This document discusses microservices architecture and how containers can help solve problems with monolithic architectures. It describes how microservices break applications into independent, scalable services that communicate over standard protocols. Containers provide standardized, isolated environments for microservices. Using containers for microservices allows for easier deployment and management of distributed applications across infrastructure.

1. Microservices Architecture
and Containers.
Jacob Clark (@imjacobclark)

2. Monolithic architectures
● Fundamental components are interwoven
● Typically composed of Client, Server & Database
● Examples being WordPress, Jenkins, GitLab
● Changes mean complete compilation/redeploy
● Difficult to scale
● Generally easier to build
● Generally easier to deploy

3. Posts Content Users
Plugins DashboardThemes
WordPress
HTTP Server
MySQL

5. Microservices architectures
● An application built as a suite of small services
● Standalone, scalable & distributed
● Communicate over a standard protocol (REST, message queues)
● Programmatically react to failures
● Evolutionary architecture principle (don't microservice all the things...)
● Improved automation and delivery
● Not tied to a single language or framework

6. Client
Comments
Content
Plugins
Dashboard
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HTTP Server (Loadbalancing)
json
json
json
octet stream
json
html html
Themes
Themes
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Plugins
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DB adaptor
json

7. The problem
● omg boxes???
● Horrendous deployment times
● Maintaining large infrastructure
● A simple architecture now hugely complicated
● Cost is exponential
● Monitoring??
● Does my cloud provider even support programmatic
provisioning??

8. The solution... containers!
● Applications and their dependencies only (not an entire OS)
● Single kernel opposed to multikernel
● Built into the foundations of Unix (LXC, etc)
● Run as an isolated processes in userspace
● Resources are isolated from the host and other
containers (much like Virtualisation)
● Consistent, portable and packageable environments by
default (no need for Vagrant or Packer)

9. Putting them together...
● Microservices inside containers make for easy to
distribute services
● Developers can build on identical and consistent
environments
● Containers can be hosted on private repositories,
making individual service deployment faster (dependencies aren't
pulled from third party mirrors)
● Deployment build jobs are considerably smaller

10. ClientDashboard Themes
Plugins Comments
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DB
adaptor
Database
Host 02
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adaptor
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adaptor
Host 04
Host 01
HTTP Load Balancer
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Content

11. Docker
● It’s creating a container standard (libcontainer)
● Cross-platform thanks to Microsoft Azure
● 75’000+ pre-built `Dockerized` applications, including
Ubuntu, MongoDB & Node.
● Backed by eBay, Spotify, Rackspace, New Relic and
more

12. Dockerising a Node app...
server.js
package.json
Dockerfile
docker build -t bbc-example-app .
docker run -t -i -p 1337:1337 bbc-example-app

13. CoreOS
● OS designed for launching containers
● Built for clustering
● Built in service discovery with automatic failover
● Docker by default
● Backed by Google, Rackspace, Cisco and Mozilla

14. ● Fleet for centralised service management of
an entire cluster
● Systemd for cluster service management
● Etcd service discovery via a cluster
distributed key-value store
● Confd for dynamic configuration reloading
● https://github.com/imjacobclark/devnews-coreos
Scaling Node on CoreOS

15. kthxbi