chennai hearts docker workshop - 3 - conclusion

CHENNAIHEARTSDOCKER

HOW IS THISCOMPARED TO...

AJIRA / HACK & LEARN / CHENNAI HEARTS DOCKER

SHELL SCRIPTS

▸Not idempotent▸If it fails in the middle, now it needs more work


TASK RUNNERS

▸Capistrano, Fabric▸Easier Shell Scripts, but Same mindset


CONFIGURATION MANAGEMENT

▸ Chef, Ansible, Puppet, Salt, etc▸ Diff current state and End statepackage “openjdk” do action :install ...directory “/var/www” do mode 0755 owner “nginx” group “root” …


IMMUTABLE INFRASTRUCTURE

▸State is the Enemy▸Always discard ephemeral server and deploy a fresh app

▸Vagrant, VM Images, Packer▸Huge, Slow, Expensive, Hardware Specific


CONTAINERS

▸Consistency of Immutable Infrastructure

▸Faster and Lighter than VMs▸Easily scripted by Developers▸Truly write once, run anywhere (duh, Linux)


BUT STATE…

▸State is never Dead▸Persistent = DB, Redis, Files, etc

▸Thus HTTPfication of infrastructure

▸But Manage it better▸Isolate Ephemeral vs Persistent


DON’T...

▸Persistent services▸Want to run Redis or Postgres like that in Production? Nah.

▸Or need a lot of shared folders?

▸Need persistent storage?


DON’T...

▸Custom config files▸Relying too much on shared folders

▸Git clone when running the image

▸Relying on Container Links▸Relying on Shared Volumes


DO...

▸Ephemeral Services▸APIs, Background Jobs, Data crunching, Sandboxing, Tests

▸Combine Docker with Chef/Ansible/Puppet/etc▸Its fine really


DO...

▸Cloud Services▸Amazon EBS with Docker

▸Amazon ECS▸Hosted Kubernetes


EXPERIMENT...

▸Network Overlay▸Clustering▸Distributed Shared Volumes▸Mesos Data Center OS▸PaaS (Deis, Flynn, Dokku-alt)▸Some tools more mature than others

AJIRAHEARTSDOCKER

www.ajira.tech@rdsubhas

@arvindkumarc

chennai hearts docker workshop - 3 - conclusion

Technology