Ansible Tips And Tricks

Florian Dambrine

July 8th 2015

Los Angeles Ansible Meetup Group

@DambrineF

Hashtag for the event: #GumGumAnsible

whoami

  • Florian Dambrine

  • DevOps Engineer - Big Data Team - GumGum

  • Born and raised in France

  • Joined GumGum 15 months ago

  • About a year of experience with Ansible

  • Invented In-Image advertising in 2008 
    http://gumgum.com/gallery

     
  • 10x the engagement of traditional display ads
     
  • 2,000+ premium publishers
     
  • 350MM unique visitors per month
     
  • Major US advertiser adoption
     
  • 200% revenue growth in 2014
     
  • 100 employees in six offices

Agenda

  • General facts about Ansible
    • What is Ansible?
    • Configuration management Communities
    • Terminology
  • Tips and Tricks with Ansible
    • Best Practices
    • Tricks
  • Q/A

Introduction

Years ago, Bash was used to automate repeated tasks...

Later on, configuration management tools appeared...

Today...

ANSIBLE

> What is Ansible?

  • Open source project started by Michael DeHaan in Feb. 2012
  • Automation engine written in Python
  • Used as :
    • Configuration Management tool
    • Orchestration tool
    • Application deployment tool
  • Push based (Can do pull too)
  • inventory : Against what you are running your automations?

ANSIBLE - TERMINOLOGY

Static Inventory

Dynamic Inventory

### INI file format

[dbservers]
db-prod.meetup.com
db-test.meetup.com

[webservers]
foo.meetup.com
bar.meetup.com

...

ANSIBLE - TERMINOLOGY

  • fact : System information that can be discovered from a system
{
...
    "ansible_eth0": {
        "active": true,
        "device": "eth0",
        "ipv4": {
            "address": "REDACTED",
            "netmask": "255.255.255.0",
            "network": "REDACTED"
        },
        ...
    },
    "ansible_kernel": "3.5.0-23-generic",
    "ansible_lsb": {
        "codename": "precise",
        "description": "Ubuntu 12.04.2 LTS",
        "id": "Ubuntu",
        "major_release": "12",
        "release": "12.04"
    },
    "ansible_machine": "x86_64",
...
}

ANSIBLE - TERMINOLOGY

  • module : Abstraction of a task

Linux commands

apt

Ansible modules

apt

ln

mkdir

touch

  ------------------------------>

---------------|

---------------|-------------->

                           |

files

                           |

---------------|

ANSIBLE - TERMINOLOGY

  • task : Run an action from a module with specified arguments 

It is possible to leave off the ‘name’ for a given task, though it is recommended to provide a description about why something is being done instead. This name is shown when the playbook is run.

---
- name: Install Nginx
  apt: 
    name: nginx 
    update_cache: yes 
    state: present
---
- name: Create the scripts log folder 
  file: 
    state: directory
    path: /var/log/gumgum-scripts
    owner: gumgum
    group: gumgum
    mode: 644
---
- name: Start an EC2 instance
  local_action: 
    module: ec2
    aws_access_key: 'AKIAXXXXXXXXX'
    aws_secret_key: 'XXXXXXXXXXXXX'
    key_name: 'mykeypair.pem'
    instance_type: 'c3.large'
    wait: yes
    image: 'ami-XXXXXX'
    count: 1
    region: 'us-east-1'
    zone: 'us-east-1b'
    monitoring: yes
    group: ['sshonly', 'webapp']
    instance_tags: 
      Name: demo
      Owner: 'Florian Dambrine'
    volumes: 
      - device_name: /dev/sda1
        volume_size: 30

ok

changed

skipped

failed

Return codes of a task

ANSIBLE - TERMINOLOGY

  • play : What tasks to play on what servers

Example with an ad-hoc command

$ ansible webservers -s -m apt -a "name=nginx state=latest update_cache=yes"
foo.meetup.com | success >> {
    "changed": true, 
    "stderr": "", 
    "stdout": "Reading package lists...\nBuilding dependency tree...\nReading state......"
}
bar.meetup.com | success >> {

