSD Jails
Early container technology
Linux Namespaces
Process isolation
Solaris Zones
Similar to jails; snapshots, cloning
Google Process Containers
Process aggregation for resource management
Linux Control Groups
Process containers renamed and merged into kernel 2.6.24
LXC Linux Containers
Userland tooling
DotCloud  Docker Inc.
Introduction of Docker Open Source Project

5. Docker Open Source Project
GitHub (github.com/docker/docker)
• 2900+ Contributors
• 10,000+ Active Forks
• 34,000+ Stars
Docker Hub (hub.docker.com)
• 6B+ Image Downloads
• 500,000+ Dockerized Applications
• Exponential growth
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0
1
2
3
4
5
6
2013 2014 2015 2016
Docker Pulls - Billions

6. What is a Docker Container ?
• Method to run applications in isolation
• Isolation includes namespacing pid, network, users, restricting
root, cpu and memory limits, and providing separate
filesystem
• Many of the technologies are old, but haven't been packaged
in an easy to use toolset before Docker
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“Docker containers wrap up a piece of software in a complete filesystem that contains everything it needs
to run: code, runtime, system tools, system libraries – anything you can install on a server.”
(https://www.docker.com/what-docker)

7. Containerized Deployment and Scaling
Each virtual machine
includes:
- application
- binaries and
libraries
- entire guest
operating system
Containers:
- Include application and all dependencies
- Share kernel with other containers
- Run as an isolated process not tied to any
specific infrastructure
Virtual Machines Containers
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8. 8
We’re not trying to replace your VMs
Virtual Machine:
Host Virtualization
Containers are used in
partnership with current IaaS
stacks.
Docker and other container
platforms still need a host.
Container:
Application Virtualization
Take advantage of the streamlined
process for VM based IaaS and gain
efficiencies in:
• Higher density workloads
• Scale
• Portability
• Security

9. 9
Portability is Empowering

10. 10
Portability is Empowering

11. 11
Portability is Empowering

12. 12
• Containers are designed to be disposable
• New containers go back to a clean image state
• Running containers write to an isolated space
Immutable
• Data is stored outside of the container
• Separates data from your application

13. 13
Application Development (Build & Ship)
Problem: Code migration issues: Dev  Test  Prod. Painful and slow software delivery.
Solution: Developer Self-Service. Automate and consolidate with Docker.
Docker packages applications and their dependencies into containers to allow for easy transport from a
developers laptop to any target test or prod environment. This accelerates the software lifecycle,
increases reliability, and reduces job time.
- Begin with a “Trusted Known State”
- Control and Approve Content
- Track Promotion CryptographicallyDeveloper
Version
control
Sysadmin
QA / QE

14. 14
Application Modernization / Cloud Migration
Problem: Legacy applications: brittle, and difficult to change/bug fix/upgrade
Hard to scale, obsolete APIs, costly and difficult to support and maintain.
Solution: Microservices architecture. Technology diversity. Modular boundaries.
Mulit-tier applications can be deployed in parts and each tier is an independent container. Each of the containers
can be used for a single service. Legacy applications can be migrated to the cloud through either a “lift & shift” or
“refactoring” methodology, or potentially a combination.

15. Build
Docker Images
• Images are the definition. They include
the filesystem, environment variables,
and default entry points.
• Containers are an instance of an
image. They isolate the application
from the host, and even from other
containers.
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16. Build
Dockerfiles
• Write your image definition in a Dockerfile
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• Turn that Dockerfile into an image with
• Develop a new app or “lift and shift” your current codebase

17. • Union file system
• Multiple RO layers are stacked
• Containers add a single RW layer to
isolate changes
• Layers are cached for fast builds
• Layers are named with a hash inside
the engine
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Docker Images

18. Docker for Mac / Windows
• Docker tools for the developer
• OS native clients using internally
available virtualization: xhyve and
Hyper-V
• Full Docker CLI from native OS
shell
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Red Hat Container Dev Kit
• Pre-built container development
environment
• Choice of virtualization platforms:
Virtualbox, Hyper-V, Linux KVM
• Eclipse and docker CLI integration

19. Ship
Docker Registry (and Hub)
• Push and pull to central registry
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• Organized as repositories that contain
multiple tags
• Multiple options: run your own, Docker
Hub, OpenShift, 3rd parties

20. Run
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• Run your image
• Launches a container base on your image
• Options for:
 Volumes: link external data into the container for persistence
 Networking: bridged, overlay, access with exposed ports

21. Run
Distributed
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• Fault tolerant
• Blue/Green Deployment
• Seamless rollbacks

22. Distributed
Docker Compose
• Packages multiple containers together
• Defines parameters for ‘docker run’
• Configuration is stored in ‘docker-
compose.yml’
• Allows containers to be scaled, but
without orchestration
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23. Docker on Red Hat
RHEL
Consistent performance and reliability
Certification and Support
SELinux Security
Atomic Host
• Minimal footprint operating system
• Linux container optimized
• Reliability and security of RHEL
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24. Red Hat OpenShift Container Platform V3
OpenShift and Kubernetes add the ability to orchestrate
docker containers across multi-host installations.
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• Self-service Platform
• Multi-language Support
• Application Persistence
• Automation
• OpenvSwitch Integration
Load Docker Images to OpenShift!
# oc new-project rhsummit
# oc new-app gitlab/gitlab-ce

25. Thank You!
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Will Kinard
CTO BoxBoat Technologies
will@boxboat.com
@boxboat
www.boxboat.com/blog

26. Appendix
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27. This is Important
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28. 28
• Isolated space for a running application
• All containers run on the same kernel unlike a VM
• Eliminates the overhead of an OS and services
Come Again?

29. Docker Containers – Run… Anywhere?
Linux:
Kernel Version 3.10+
• Ubuntu 13.10+
• Fedora 20+
• RHEL 7+
• CentOS 7.1+
• Gentoo
• ArchLinux
• openSUSE 13.1+
• CRUX 3.0+
Windows (Really!):
• Docker for Windows
• Windows Server 2016 (TP5)
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Docker for ARM!

30. Production Operations / Data Center
Problem: Inefficiency of VMs .. O/S duplication… Lengthy boot and replication times.
Hardware, Storage, and Hypervisor costs $$.
Solution: Docker’s containers as a service (CaaS) and orchestration platform. Policy driven architecture.
Deployment flexibility (On-Premise, Cloud, Hybrid).
Docker containers share resources with the host OS, which makes them significantly more efficient than VMs.
Containers can be started and stopped in a fraction of a second. They are lightweight, fast, and maximize
consolidation. Swisscom reduced their VM footprint from 400 to 20 for a database as a service offering, driving
tremendous cost savings.

31. Control
Manage and secure
at scale
Portability
Frictionless
Movement & Trust
Agility
Innovation at
speed
+ +Build Ship Run
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32. 32
Isolated
• Isolated filesystem
• Namespace for isolating pids
• cgroups for limiting memory and CPU
• Separate network stack
• Restricted root capabilities

33. Docker Notary
• Open source project on github
(github.com/docker/notary)
• Trusted cross platform content
distribution
• Platform agnostic in delivering
content
• Publisher key validates integrity
of content
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34. Portable
• Run Docker containers
unchanged in any
environment, on any
infrastructure
• Move applications at
will between
environments and
infrastructures
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35. At Scale
Docker containers spin up and down in seconds,
making it easy to scale application services to
satisfy peak customer demand, and then reduce
running containers when demand ebbs.
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