The document discusses using Docker and configuration management tools like Ansible and Chef together. It provides examples of building Docker images from code using tools like SBT and Maven. It also describes using Ansible playbooks and Chef recipes to automate pulling, running and managing Docker containers. Configuration files and credentials can be handled securely. Overall, the document shows how Docker and configuration management can be integrated to provide an automated and flexible deployment pipeline.

1. DOCKER AND
CONFIGURATION
MANAGEMENT
PUNE DOCKER MEETUP, 25 APRIL 2015
MUKTA APHALE

2. AGENDA
• Use Case: Considering Docker in Production
• Configuration Management and Docker
• Docker and Ansible
• Docker and Chef
@muktaa

3. GOAL
@muktaa
•git push
•Triggers
build
Code
Generate
Docker
Image
Build
Process
Save Image
Docker
Image
Unique Tag
Docker
Registry
•docker pull
•docker
stop
•docker run
Deploy

4. EXAMPLE
• git push to https://github.com/muktaa/HelloScala
• Triggers a build on your CI server
• sbt docker
• docker push muktaa/hello-scala
• Deploy
• Build tools offer docker integration
• Eg: Maven has docker-maven-plugin
• https://github.com/spotify/docker-maven-plugin
• mvn clean package docker:build -DpushImage

5. ~/github/HelloScala > sbt docker
[info] Loading project definition from
/Users/muktaaphale/github/HelloScala/project
[info] Set current project to hello-scala (in build
file:/Users/muktaaphale/github/HelloScala/)
[info] Creating docker image with name: 'muktaa/hello-scala'
:
[info] Sending build context to Docker daemon
[info] Step 0 : FROM dockerfile/java
[info] ---> 1126c85d8a06
[info] Step 1 : ADD /app/hello-scala_2.11-1.4-one-jar.jar /app/hello-scala_2.11-
1.4-one-jar.jar
[info] ---> Using cache
[info] ---> 61871958f108
[info] Step 2 : ENTRYPOINT java -jar /app/hello-scala_2.11-1.4-one-jar.jar
[info] ---> Using cache
[info] ---> a8005b32ddc4
[info] Successfully built a8005b32ddc4
[info] Successfully built Docker image: muktaa/hello-scala
[success] Total time: 1 s, completed Mar 3, 2015 2:10:04 PM
~/github/HelloScala > docker images | grep hello-scala
muktaa/hello-scala latest a8005b32ddc4 12 hours ago 715 MB
~/github/HelloScala > docker run muktaa/hello-scala
Hello, world! #1
Hello, world! #2
Hello, world! #3

6. DOCKER REGISTRY
Docker Hub
Link: https://registry.hub.docker.com/u/muktaa/hello-
scala
Automated Build in Docker:
https://registry.hub.docker.com/u/muktaa/helloscala-
automated-build/

7. CHALLENGES
• Docker based CI server (Travis-CI)
• Tight coupling with build tool
• Base Image
• Monitoring
• Debugging
• Handling configuration for various environments
• Secure Credential Management
@muktaa

8. LESSONS LEARNT
• Running apps in containers is easy
• Debugging apps in containers is difficult
• You can very well run multiple services inside a docker
container
• Ah the woes of Docker networking!
• Sequential Progression
@muktaa

9. CONFIGURATION MANAGEMENT VS DOCKER
• Control the environment Vs System Image / Runtime
image
• Tradeoff between flexibility and convenience
• CM is the vein of DevOps
• Shell scripts -> Chef
• Immutable Infrastructure
@muktaa

10. DOCKER AND ANSIBLE
@muktaa

11. ANSIBLE
• Ansible Tower
• Playbooks
• Ansible Tower API
@muktaa
•git push
•Triggers
build
Code
Generate
Docker
Image
Build
Process
Save Image
Docker
Image
Unique Tag
Docker
Registry
•docker pull
•docker stop
•docker run
Deploy

12. ANSIBLE TOWER API
• http://www.ansible.com/tower
• Dashboard
• Job handling and scheduling ease
• Rest API
• Tower CLI
@muktaa

13. ANSIBLE TOWER CLI
• https://github.com/ansible/tower-cli
• Configure
• $ tower-cli config host tower.example.com
• $ tower-cli config username mukta
• $ tower-cli config password password
• Launch a job.
• $ tower-cli job launch --job-template=144
@muktaa

