Tell me...   what is it?

Containers

[ kontanje:re ]

Resource isolated space 

No Overhead

no emulation

no guest OS

almost

Linux Needed

LXC, cgroups, namespaces, etc...

we've heard Windows is coming :)

What if...

I want to test-drive

Scala stack?

Closure stack?

12 OpenSSHs on one machine?

4 balanced nginxes?

I want to test-drive

Scala stack?

Closure stack?

12 OpenSSHs on one machine?

4 balanced nginxes?

What if...

... one can use ...

RAM, CPU, ...

RAM, CPU, ...

9 equal nginxes already there ;)

docker run --rm -ti nginx

docker ps

docker ps -a

Dockerfile

Recipe to build image

wooohooo it's a shell

FROM dockerfile/java:oracle-java7

RUN useradd -m -s /bin/bash developer

RUN apt-get update && apt-get install -y mc

RUN apt-get install git-flow

ADD .alias /home/developer/

RUN export uid=1000 gid=1000 && \

mkdir -p /home/developer/opt && \

echo "developer:x:${uid}:${gid}:Developer,,,:/home/developer:/bin/bash" >> /etc/passwd

USER developer

ENV HOME /home/developer

CMD ["sudo", "/home/developer/entrypoint.sh"]

docker build --rm -t seges/mug-backend-java:oracle-7

docker images

docker images | grep nginx

Data

Service

Cron

nginx

spring boot

postgresql

80

One container

runit

Everything is container

nginx

spring boot

postgresql

80

spring boot

spring boot

postgresql

Scale

nginx

spring boot

app data

--volume-from

--link

--volume

/opt/docker/app/data

80

--publish

Container is everything

nginx

spring boot

app data

--volume-from

--link

--volume

/opt/docker/app/data

80

--publish

app config

Dockerize your dev environment

tools as containers

Mug Developer's toolkit

seges.github.io/mug/

$ git clone mypowerproject

$ cd mypowerproject-server

$ mug

34@89530> mvn clean install

$ cd mypowerproject-client

$ mug

9687d932> gulp build

docker run -ti --rm \
       -e DISPLAY=$DISPLAY \
       -v /tmp/.X11-unix:/tmp/.X11-unix \
       firefox

Fleet

What is still open

• how to orchestrate multiple hosts
• software defined networks
• proper service discovery
  • transparent in apps
• mass deployment
• and others...

Alternatives

Cutlery

seges.github.io/cutlery

Ambassador

Bash

Consul

Registrator

DNS

Good practice is good practice

Use volumes

keep in mind scalability

host persistent vs. not

Images from the Hub

don't use them blindly

check Dockerfile

Root?

do you use it on your host?

so try not to in the container

Size matters

use layers wisely

inherit images

Container environment

e.g. locale setup

often UTF-8 is forgotten

Security

drop privileges as soon as possible

although isolated, security rules still apply

Ports

Bound to the host

think twice because of scalability and discovery

Orchestration tool

fig.sh

or nice & formatted Bash scripts

ICC

networking between containers

icc=false

DevOps tool

but helps on app level as well

e.g. in creating /separating microservices

Everything is a container ;)

golden rule

Thank you...

@ladislavGazo

gazo@seges.sk

need a workshop? consulting? contact me...