Example with the ansible-playbook command

### nginx-play.yaml
---
- hosts: webservers
  sudo: yes
  tasks:
    - name: Install Nginx
      apt: 
        name: nginx 
        update_cache: yes 
        state: present
$ ansible-playbook nginx-play.yaml

PLAY [webserver] *************************************

TASK: [Install Nginx] ********************************
changed: [foo.meetup.com]
changed: [bar.meetup.com]

PLAY RECAP *******************************************
foo.meetup.com : ok=0 changed=1 unreachable=0 failed=0   
bar.meetup.com : ok=0 changed=1 unreachable=0 failed=0   

ANSIBLE - TERMINOLOGY

  • playbook : A list of plays
### nginx-playbook.yaml
---
- hosts: webservers
  sudo: yes
  tasks:
    - name: Install Nginx
      apt: 
        name: nginx
        state: latest
        update_cache: yes

    - name: Cleaning apps-enabled
      file: 
        state: absent 
        path: /etc/nginx/sites-enabled/default
    
    - name: Cleaning apps-available
      file: 
        state: absent 
        path: /etc/nginx/sites-available/default

    - name: Restart Nginx
      service:
        name: nginx
        state: restarted

receipe

manifest

ANSIBLE - TERMINOLOGY

  • roles : Reusable self-contained entity
rolename/
├── defaults/        ---> Lowest priority variables.
│   └── main.yaml
├── files/           ---> Contains static files that need to be deployed on remote server.
│   └── ...               
├── handlers/        ---> Contains tasks that can be triggered by a notification event.
│   └── main.yaml         
├── meta/            ---> Contains dependencies between roles.
│   └── main.yaml
├── tasks/           ---> Contains your soup.
│   ├── ...
│   ├── main.yaml
├── templates/       ---> Contains templates that will be fed with variables (facts, or role vars).
│   ├── ....j2            
├── vars/            ---> Higher level of priority where default variables will be overriden.
│   ├── ...               
│   ├── main.yaml
--------------------
└── vagrant/         ---> Vagrant testing environment
    ├── ansible.cfg
    ├── rolename.yaml
    └── Vagrantfile

cookbook

module

GUMGUM Before Ansible...

What we used to do a year ago....

cookbooks

AWS S3

AWS EC2 instances

  • Use of Chef-Solo and EC2 User Data

2

1

3

4

upload

download at bootstrap

Python / Boto for Kickoff

Why was this process Painful?

Drawbacks:

  • Tedious release process: packaging - upload to S3 - update the latest version...
     
  • Instance automated thanks to a bootstrap script, what happens when the instance is live?
     
  • When it breaks how do you fix it? How do you get notified when it's done?
     
  • Usage of an additional tool (Python) to spin up instances.

THIS IS NOT AUTOMATION!

First steps with Ansible...

---
- hosts: cassandra
  serial: 1
  sudo: yes

  tasks:
  - name: Edit cassandra-env.sh
    copy: 
      src: cassandra-env.sh 
      dest: /etc/cassandra/cassandra-env.sh 
      backup: yes 
      owner: root 
      group: opscenter-admin 
      mode:664

  - name: Restart Cassandra
    service: 
      name: cassandra 
      state: restarted

  - name: Wait for the node to join the cluster back
    shell: sleep 300
  • Tuning parameters on a 25 node Cassandra cluster

Ansible today at gumgum

$ ls ~/workspace/ops/ansible/roles
ansible    elasticsearch       icinga           mysql             ruby
autopull   fluentd             icinga2          nagios            sails
aws-cli    forecasting-server  insights-api     nginx             spark
baseline   ganglia             java             nodejs            spiderami
bower      ganglia-server      jenkins          opscenter         squid
cassandra  gradle              kafka            php               storm
common     graphite            kibana           play-mantii       tomcat
cron       groovy              logo-server      postfix-client    ui-proxy
django     grunt               logstash-client  postfix-relay     uptime
druid      gumgum-adbuilder    logstash-parser  raid0             uwsgi
ec2        gumgum-realtime     mongodb          reporting-server  zookeeper
ec2-ami    gumgum-web          monitoring       role-skel
  • About 60 roles including cluster automations
  • Managing 4 AWS accounts  (Mix of VPC and EC2Classic) with the same ansible repository.
  • Ansible is dealing with 500 servers everyday.
  • Provision and Automation with Ansible

Why do WE love ansible?

