This document summarizes a presentation on Docker networking. It introduces Docker networking concepts like the Docker0 bridge, virtual ethernet interfaces, linking containers, and editing networking configuration files. It then provides a deep dive on experimental Docker networking features in libnetwork like creating networks, multi-host networking, services, and drivers. The presentation encourages users to try experimental networking and contribute to libnetwork.

1. Docker
Networking
Văn
Đình
Phúc
–
System
Engineer
Nguyễn
Văn
Thường
–
Linux
Sysadmin
Trần
Hữu
Cường
–
R&D

2. Networking Breakout
Madhu Venugopal
Jana Radhakrishnan
Source: recap from DockerCon US 2015

3. AGENDA
¡ Introduction
¡ Networking Deep Dive (version 1.7)
¡ Networking Deep Dive (Experimental)
¡ Ecosystem
¡ Q&A
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4. INTRODUCTION
DOCKERDAY –VIET NAM - 2015 HN - 19/07/2015

5. WHAT IS DOCKER ?
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
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6. WHY IS NETWORKING IMPORTANT ?
¡ Communication between containers and the wider world
¡ Communication between containers in single host and multi hosts
¡ Container attached to multi networks
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7. LIBNETWORK
¡ Open Sourced in April
¡ Over 200 Pull Requests
¡ Over 200 GitHub Stars
¡ Windows and FreeBSD ports in progress
Source: recap from DockerCon US 2015

8. LIBNETWORK
¡ Project Pages define the goals of each PlatformVersion Release and identify current progress
https://github.com/docker/libnetwork/wiki
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Project Page Target Date Current Sprint PlatformVersion
libnetwork 0.5 10/06/2015 Docker 1.9.0
libnetwork 0.4 08/04/2015 Sprint 20 Docker 1.8.0
libnetwork 0.3 06/18/2015 Docker 1.7.0

9. NETWORKING DEEP DIVE (VERSION 1.7)
DOCKERDAY –VIET NAM - 2015 HN - 19/07/2015

10. DOCKER0 BRIDGE
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¡ Be a default bridge in Docker Hosts
¡ Randomly chooses an address and subnet
from the private range defined by RFC 1918
¡ Automatically forwards packets between any
other network interfaces that are attached to
it

11. VIRTUAL ETHERNET INTERFACES
¡ a pair of “peer” interfaces that are like opposite ends of a pipe — a packet sent on one will be received on the
other
¡ It gives one of the peers to the container to become its eth0 interface and keeps the other peer, with a unique
name like veth37c1271
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12. BINDING CONTAINER PORTS TO THE HOST
¡ docker run:
¡ -P or --publish-all=true|fals
¡ -p SPEC or --publish=SPEC
¡ -p IP:host_port:container_port
¡ -p IP::port
¡ --ip=IP_ADDRESS
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¡ --expose <port>
¡ EXPOSE line in the image’s
Dockerfile
orand

13. LINKING CONTAINERS TOGETHER
¡ docker run --name db -d -e MYSQL_ROOT_PASSWORD=Memzoh78
-e MYSQL_DATABASE=wpdb -e MYSQL_USER=wpuser -e
MYSQL_PASSWORD=wppwd mysql
¡ docker run --name wp01 --link db:mysql -d -e
WORDPRESS_DB_NAME=wpdb -e
WORDPRESS_DB_USER=wpuser -e
WORDPRESS_DB_PASSWORD=wppwd -p 8080:80 wordpress
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Iptables
Docker Host
8080/tcp
eth0
db
3306/tcp
• Wpuser
• wppwd
Wpdb
eth0
wp01
• /etc/host
• WORDPRESS_DB_N
AME=wpdb
• WORDPRESS_DB_US
ER=wpuser
• WORDPRESS_DB_PA
SSWORD=wppwd
eth0
Mysql:// 80/tcp

14. Docker Host
eth0L0
docker0
HOW DOCKER NETWORKS A CONTAINER ?
¡ option to docker run :
¡ --net=bridge (default)
¡ --net=host
¡ --net=container:NAME_or_ID
¡ --net=none
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db
• Wpuser
• wppwd
Wpdb
L0
Veth***eth0
3306/tcp
¡ docker run --name db -d -e MYSQL_ROOT_PASSWORD=Memzoh78 -e MYSQL_DATABASE=wpdb -e MYSQL_USER=wpuser -e
MYSQL_PASSWORD=wppwd mysql

