[NYC Meetup] Docker at Nuxeo

Docker at Nuxeo

Who we are

What is Nuxeo platform

• A platform to develop you own content apps

• Highly pluggable thru extension points

• Model you content with Nuxeo Studio

• Point and click UI to define your business model

• with hot-reload

Nuxeo tech. stack

• Java stack : Seam + JSF for Nuxeo DM and DAM

• Rest API to build your JS Apps

• Nuxeo Studio (Saas) to model your business

• Thru data model (doc types, schemas)

• Thru Automation chains

Nuxeo in the cloud ?

Goals

• Customers ask to host their app

• Provide quick access to test instances (onboarding)

• Provide onDemand dev or CI instances

Goals

• Customers ask to host their app

• Provide quick access to test instances (onboarding)

• Provide onDemand dev or CI instances

This is the nuxeo.io promise

First attempt

Manual OnDemand

• Based on AWS CloudFormation

• Manually deployed

• Works but :

• not scalable

• manual admin & monitoring

• difficult upgrade process

Second attempt

AWS Automation

• Provisionning may be automated

• Working mockup (python, celery, boto) but…

• Strong adherence to AWS

• difficult to test

• slow provisionning (one EC2 instance per Nuxeo instance)

• upgrade process still difficult

• scaling out is difficult

• sensible to failures

This leads to our challenge

Current challenge

• Build a scalable infrastructure

• Quick provisioning (less than a minute)

• Easy setup (no admin needed)

• Easy upgrade process

• Automated healing

• Easy to test

How Docker solves some of these issues ?

Quick provisioning

• We don’t have to start a server

• No VM overhead

• Start time is Nuxeo start time

Data free containers

• Docker container doesn’t hold data

• Upgrading is just using a new version of the image

• Healing means killing and restarting

Nuxeo v5.9.3

S3Postgres





S3Postgres





S3Postgres

Nuxeo v5.9.4

Several containers per server

• Scaling is just a matter of starting several containers

• But means infinite CPU / RAM and IO

Nuxeo.io server

io container

NXIO-0001

io container

NXIO-0002

io container

NXIO-0003

io container

NXIO-XXXX

…

Challenge status






• Easy to test

How to solve the other issues ?… with a little help from my friends

The infinite resource computer…

… is a cluster

Docker is not sufficient

• Docker handles processes at the OS level

• On the cluster level we need a companion

• To load balance the processes

• To check the statuses of the processes

• We need a docker ps at the cluster level

Introducing CoreOS

• A minimal Linux distribution (small footprint)

• Designed to handle cluster

• Providing cluster tooling

• Docker

• etcd

• fleet

https://coreos.com/

https://coreos.com/

etcd : service discovery

• etcd is

• small distributed key value store

• keys may have TTL

• using Raft protocol to elect cluster leader

• suitable for :

• shared configuration

• service discovery

fleet : clustered init system

• fleet is :

• an init system at the cluster level

• compatible with systemd unit files

• suitable for :

• launching docker containers

• distributing load across cluster

• get the status of the jobs

fleet demo

• Deploy our nuxeo container in the cluster

Challenge status






• Easy to test

What are the admin tasks ?

• Launch the fleetctl command

• Setup DNS and reverse proxies

• Link container to external services (S3, Postgres etc…)

DNS and reverse proxy

• docker start containers and link host port to container port

• The cluster has to redirect calls to mycustomDNS.io to the running container meaning knowing

• the ip of the host

• the port on the host

Introducing Gogeta

!/services/NXIO-0001/location:{host:172.31.51.1,port:49153}! /status/current:started! /expected:started!!! ! ! ! ! /alive:1!/domains/mydomain.nuxeo.io/type:iocontainer! /value:NXIO-0001

Given this etcd configuration

ClusterCoreOS

172.31.51.20

etcd

io container

NXIO-0098

systemd

CoreOS 172.31.51.1

etcd

io container

NXIO-0001 Gogeta

systemd

… … … …

Fleet

…

Gogeta

…

Introducing GogetaRound robin load Balancer

etcd !/services/NXIO-0098/location:{host:172.31.51.20,port:49153}! /status/current:started! /expected:started!!! ! ! ! ! /alive:1!/domains/mydomain.nuxeo.io/type:iocontainer! /value:NXIO-0001

Introducing Gogeta

• Easy to start as a docker container

!

!

• Written in Go

• Available at : http://github.com/nuxeo/gogeta

/usr/bin/docker run --rm --name gogeta -p 7777:7777 nuxeo/gogeta

http://github.com/nuxeo/gogeta

Application startup unit!

[Unit]!

Description=Sample startup script!

!

[Service]!

ExecStartPre= Set starting status in etcd!

ExecStart= Launch docker container!

ExecStartPost= Wait container to be launched and set app location in etcd!

ExecStop= Stop docker container!

ExecStopPost= Set stopped status in etcd!

Linking services

• Docker recommend to use ambassadors to link services

• Service may be hosted on other servers or outside of the cluster

• We’ve implemented dynamic ambassadors

• http://coreos.com/blog/docker-dynamic-ambassador-powered-by-etcd/

http://coreos.com/blog/docker-dynamic-ambassador-powered-by-etcd/

ClusterCoreOS

172.31.51.20

etcd

Postgres

systemd

CoreOS 172.31.51.1

etcd

io-container NXIO-0001

systemd

… … … …

Fleet

postgres-amb

Dynamic ambassador

etcd !/services/postgres/location:{host:172.31.51.20,port:49159}!

https://github.com/nuxeo/etcd-netfw


Dynamic ambassador

• Very easy to start

!

• Uses https://github.com/nuxeo/etcd-netfw

docker run --rm --name postgres-amb -P nuxeo/service-amb postgres-service


Launching commands

• A manager web app now launches commands :

• sets up basic etcd values (like domain to service resolution)

• launches fleet commands (start & stop apps)

• polls statuses

Challenge status






• Easy to test

Let’s resume

From nuxeo.io…

• We’ve built a cluster infrastructure that :

• knows how to deploy Docker containers (with fleet)

• Expose those containers thru domain name resolution (with gogeta)

• Link dependent services to the container (with etcd-netfw)

From nuxeo.io…

• Given that a container should represent an application

• Running this apps means :

• Launch it with runtime parameters

• Link it to its dependent services

• Then we can build a metamodel around it

…

name: io-container!version: 1.0!params:! - env_tech_id: ! - description: The id of the environment to run! - type:string! - clid:! - description: a registered connect client ID! - type:string!!buildimage:! path: "./docker"!!dependencies:! - postgres.service! - s3.service!!

… to arken

• to be able to run any application

!

• it will take care of :

• Submitting the model to the cluster

• Building the image if needed

• Launching the container

• Registering everything in etcd

arkenctl start iocontainer.ark —domain myapp.mycluster.io

Arken status

• We are extracting things from http://github.com/nuxeo/nuxeo.io

• http://github.com/arkenio

• home of gogeta and etcd

• provide cluster init instruction

• arken and arkenctl tools needs to be done

• new opensource projects (not in nuxeo repo)

• pull requests are welcome

http://github.com/nuxeo/nuxeo.io

http://github.com/arkenio

Conclusion

• Docker helped us to enter the micro containers world

• Lots of new features : multi-repo, automatic /etc/hosts etc…

• CoreOS provided us cluster deployment

• Arken wants to provide a higher deployment model

Time for questions@damienmetzler

[NYC Meetup] Docker at Nuxeo

Technology

Transcript of [NYC Meetup] Docker at Nuxeo