Slides from a talk on Docker for a company considering implementation based on my experience so far.

1. 1
Docker in the Wild
Chris Mague / Shokunin
3/4/2016

2. 2
Today's Talk

Background

The Good

The Bad

In development

In CD pipelines

In production

Conclusion

3. 3
“Everyone needs a daily dose of Vitamin No”
-Reiko

4. 4
Why Virtualize at all?
- Big machine – small service
- Migration possible
- Legacy uses
- Simpler provisioning
- Isolation

5. 5
Background
- Virtualization
- VM vs Container
- Jails
- Solaris Zones
- Cgroups in Linux
- LXC
- Docker

6. 6
The Good

7. 7
Good Reasons to use Docker
0) Immutable
1) fast startup times
2) lightweight
3) good tools
4) great with microservices

8. 8
The Bad

9. 9
Docker Downsides
0) Immutable
1) requires Linux
2) only runs one process
3) tooling is awful (especially on not Linux)
4) troubleshooting is hard
5) need to rethink how you develop/deploy

10. 10
Immutable
“these are snowflakes
– chives are identical”
- Dinner Rush

11. 11
In Development

12. 12
But where do these containers come from?
There are some high quality
containers available for
download!

13. 13
Downloading things off the Internets

14. 14
D-I-Y

15. 15
Better Solution from Hashicorp
- use puppet/chef/salt/ansible
- still can use shell scripts
- output a variety of formats
- AMI
- GCE
- Droplets
- Virtual box
- Openstack
- Docker

16. 16
Running Containers
Docker Composer
- relatively simple
- works great on a dev
machine
- docker specific

17. 17
Better Solution from Hashicorp (2)
- Runs Docker Containers
- Modular / Variables can be set
- Controls a variety of services
- Consul
- GCE
- Droplets
- Mailgun
- Postgres/Mysql
- Datadog

18. 18

19. 19
In CI/CD – Example Jenkins Pipeline

20. 20
Now we come to scaling...
Treat a bunch of hardware as a
big local docker instance

21. 21
Or Amazon

22. 22
Better Solution from Hashicorp (3)
So do you work for them or something??
- Job scheduler
- Docker
- Java
- Binary
- QEMU
- Cron scheduler
- Orchestration
- Service discovery

23. 23
Job Specification

24. 24
New problem – Discovery!

25. 25
Better Solution from Hashicorp (4)
- single binary
- Raft consensus / HA
- Gossip protocol
- Rest API
- DNS Interface
- Key/Value store
- Locking

26. 26
DNS Discovery

27. 27
frontend http
bind 0.0.0.0:80
capture request header
Host len 500
{{range services}}{{ if .Tags |
contains "web-service" }}
acl host_{{ .Name }}
hdr_beg(host) -i {{ .Name }}.
use_backend {{ .Name }}
frontend http
bind 0.0.0.0:80
capture request header
Host len 500
acl host_tabinin
hdr_beg(host) -i tabinin.
use_backend tabinin if
host_tabinin
Config File / Templates

28. 28
Feature Flags – Consul generated file

29. 29
In Production
A few things have to change...

30. 30
Cattle vs. Pets
Pets:
- have cute names
- take them to the vet
- care and feeding
Cattle:
- replace it...

31. 31
SLAs/KPIs become critical
- If my service returns a response in < 200ms 95% of the
time...
- If my error rate > 2% over a 5 minute window...

32. 32
Monitoring / Telemetry must follow

33. 33
Logging is now your primary method of
troubleshooting

34. 34
New Problem
- You can deploy too fast……
Which one of the 10 deploys caused the issue and
which one fixed it?
Two deployment windows a day 11:00 and 3:00
means everyone is on hand and able to jump in if
there's an issue

35. 35
Conclusion (1)
You are going to end up with an infrastructure that consists of
Docker-ized and other types of services
Accordingly, pick the tool set that is the most flexible! (my bias
is clear here...)

36. 36
Conclusion (2)
Docker is worth it for some things:
- application servers
- stateless applications
- development environment
Don't bother:
- data stores
- slow moving monolithic apps