15. EDITING NETWORKING CONFIG FILES
¡ with Docker v.1.2.0, you can now edit /etc/hosts, /etc/hostname and /etc/resolve.conf in a running container
¡ changes to these files will not be saved by docker commit nor will they be saved during docker run
¡ won’t be saved in the image, nor will they persist when a container is restarted
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16. ADVANCED NETWORKING TOOLS (THIRD PARTIES)
¡ Pipework (Jérôme Petazzoni)
https://github.com/jpetazzo/pipework
¡ Foundations of Python Network Programming (Brandon Rhodes)
https://github.com/brandon-rhodes/fopnp/tree/m/playground
¡ WEAVE
https://github.com/weaveworks/weave
HN - 19/07/2015DOCKERDAY –VIET NAM - 2015

17. NETWORKING DEEP DIVE (EXPERIMENTAL)
DOCKERDAY –VIET NAM - 2015 HN - 19/07/2015

18. Why is Networking important?
• Traditional Networking is incredibly vast and complex
• Networking is an inherent part of distributed applications
• Make it developer-friendly & application driven.
Source: recap from DockerCon US 2015

19. “We'll do for Networking,
What Docker did for
Compute.”
Source: recap from DockerCon US 2015

20. Goals
• Make “network” & “service” as top-level objects
• Provide a pluggable networking stack
• Span networks across multiple hosts
• Support multiple platforms
Source: recap from DockerCon US 2015

21. Whats New?
• Updated Networking Stack in Docker
• Create Networks using the Docker CLI
• Multi-host Networking
• Services UI
blue = experimentalSource: recap from DockerCon US 2015

22. What is Libnetwork
• Library for creating and managing network stacks for containers
• Test daemon/client called "dnet"
• Driver-based networking
• Implements the Container Network Model
Source: recap from DockerCon US 2015

23. Container Network Model
(CNM)
• Endpoint
• Network
• Sandbox
Source: recap from DockerCon US 2015

24. Create
Network
Create
Container
Defer to
Driver
Defer to
Driver
Source: recap from DockerCon US 2015

25. Libnetwork API
• libnetwork.New
• controller.ConfigureNetworkDriver
• controller.NewNetwork
• network.CreateEndpoint
• endpoint.Join
Source: recap from DockerCon US 2015

26. RESTful API
• Provides CRUD for Networks and Endpoints
• /network
• /network/<network_id>/endpoints
• /network/<network_id>/endpoints/<endpoint_id>
• /network/<network_id>/endpoints/<endpoint_id>/containers
• /services
• /services/<service_id>
• /services/<service_id>/backends
Source: recap from DockerCon US 2015

27. Drivers
• Drivers implement the Driver API
• They provide the specifics of how a network and endpoint are
implemented
Source: recap from DockerCon US 2015

28. Bridge Driver
• Creates a Linux Bridge for each network
• Creates a veth pair for each endpoint
- One end is attached to the bridge
- The other appears as eth0 inside the containers
• iptables rules created for NAT
Source: recap from DockerCon US 2015

29. Overlay Driver
• Creates a separate network namespace for every network
- Facilitates overlapping IP address space across networks
• Creates a Linux Bridge and VXLAN tunnels to every other discovered
host
• Creates a veth pair for each endpoint
- One end is attached to the bridge
- The other appears as eth0 inside the container
• Network namespace connected to host network using NAT
- Facilitates exiting the overlay network at every host(for external connectivity)
Source: recap from DockerCon US 2015

30. Network Plugins
• Implemented using libnetwork's remote driver
• Uses JSON-RPC transport
• Can be written in any language
• Can be deployed as a container
Source: recap from DockerCon US 2015

31. Networking Ecosystem
Source: recap from DockerCon US 2015

32. – R. Callon, RFC 1925 - The Twelve Networking Truths
“One size never fits all.”
Source: recap from DockerCon US 2015

33. Source: recap from DockerCon US 2015

34. Call to Action!
• Try the Docker Experimental Channel!
- https://experimental.docker.com
• Contribute to libnetwork
- Raise an Issue or Submit a Pull Request
• Chat with us on IRC
- #docker-network on Freenode
• Stop by at the booth for a demo
Source: recap from DockerCon US 2015

35. Q&A
Source: recap from DockerCon US 2015

36. Thanks you
¡ Docker Hà Nội: http://www.meetup.com/Docker-HaNoi
¡ Văn Đình Phúc – phucvd.ce@gmail.com
¡ Trần Hữu Cường - tranhuucuong91@gmail.com
¡ NguyễnVăn Thường - thuongnvbk@gmail.com
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