14. ANSIBLE PLAYBOOK
- name: pull latest repo
command: docker pull muktaa/hello-scala
- name: Stop existing container
shell: docker ps | grep 8585 | awk -F" " '{print $1}'
register: result
ignore_errors: true
@muktaa

15. ANSIBLE PLAYBOOK
- name: Run new docker image
command: docker run -d -i -t --privileged -p 8585:8585 -h={{
ansible_hostname }} muktaa/hello-scala -DCLUSTER_IP={{ ansible_hostname }} -
Dcom.sun.management.jmxremote.port=9999 -
Dcom.sun.management.jmxremote.authenticate=false -
Dcom.sun.management.jmxremote.ssl=false -DSEED_HOST={{ ansible_seed }}
register: result
ignore_errors: true
@muktaa

16. ANSIBLE DOCKER MODULE
- name: akka seed container
docker:
name: seed
image: muktaa/hello-scala
state: started
expose:
- 8585
volumes_from:
- mydata
env:
SECRET_KEY: xyz
@muktaa

17. DOCKER AND CHEF
@muktaa

18. DOCKER COOKBOOK
• Available in Supermarket: https://supermarket.chef.io/cookbooks/docker
• Install docker
• Build docker image
• Pull image and run container
• Push docker image to registry
• LWRPs
• Docker_container
• Docker_image
• Docker_registry
• https://github.com/bflad/chef-docker/blob/master/README.md

19. CREDENTIAL MANAGEMENT
secret =
Chef::EncryptedDataBagItem.load_secret
@docker_cred =
Chef::EncryptedDataBagItem.load(
node['docker']['creds']['databag'],
node['docker']['user'],
secret
)
docker_registry
‘https://registry.hub.docker.com/u/muktaa/he
llo-scala/’ do
email docker_cred['email']
username docker_cred['username']
password docker_cred['password']
end

20. DOCKER_IMAGE
# Build a docker image using docker_image
resource
docker_image node['docker']['image'] do
tag node['docker']['image']['tag']
source '/var/docker'
action :build
end
# Push the image to docker registery
docker_image node['docker']['image'] do
action :push
end
# Delete the image from the machine
docker_image node['docker']['image'] do
action :remove
end

21. DOCKER_CONTAINER
# Run Container
docker_container ‘muktaa/hello-scala’
detach true
port ‘8081:8081’, ‘8085:8085’
env ‘ENVIRONMENT=pre-prod’
volume ‘/mnt/docker/docker-storage’
action :run
end

22. GENERATE DOCKERFILE
# Generate a docker file using template.
template "#{node['docker']['directory']}/Dockerfile" do
source 'dockerfile.erb'
variables image: node['docker']['base']['image']['name'],
maintainer: @docker_cred['maintainer'],
email: docker_cred['email'],
build_cmd: node['docker']['build']['commands'],
entry_point: node['docker']['build']['entry_point']
action :create
end

23. WORKFLOW
Build
Application
• Save the Artifact to a Repository
Manager
Build Docker
Image
• Docker cookbook would build and save the
docker image
Deploy
• Docker cookbook runs the
container on the nodes

24. CHEF CONTAINERS
• Package
• Provides Configuration Management for
containers

25. CHEF CONTAINER COMPONENTS
chef-client
runit
chef-init

26. WHY CHEF CONTAINERS?
• Bootstrap chef-client without SSH connection
• Manage multiple services inside your
container
• Manage running state of your container
• Consistency across Architectures
• Mixed Architecture Applications

27. BEST SUITED FOR
• Transitioning traditional architecture to containers
• Handling last mile configuration when container boots
• Getting the best of two worlds without complexity

28. KNIFE CONTAINER DOCKER INIT
• Gem install knife-container
• knife container docker init NAMESPACE/IMAGE_NAME
[options]
• -f base docker image (default is ubuntu 12.04) - chef container
should be already installed on it
• -r runlist
• -z chef client local mode
• -b use berkshelf

