1.
DOCKER NETWORKING
VĂN ĐÌNH PHÚC
TRẦN HỮU CƯỜNG
NGUYỄN VĂN THƯỜNG
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

2.
Networking Breakout
Madhu Venugopal
Jana Radhakrishnan

3.
AGENDA
 Introduction
 Networking Deep Dive (version 1.7)
 Networking Deep Dive (Experimental)
 Ecosystem
 Q&A
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

4.
INTRODUCTION
DOCKERDAY – VIET NAM - 2015 HN - 7/17/2015

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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

7.
LIBNETWORK
 Open Sourced in April
 Over 200 Pull Requests
 Over 200 GitHub Stars
 Windows and FreeBSD ports in progress

8.
LIBNETWORK
 Project Pages define the goals of each Platform Version Release and identify current
progress
https://github.com/docker/libnetwork/wiki
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015
Project Page Target Date Current Sprint Platform Version
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 - 7/17/2015

10.
DOCKER0 BRIDGE
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015
 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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015
 --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
HN - 7/17/2015
DOCKERDAY – VIET NAM - 2015
Iptables
Docker Host
8080/tcp
eth0
db
3306/tcp
• Wpuser
• wppwd
Wpdb
eth0
wp01
• /etc/host
• WORDPRESS_DB_NAME
=wpdb
• WORDPRESS_DB_USER
=wpuser
• WORDPRESS_DB_PASS
WORD=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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015
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
HN - 7/17/2015DOCKERDAY – VIET NAM - 2015

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 - 7/17/2015DOCKERDAY – VIET NAM - 2015

17.
NETWORKING DEEP DIVE (EXPERIMENTAL)
DOCKERDAY – VIET NAM - 2015 HN - 7/17/2015

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.

19.
“We'll do for Networking,
What Docker did for
Compute.”

20.
Goals
• Make “network” & “service” as top-level objects
• Provide a pluggable networking stack
• Span networks across multiple hosts
• Support multiple platforms

21.
Whats New?
• Updated Networking Stack in Docker
• Create Networks using the Docker CLI
• Multi-host Networking
• Services UI
blue = experimental

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

23.
Container Network Model
(CNM)
• Endpoint
• Network
• Sandbox

24.
Create
Network
Create
Container
Defer to
Driver
Defer to
Driver

25.
Libnetwork API
• libnetwork.New
• controller.ConfigureNetworkDriver
• controller.NewNetwork
• network.CreateEndpoint
• endpoint.Join

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

27.
Drivers
• Drivers implement the Driver API
• They provide the specifics of how a network and endpoint are
implemented

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

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)

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

31.
Networking Ecosystem

32.
– R. Callon, RFC 1925 - The Twelve Networking Truths
“One size never fits all.”

33.
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

34.
Q&A

35.
Thanks you
 Docker Hà Nội: http://www.meetup.com/Docker-HaNoi
 Văn Đình Phúc – phucvd.ce@gmail.com
 Trần Hữu Cường
 Nguyễn Văn Thường