  • Interactive automation process
  • Fast learning curve
  • Cool features:
    • --start-at-task
    • --list-tasks
    • --list-hosts
    • --step
    • --syntax-check

Tips And tricks

USe DEDICATED MODULES instead of shell

Ansible provides ~320 modules that can control system resources

Try to build idempotent roles

$> Two ways of doing the same thing...

---
- hosts: all
  sudo: yes
  vars:
    version: '2.4.2'
    url: http://dl.bintray.com/groovy/maven
  tasks:
    - name: Install dependencies
      shell: "apt-get update && apt-get -y install unzip openjdk-7-jdk"

    - name: Download Groovy
      shell: "wget -q -O /tmp/groovy-{{ version }}.zip {{ url }}/groovy-binary-{{ version }}.zip"

    - name: Extract Groovy archive
      shell: "unzip -u /tmp/groovy-{{ version }}.zip -d /opt"

    - name: Export JAVA_HOME in profile.d
      shell: "echo JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-amd64 > /etc/profile.d/groovy-env.sh"

    - name: Export GROOVY_HOME in profile.d
      shell: "echo GROOVY_HOME=/opt/groovy-{{ version }} >> /etc/profile.d/groovy-env.sh"

    - name: Setup the PATH in profile.d
      shell: "echo PATH=$PATH:/usr/lib/jvm/java-1.7.0-openjdk-amd64/bin:/opt/groovy-{{ version }}/bin >> \
        /etc/profile.d/groovy-env.sh"

    - name: Run Groovy version
      shell: "groovy -v"
      environment:
        PATH: "{{ ansible_env.PATH }}:/opt/groovy-{{ version }}/bin"
      register: groovy_version

    - debug:
        var: groovy_version.stdout
  • Shell style:
  • Ansible style:
---
- hosts: all
  sudo: yes
  vars:
    version: '2.4.2'
    url: 'http://dl.bintray.com/groovy/maven'
  tasks:
    - name: Install dependencies
      apt: "name={{ item }} update_cache=yes"
      with_items: ['unzip', 'openjdk-7-jdk']

    - name: Download Groovy
      get_url:
        url: "{{ url }}/groovy-binary-{{ version }}.zip"
        dest: "/tmp/groovy-{{ version }}.zip"

    - name: Extract Groovy archive
      unarchive:
        src: "/tmp/groovy-{{ version }}.zip"
        dest: "/opt"
        creates: "/opt/groovy-{{ version }}"
        copy: no

    - name: Deploy groovy-env in profile.d
      template:
        src: groovy-env.sh.j2
        dest: '/etc/profile.d/groovy-env.sh'

    - name: Run Groovy version
      shell: "groovy -v"
      environment:
        PATH: "{{ ansible_env.PATH }}:/opt/groovy-{{ version }}/bin"
      changed_when: false
      register: groovy_version

    - debug:
        var: groovy_version.stdout
JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk-amd64
GROOVY_HOME=/opt/groovy-{{ version }}
PATH=$PATH:/usr/lib/jvm/java-1.7.0-openjdk-amd64/bin:/opt/groovy-{{ version }}/bin

groovy-env.sh.j2

This playbook is idempotent and leverages:

  • modules
  • templates
PLAY [all] ********************************** 

GATHERING FACTS *****************************
ok: [instance-1]

TASK: [Install dependencies] **************** 
changed: [instance-1]

TASK: [Download Groovy] *********************
changed: [instance-1]

TASK: [Extract Groovy archive] **************
changed: [instance-1]

TASK: [Export JAVA_HOME in profile.d] *******
changed: [instance-1]

TASK: [Export GROOVY_HOME in profile.d] *****
changed: [instance-1]

TASK: [Setup the PATH in profile.d] *********
changed: [instance-1]

TASK: [Run Groovy version] ******************
changed: [instance-1]

TASK: [debug ] ******************************
ok: [instance-1] => {
    "var": {
        "groovy_version.stdout": "Groovy Version: 2.4.2"
    }
}