29. EXAMPLE
$ sudo knife container docker init muktaa/hello-scala-cc
Compiling Cookbooks...
Recipe: knife_container::docker_init
* directory[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc] action create
* template[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/Dockerfile] action
create
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/Dockerfile from none to 943017
- * template[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/.dockerignore]
action create
- create new file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/.dockerignore
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/.dockerignore from none to e3b0c4
* directory[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef] action create
- create new directory /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef
* template[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/client.rb] action
create
- create new file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/client.rb
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/client.rb from none to 7de61f
* file[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/first-boot.json] action
create
- create new file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/first-
boot.json
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/first-boot.json from none to 5269ef
* template[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/.node_name]
action create
- create new file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/.node_name
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/.node_name from none to 4764d2
* template[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/Berksfile] action
create (skipped due to only_if)
* directory[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc/chef/secure] action
create
- create new directory /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/secure
* file[/home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/secure/validation.pem] action create
- create new file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/secure/validation.pem
- update content in file /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-
cc/chef/secure/validation.pem from none to ec1f3e
- change mode from '' to '0600'
Downloading base image: chef/ubuntu-12.04:latest. This process may take awhile...
Tagging base image chef/ubuntu-12.04 as muktaa/hello-scala-cc
Context Created: /home/ubuntu/chef-repo/dockerfiles/muktaa/hello-scala-cc

30. KNIFE CONTAINER DOCKER BUILD
• run command docker images
• knife container docker build
• resolve docker dependencies
• build docker image
• cleanup chef artifacts

31. EXAMPLE
$ sudo knife container docker build muktaa/hello-scala-cc
Sending build context to Docker daemon 9.728 kB
Sending build context to Docker daemon
Step 0 : FROM muktaa/hello-scala-cc
---> 50d3c5c9e133
Step 1 : ADD chef/ /etc/chef/
---> 4933cc9e13e0
Removing intermediate container da0a08413a91
Step 2 : RUN chef-init --bootstrap
---> Running in add27db609cc
[2015-03-31T21:44:44+00:00] INFO: Starting Supervisor...
[2015-03-31T21:44:44+00:00] INFO: Supervisor pid: 9
[2015-03-31T21:44:49+00:00] INFO: Starting chef-client run...
[2015-03-31T21:44:50+00:00] INFO: Forking chef instance to converge...
[2015-03-31T21:44:50+00:00] INFO: *** Chef 11.16.2 ***
[2015-03-31T21:44:50+00:00] INFO: Chef-client pid: 16
[2015-03-31T21:44:53+00:00] INFO: Client key /etc/chef/secure/client.pem is not present - registering
[2015-03-31T21:44:53+00:00] INFO: HTTP Request Returned 404 Object Not Found: error
[2015-03-31T21:44:54+00:00] INFO: Setting the run_list to [] from CLI options
[2015-03-31T21:44:54+00:00] INFO: Run List is []
[2015-03-31T21:44:54+00:00] INFO: Run List expands to []
[2015-03-31T21:44:54+00:00] INFO: Starting Chef Run for muktaa-hello-scala-cc-build
[2015-03-31T21:44:54+00:00] INFO: Running start handlers
[2015-03-31T21:44:54+00:00] INFO: Start handlers complete.
[2015-03-31T21:44:55+00:00] INFO: Loading cookbooks []
[2015-03-31T21:44:55+00:00] WARN: Node muktaa-hello-scala-cc-build has an empty run list.
[2015-03-31T21:44:55+00:00] INFO: Chef Run complete in 1.121705004 seconds
[2015-03-31T21:44:55+00:00] INFO: Running report handlers
[2015-03-31T21:44:55+00:00] INFO: Report handlers complete
[2015-03-31T21:44:55+00:00] INFO: Sending resource update report (run-id: 6f637baf-18cc-4620-b3e2-
9afc90e8cd6b)
---> 2c2ec6fab1ef
Removing intermediate container add27db609cc
Step 3 : RUN rm -rf /etc/chef/secure/*
---> Running in 30a3611b083f
---> cab28d6eed90
Removing intermediate container 30a3611b083f
Step 4 : ENTRYPOINT ["chef-init"]
---> Running in 0a9f4e96bbf7
---> a8577b66b103
Removing intermediate container 0a9f4e96bbf7
Step 5 : CMD ["--onboot"]
---> Running in f9a444817229
---> 21b3800bc9b3
Removing intermediate container f9a444817229
Successfully built 21b3800bc9b3

32. DOCKER IMAGES
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
muktaa/hello-scala-cc latest 21b3800bc9b3 2 hours ago 311.9 MB
<none> <none> b343c8301cc8 2 hours ago 311.9 MB
chef/ubuntu-12.04 latest 50d3c5c9e133 6 months ago 311.9 MB
$ sudo docker push muktaa/hello-scala-cc
$ sudo docker –d run muktaa/hello-scala-cc

33. THANK YOU!
@muktaa