How using ansible you can manage and deploy instances on cloud stack

1. September2016
Using Ansible to manage instances on CloudPlatform
By
Kiran Manohar Chavala
@kiranchavala
kiranchavala@gmail.com

2. © 2016 Accelerite. All Rights Reserved.2
Agenda
• Configuration Management
• Why Ansible is required
• Installing Ansible
• Hands on session on a practicle example of Ansible
• Deploying Cloudstack Management server

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Why Configuration management is important
• I need these services to be installed and running
• I need this configuration file to contain these lines
• I need this file to exist in this directory
• Centralization of configuration
• Creation of reusable template configurations i.e. web servers, database servers, DHCP servers,
Cloudstack management servers

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What is Configuration Management?
• Configuration management is the philosophy of defining the state that a server
should be in wrt it’s configuration and using tools that achieve that state
• CM gives centralization of configuration data and actions
• Configuration Management tools should be idempotent

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What is Idempotent
Operations in mathematics and computer science, that can be applied multiple times without changing the result
beyond the initial application.
• You need to add the following lines to the default my.cnf:
innodb_rollback_on_timeout=1
innodb_lock_wait_timeout=600
max_connections=350
• A sed command would add the lines
sed -i -e '/symbolic-links=0/ ainnodb_rollback_on_timeout=1' -e '/symbolic-links=0/ ainnodb_lock_wait_timeout=600' -e
'/symbolic-links=0/ amax_connections=350' /etc/my.cnf
• But if you needed to run your script to update/restore another setting then the addition of these lines would be repeated
• A configuration management tool would not add these lines aga

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How Ansible is different then Chef and Puppet
Technical:
• Client/Server architecture not required
• Only SSH connectivity required (password or public/private keys) making it easier to deploy in
environments
• Modules can be in any language capable of returning JSON or key=value text pairs
• Has an API
User:
Don’t need to learn a programming language (i.e. Ruby)
Chef and puppet are pull-based by default. Agent installed on the servers periodically check in with a central
service and pull down con

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Basic Terminologies
• Host Inventories
• Roles
• Tasks
• Variables (hosts or groups)
• Modules
• Templates
• Playbooks

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Installing Ansible
• Install a centos 6 .x machine
• yum install wget
• wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
• wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm
• sudo rpm -Uvh remi-release-6*.rpm epel-release-6*.rpm
• yum install -y ansible

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Configuring Ansible
• yum install openssh-server openssh-clients
• Yum install git
ssh-keygen -t rsa
ssh-copy-id root@remote machine you want to control
[root@anscont3 playbooks1]# cat hosts
ansibleremote ansible_ssh_host=10.104.49.233 ansible_ssh_port=22
[root@anscont3 playbooks1]# cat ansible.cfg
[defaults]
hostfile = hosts
remote_user = root
private_key_file=/root/.ssh/id_rsa
host_key_checking = False

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Use Case Scenarios
• The remote machine should have set of predefined packages installed
https://github.com/fifthecho/CloudStack-Template
git clone https://github.com/fifthecho/CloudStack-Template.git

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Deploying Cloudstack components using Anisble
• http://docs.cloudstack.apache.org/en/latest/ansible.html
• http://docs.ansible.com/ansible/guide_cloudstack.html
• https://github.com/resmo/ansible-cloudstack

12. Thank You!