PLAY RECAP **********************************
instance-1:
    ok=9    
    changed=7    
    unreachable=0    
    failed=0   
PLAY [all] **********************************

GATHERING FACTS *****************************
ok: [instance-1]

TASK: [Install dependencies] ***************** 
ok: [instance-1] => (item=unzip,openjdk-7-jdk)

TASK: [Download Groovy] **********************
ok: [instance-1]

TASK: [Extract Groovy archive] *************** 
ok: [instance-1]

TASK: [Deploy groovy-env in profile.d] ******* 
ok: [instance-1]

TASK: [Run Groovy version] ******************* 
ok: [instance-1]

TASK: [debug ] ******************************* 
ok: [instance-1] => {
    "var": {
        "groovy_version.stdout": "Groovy Version: 2.4.2"
    }
}







PLAY RECAP ***********************************
instance-1                 
    ok=7    
    changed=0    
    unreachable=0    
    failed=0   

Shell style play

Ansible style play

Default your role's variables

  • By defaulting your role, you make it:
    • Usable right away
    • Flexible
default variables are the most "defaulty" variables and they lose in priority to everything
# This file includes Java default variables
---
  # Override this variable if you need to 
  # switch from java 7 to 8
  java_default_version: 7
  
  # S3 bucket from where the JDK will be downloaded
  java_jdk_bucket: ansible
  java_jdk_bucket_path: distribution/jdk

  # List of jdk to deploy (needs to be in the S3 bucket)
  java_versions:
    - jdk1.7.0_80
    - jdk1.8.0_45

  # Aliases will be build as following:
  # java-X-oracle -> jdk1.X.y_zz
  # java-7-oracle -> jdk1.7.0_80
  java_aliased_versions:
    - jdk1.7.0_80
    - jdk1.8.0_45

  # Where the .tar.gz will be dropped
  java_download_folder: /tmp

  # Where the JDK will be installed
  java_root_folder: /opt
ansible/ ### Ansible Repository Structure
├── java.yaml
│
└── roles/java/
    └── defaults/
        └── main.yaml
florian@instance-1:/opt$ ls
java-7-oracle@  java-8-oracle@  jdk1.7.0_80  jdk1.8.0_45
florian@instance-1:/etc/profile.d$ cat java-env.sh 
#!/bin/bash

export JAVA_HOME=/opt/java-7-oracle
export PATH=$PATH:$JAVA_HOME/bin
  • Default role behavior:
florian@instance-2:/usr/lib/jvm$ ls
java-7-oracle@  java-8-oracle@  jdk1.7.0_80  jdk1.8.0_45
  • Role used with the override.json file:
florian@instance-2:/etc/profile.d$ cat java-env.sh 
#!/bin/bash

export JAVA_HOME=/usr/lib/jvm/java-8-oracle
export PATH=$PATH:$JAVA_HOME/bin
ansible-playbook java.yaml \
    --limit webservers \
    --extra-vars "@override_java"
##################################
### Create a variable file

vim override_java.json

##################################
### Override default behavior
---
  java_default_version: 8
  java_root_folder: /usr/lib/jvm
  • Change role's behavior:

$> Example

manage multiple accounts using the same ansible repository

Lookup plugins allow access of data in Ansible from outside sources (files, ENV vars)

---
  aws_credentials_key_id: 'AKIA123456789'
  aws_credentials_secret_key: '...'

  ec2_image: ami-76b2a71e

  ec2_region: us-east-1

  ec2_az:
    - us-east-1a
    - us-east-1b
    - us-east-1c
    - us-east-1d
    - us-east-1e

  ec2_count:
    - 0 # How many in us-east-1a ?
    - 1 # How many in us-east-1b ?
    - 0 # How many in us-east-1c ?
    - 0 # How many in us-east-1d ?
    - 0 # How many in us-east-1e ?

  ec2_key: keypair-1

  ec2_sg: va-ops
---
  aws_credentials_key_id: 'AKIAABCDEFGHI'
  aws_credentials_secret_key: '...'

