Introduction to Flocker which is a lightweight volume and container manager. Meetup details of my presentation: http://www.meetup.com/Docker-Bangalore/events/222476025/

1. FLOCKER
~~~ Ravi~~~

2. Agenda
 Docker & Limitation
 Why Flocker? Features
 Flocker Support
 Flocker Flow
 Demo
 Volume Manager

3. Docker
“Automates the deployment of any
application as a lightweight, portable,
self-sufficient container
that will run virtually anywhere”

4. Docker Limitation
• Multiple Hosts
• Networking
• Same Hosts
• Communication between Services
• Orchestration and Clustering
• Control of containers
• Container management

5. Docker Orchestration
Flocker

6. Docker Orchestration

7. Why Flocker
• Multi-hosted Docker cluster management tool
• Managing data volumes attached to containers
• Git Hub, Open Source
Live Migration
“Stateful thing scale vertically, stateless things
scale horizantlly”

8. Features
• Seamless database migrations for your micro
services
• Integrates into your existing Docker workflow
• Run multiple containers on multiple machines
• Easily move between dev, staging, production

9. Databases Supports
o Databases
o Queues
o Key-Value Stores

10. Virtualization Supports

11. Flow

12. Configuration
"version": 1
"nodes":
"172.16.255.250": ["mongodb-volume-example"]
"172.16.255.251": []
"version": 1
"applications":
"mongodb-volume-example":
"image": "clusterhq/mongodb"
"ports":
- "internal": 27017
"external": 27017
"volume":
# The location within the container where the data volume will be
# mounted:
"mountpoint": "/data/db"
flocker-deploy deployment-config.yml application-config.yml
Deployment File Application File
CLI =>

13. Demo

14. Moving Example
– Without Volume Specification-

15. Moving Example
– Without Volume Specification-

16. Moving Example
– Without Volume Specification-

17. Moving Example
– Without Volume Specification-

18. Moving Example
– Without Volume Specification-

19. Moving Example
– Volume Specification-

20. Storage – ZFS
• ZFS: Storage analogue to containers for compute
independent snapshots and replication
• Storage container volumes across cluster
• Redundancy invariant

21. Volume Manager
Flocker manages ZFS file systems as Docker
volumes.
It attaches them to containers.
• Configuration
• Exposing Ports
• Size
• Cloning

22. Moving an Application
Volume Ownership
-Push
- Handoff
"version": 1
"nodes":
"172.16.255.250": ["mongodb-volume-example"]
"172.16.255.251": []
"version": 1
"nodes":
"172.16.255.250": []
"172.16.255.251": ["mongodb-volume-example"]

23. Cluster Architecture
• Control service
• Using HTTP API to modify cluster configuration
• Convergence Agents
• Modify the cluster state to match configuration

24. Flocker REST API
 GET /v1/configuration/containers
 POST /v1/configuration/containers
 POST /v1/configuration/containers/(name)
 DELETE /v1/configuration/containers/(name)
 POST /v1/configuration/datasets/(dataset_id)
 GET /v1/state/datasets

25. API Sample
GET /v1/configuration/containers POST /v1/configuration/containers

26. CLI Overview

27. Additional Slides

28. PowerStrip
• Data migration with Kubernetes and Flocker
• POC, Supports when Docker extensions become
official

29. PowerStrip Architecture

30. Flocker Routing
• Flocker - Routing
• Container configuration includes externally visible TCP port numbers.
• Connect to any node on a Flocker cluster and traffic is routed to the node
hosting the appropriate container (based on port).
• Your external domain (www.example.com) configured to point at all nodes in
the Flocker cluster (192.0.2.0, 192.0.2.1)
• Managing Routes
• Containers claim TCP port numbers with the application configuration that
defines them.
• Connections to that TCP port on the node that is running the container are
proxied (NAT'd) into the container for whatever software is listening for them
there.
• Connections to that TCP port on any other node in the Flocker cluster are
proxied (NAT'd) to the node that is running the container.
• Proxying is done using iptables.

31. Flocker Volume Manager
• Snapshots and replication of Flocker volume
• Push volumes to remote host
• Track changes
• Roll back to earliest states
• Models:
• ZFS – Clone, Replication
• BTRTFS

32. Thanks You..