  ec2_image: ami-b97a12ce

  ec2_region: eu-west-1

  ec2_az:
    - eu-west-1a
    - eu-west-1b
    - eu-west-1c

  ec2_count:
    - 0 # How many in eu-west-1a ?
    - 1 # How many in eu-west-1b ?
    - 0 # How many in eu-west-1c ?

  ec2_vpc_subnet:
   - undefined
   - subnet-56b01521
   - undefined

  ec2_key: keypair-2

  ec2_sg: ie-ops

roles/ec2/vars/virginia/ec2.yaml

roles/ec2/vars/ireland/ec2.yaml

$> Content of the variable files

$> usage of the Lookup in the playbook

- hosts: 127.0.0.1
  sudo: yes

  vars_files:

    # Load EC2 account vars
    - "roles/ec2/vars/{{ lookup('env','AWS_ACCOUNT') }}/provision.yaml"

  roles:
    - { role: ec2, tags: ['provision'] }
- hosts: 127.0.0.1
  sudo: yes
  
  vars:
    instance: elasticsearch
  vars_files:
    # Load EC2 account vars
    - "roles/ec2/vars/{{ lookup('env','AWS_ACCOUNT') }}/{{ instance }}-provision.yaml"
  roles:
    - { role: ec2, tags: ['provision'] }
florian@instance-1$ ls ansible/roles/ec2/vars/virginia/
elasticsearch-provision.yaml
cassandra-provision.yaml
cron-provision.yaml
nginx-provision.yaml
...

---------------------------------------------------------

keep Track of your instances as you track their configuration

Ansible provides cloud modules that allows you to interact with your cloud instances.

Use case:

June 2014, the DevOps team started a 25 node Cassandra cluster:

  • r3.2xlarge with 60G Memory
  • 4 EBS Volumes (SSDs) 150G each
  • Optimized bandwidth for EBS

------------

In March 2015, 3 instances are scheduled for retirement by AWS because of running on degraded hardware...

 

Do you remember how you started your instances a year ago?

$> solving your issue with the lookup plugin

- hosts: 127.0.0.1
  sudo: yes
  
  vars:
    instance: elasticsearch
  vars_files:
    # If the first file exists use it, otherwise fallback to default
    - [
        "roles/ec2/vars/{{ lookup('env','AWS_ACCOUNT') }}/{{ instance }}-{{ lookup('env','INSTANCE_ID') }}.yaml",
        "roles/ec2/vars/{{ lookup('env','AWS_ACCOUNT') }}/{{ instance }}-provision.yaml"
      ]

  roles:
    - { role: ec2, tags: ['provision'] }
florian@instance-1$ ls ansible/roles/ec2/vars/virginia/
cassandra-provision.yaml
cassandra-realtime.yaml
cassandra-analytics.yaml
...
elasticsearch-provision.yaml
elasticsearch-logstash.yaml
elasticsearch-main.yaml
elasticsearch-test.yaml
...

improve teamwork and code review

  • Code review and PR also applies to configuration management

    Tips:
     
  • Keep your files under 100 lines
     
  • Break things into pieces

$> WHAT we USED TO DO...

---
  - name: Adding Elasticsearch public GPG key
    shell: wget -O - http://packages.elasticsearch.org/GPG-KEY-elasticsearch | apt-key add -

  - name: Adding Elasticsearch source.list.d
    apt_repository: "repo='deb http://packages.elasticsearch.org/elasticsearch/{{ elasticsearch_version }}/debian stable main' state=present"

  - name: Install Elasticsearch
    apt: "update_cache=yes name=elasticsearch={{ elasticsearch_version }}"

  - name: Deploy the elasticsearch.yml configuration file
    template: "src=elasticsearch.yml.j2 dest={{ elasticsearch_config_folder }}/elasticsearch.yml owner=root group=root mode=0744"

  - name: Deploy default configuration used by the startup script
    template: src=elasticsearch-default.j2 dest=/etc/default/elasticsearch owner=root group=root mode=0644
    tags: configuration
  • Tasks become harder to understand
  • Hard to figure out how to properly quote a task

$> WHAT we are doing now

---
  - name: Adding Elasticsearch public GPG key
    shell: wget -O - http://packages.elasticsearch.org/GPG-KEY-elasticsearch | apt-key add -

  - name: Adding Elasticsearch source.list.d
    apt_repository: 
      repo: "deb http://packages.elasticsearch.org/elasticsearch/{{ elasticsearch_version }}/debian stable main"
      state: present

  - name: Install Elasticsearch
    apt: 
      update_cache: yes 
      name: "elasticsearch={{ elasticsearch_version }}"

  - name: Deploy the elasticsearch.yml configuration file
    template: 
      src: elasticsearch.yml.j2 
      dest: "{{ elasticsearch_config_folder }}/elasticsearch.yml"
      owner: root 
      group: root 
      mode: 0744 #--------------------------> Change introduced here

  - name: Deploy default configuration used by the startup script
    template: 
      src: elasticsearch-default.j2 
      dest: /etc/default/elasticsearch 
      owner: root 
      group: root 
      mode: 0644
  • Easier to read long tasks
  • Easier to review your PR

Make your 

templates flexible

  • Flexible templates, Flexible automations!
  • Feel free to enable Jinja extensions

Feedback: Especially with technologies like Cassandra or Elasticsearch, new versions come with new settings ...

### /etc/ansible/ansible.cfg
...
# list any Jinja2 extensions:
jinja2_extensions = jinja2.ext.do
...
---
- hosts: all
  sudo: yes
  vars:
    ec2_tags:
      Name: 'webserver-instance'
      Owner: 'Unkown-owner'
      AnsibleId: 'webserver'

    ec2_extra_tags:
      Owner: 'Florian Dambrine'
  tasks:
    - name: Merge the two EC2 tag dictionaries
      local_action:
        module: set_fact
        ec2_tags: "{% do ec2_tags.update(ec2_extra_tags) %}{{ ec2_tags }}"

    - debug:
        var: ec2_tags
TASK: [Merge the two EC2 tag dictionaries]
ok: [instance-1 -> 127.0.0.1]

TASK: [debug ] ***************************
ok: [instance-1] => {
    "var": {
        "ec2_tags": {
            "AnsibleId": "webserver", 
            "Name": "webserver-instance", 
            "Owner": "Florian Dambrine"
        }
    }
}

erb

erb

$> WHAT we used to do...

################################### Cluster ###################################

# Cluster name identifies your cluster for auto-discovery. If you're running
# multiple clusters on the same network, make sure you're using unique names.
#
cluster.name: {{ elasticsearch_cluster_name }}

################################## Logstash optimizations ####################

#Tunning performances for restarts

cluster.routing.allocation.node_initial_primaries_recoveries: {{ elasticsearch_cluster_routing_allocation_node_initial_primaries_recoveries }}
cluster.routing.allocation.node_concurrent_recoveries: {{ elasticsearch_cluster_routing_allocation_node_concurrent_recoveries }}
indices.recovery.max_bytes_per_sec: {{ elasticsearch_indices_recovery_max_bytes_per_sec }}
indices.recovery.concurrent_streams:  {{ elasticsearch_indices_recovery_concurrent_streams }}
...
---
  elasticsearch_cluster_routing_allocation_node_initial_primaries_recoveries: 4
  elasticsearch_cluster_routing_allocation_node_concurrent_recoveries: 8

  elasticsearch_indices_recovery_max_bytes_per_sec: 100mb
  elasticsearch_indices_recovery_concurrent_streams: 5

templates/elasticsearch.yaml.j2

vars/elasticsearch-logstash.yaml

$> What we are doing now

###
### elaticsearch.yaml configuration file
###
{% set elasticsearch_yaml_sorted = elasticsearch_yaml | dictsort() %}

{% for key, val in elasticsearch_yaml_sorted %}
{{ key }}: "{{ val }}"
{% endfor %}
---
elasticsearch_yaml: {
  'cluster.name': "logstash",

  'routing.allocation.node_initial_primaries_recoveries': 4,
  'routing.allocation.node_concurrent_recoveries': 8,
 
  'discovery.zen.ping.multicast.enabled': 'false'
}
  • Use jinja loops to render your files.
  • Do not be afraid of new releases anymore!

templates/elasticsearch.yaml.j2

vars/elasticsearch-logstash.yaml

cluster.name: "logstash"
discovery.zen.ping.multicast.enabled: 'false'
routing.allocation.node_concurrent_recoveries: 8
routing.allocation.node_initial_primaries_recoveries: 4

Output

Pick one way to define dependencies

  • The meta/main.yaml file inside a role allows you to define the role dependencies.
     
  • Am I going to break dozens of automations if I update the java role used by all of them?
---
  dependencies:
    - role: common
      tags: ['common']

    - role: nginx
      tags: ['nginx']

    - role: php
      tags: ['php']

    - role: aws-cli
      tags: ['aws-cli']

    - role: mysql
      tags: ['mysql']

    - role: graphite
      tags: ['graphite']

icinga2/meta/main.yaml

$> What we used to do...

$> What we Are doing now...

- hosts: all
  sudo: yes

  roles:
    # Configuration part
    - { role: common, tags: ['common', 'logstash-client'] }
    - { role: java, tags: ['java', 'logstash-client'] }
    - { role: logstash-client, tags: ['logstash-client'] }

    # Monitoring part
    - { role: nagios, tags: ['nagios', 'logstash-client'] }
    - { role: icinga2-reload, tags: ['icinga2-reload', 'logstash-client'] }
  • Wrap your dependencies in the playbook
     
  • Makes your dependencies explicit

logstash-client-playbook.yaml

Version your roles

  • While doing a major refactoring on a role, it might be a good idea to copy it as a new version in order to avoid breaking "legacy" systems.
     
  • Legacy roles can go away when  everything has moved to the newest versions.
     
  • Track your latest
    roles.

     
  • Versioning becomes
    easier without meta.

$> DROP a readme.md and track the changes

$> Versioning roles implies versionING playbooks...

florian~/ansible/roles$ ls -1 | grep java

java        ---> Legacy Java version
java-001    ---> Latest Java role
- hosts: all
  sudo: yes

  roles:
    # Configuration part
    - { role: common, tags: ['common', 'logstash-client'] }
    - { role: java, tags: ['java', 'logstash-client'] }
    - { role: logstash-client, tags: ['logstash-client'] }

    # Monitoring part
    - { role: nagios, tags: ['nagios', 'logstash-client'] }
    - { role: icinga2-reload, tags: ['icinga2-reload', 'logstash-client'] }

logstash-client-playbook.yaml

- hosts: all
  sudo: yes

  roles:
    # Configuration part
    - { role: common, tags: ['common', 'logstash-client'] }
    - { role: java-001, tags: ['java', 'logstash-client'] }
    - { role: logstash-client, tags: ['logstash-client'] }

    # Monitoring part
    - { role: nagios, tags: ['nagios', 'logstash-client'] }
    - { role: icinga2-reload, tags: ['icinga2-reload', 'logstash-client'] }

logstash-client-001-playbook.yaml

000

001

Build smart playbooks using tags

  • At GumGum, our playbooks contain the following steps:
    • EC2 Provision
    • Automation
    • Testing
    • Cleanup
    • EC2 AMI Build
    • Test the previously
      built EC2 AMI

$> Use consistent tagging across your playbooks

######################################################################
### Full stack play from provision to AMI

- hosts: 127.0.0.1
  sudo: yes
  vars:
    - instance: forecasting-server
  roles:
    - { role: ec2-001, tags: ['provision'] }

- hosts: all
  sudo: yes
  vars:
    - instance: forecasting-server
    - ami_prefix_name: "{{ instance }}"
  roles:
    # Playbook dependencies
    - { role: common-001, tags: ['configure', 'test', 'cleanup', 'create-ami', 'test-ami'] }
    - { role: java-001, tags: ['configure', 'test', 'cleanup', 'create-ami', 'test-ami'] }
    - { role: groovy-001, tags: ['configure', 'test', 'cleanup', 'create-ami', 'test-ami'] }

    # Main Role that can be called with 'configure', 'test' and 'cleanup'
    - { role: forecasting-server-001, tags: ['create-ami', 'test-ami'] }

    # These two following roles allow you to create and test an AMI of the automated system
    - { role: ec2-ami-001, tags: ['create-ami', 'test-ami'] }
    - { role: ec2-001, tags: ['test-ami'] }
  • Tags: configure, test, cleanup, create-ami, test-ami
---
- include: configure.yaml tags=configure

- include: test.yaml tags=test

- include: cleanup.yaml tags=cleanup

roles/forecasting-server-001/tasks/main.yaml

forecasting-server-001-playbook.yaml

test that your playbook is doing what you want it to do!

What you think your automation is doing...

What your automation is really doing...

$> Useful modules to test your playbook

- name: Make sure Nginx is started
  service:
    name: nginx
    state: started
- name: Wait for the service to be ready
  wait_for:
    host: "localhost"
    port: 8080
    delay: 5
    timeout: 320
- name: Make sure MySql is reachable from the outside
  wait_for:
    host: "{{ inventory_hostname }}"
    port: 3306
  delegate_to: tag_Name_webserver-1
- name: Make sure one API endpoint can be reached
  shell: "curl -XGET --head --silent \
    http://localhost:8080/hearbeat"
  register: res_request
  until: res_request.stdout.find("200 OK") != -1
  retries: 10
  delay: 10
- name: Collect info about java-7-oracle
  stat:
    path: '/opt/java-7-oracle'
  register: stat_jdk

- name: Make sure java-7-oracle exists
  assert:
    that:
      - "stat_jdk.stat.exists"
      - "stat_jdk.stat.isdir"

Orchestrate an application deployment

release-0

release-1

x5

x5

x5

x5

  • Take the instance(s) out of the load balancer
     
  • Deploy the new version 
     
  • Ensure the service is healthy
     
  • Put the instance back into the load balancer

x5

...

...

...

$> How ansible can help you

### ELB Deregister tasks

- name: Gathering ec2 facts
  ec2_facts:

- name: Taking the instance out of the ELB
  local_action: ec2_elb
  args:
    aws_access_key: "{{ aws_credentials_key_id }}"
    aws_secret_key: "{{ aws_credentials_secret_key }}"
    region: "{{ elb_region }}"
    instance_id: "{{ ansible_ec2_instance_id }}"
    state: 'absent'

### Release process

- name: Restarting the Fluentd td-agent process
  service: name=td-agent state=restarted

- name: Waiting for Fluentd input ports to be available
  wait_for: "port={{ item.value.source.port }} delay=0"
  with_dict: fluentd_forwarder_conf


### ELB register tasks

- name: Putting the instance back into the ELB
  local_action: ec2_elb
  args:
    aws_access_key: "{{ aws_credentials_key_id }}"
    aws_secret_key: "{{ aws_credentials_secret_key }}"
    region: "{{ elb_region }}"
    instance_id: "{{ ansible_ec2_instance_id }}"
    ec2_elbs: "{{ item }}"
    state: 'present'
    wait_timeout: 330
  with_items: ec2_elbs
---
- hosts: all
  serial: '5%'
  sudo: yes

  role:
    - fluentd-forwarder-release

QUESTION & ANSWER

Ansible Tips And Tricks

By Florian Dambrine

Ansible Tips And Tricks

Florian Dambrine (floriandambrine.com) from GumGum will share tips, tricks, best practices, observations, and feedback from using Ansible at GumGum. GumGum's operations team manages over 500 EC2 instances using over 60 Ansible roles that touch technologies like Cassandra, Elasticsearch, Storm, and Kafka among others. The talk will include a brief overview of Ansible along with plenty of great content from working with Ansible in the trenches, followed by Q and A, making this event ideal for both newbies and veterans. This is a special treat as Florian is in Los Angeles for just a brief time before returning to France. A BIG "thank you" goes to GumGum (gumgum.com) for sponsoring both the venue and food. Please RSVP on meetup.com for this event. general directions and parking: http://smpl.org/mainlibrary.aspx venue particulars: http://smpl.org/Services/Meeting_and_Study_Rooms/Multipurpose_Room.aspx Another special thank you to GumGum for hosting this event! GumGum is the leading in-image and in-screen advertising platform, driving brand engagement for advertisers and increased revenue for publishers across every screen. Our commitment to making brand advertising work better through technology and media drives higher viewability, relevance and brand engagement than standard display advertising.

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