Best way to launch aws ec2 instances with ansible

As others have said, the cloud module contains just about all the AWS provisioning support you'd need. That said, Ansible's paradigm makes most sense once there's an existing SSH:able machine to target and connect to. The instantiation phase, by comparison, essentially asks you to target your local machine and calls AWS API endpoints from there.

Like you, I wanted a single-shot command with a graceful transition from EC2 instantiation into its configuration. There's suggestions on how to accomplish something like this in the documentation, but it relies on the the add_host module to tweak Ansible's idea of current host inventory, and even then I couldn't find a solution that didn't feel like i was working against rather than with the system.

In the end I opted for two distinct playbooks: a provision.yml that uses the ec2, ec2_group, ec2_vol, ec2_eip and route53 modules to ensure I have the "hardware" in place, and then configure.yml, more like a traditional Ansible site.yml, which is able to treat host inventory (static in my case, but dynamic will work well) as a given and do all that good declarative state transitioning.

Both playbooks are idempotent, but it's configure.yml that's meant to be rerun over and over in the long run.


This is the short answer of your question, if you want detail and fully automated role, please let me know. Thanks

Prerequisite:

  • Ansible

  • Python boto library

  • Set up the AWS access and secret keys in the environment settings
    (best is inside the ~./boto)

To Create the EC2 Instance(s):

In order to create the EC2 Instance, please modified these parameters that you can find inside the "ec2_launch.yml" file under "vars":

  • region # where is want to launch the instance(s), USA, Australia, Ireland etc
  • count # Number of instance(s), you want to create

    Once, you have mentioned these parameter, please run the following command:

ansible-playbook -i hosts ec2_launch.yml

Contents of hosts file:

[local]
localhost

[webserver]

Contents of ec2_launch.yml file:

---
  - name: Provision an EC2 Instance
    hosts: local
    connection: local
    gather_facts: False
    tags: provisioning
    # Necessary Variables for creating/provisioning the EC2 Instance
    vars:
      instance_type: t1.micro
      security_group: webserver # Change the security group name here
      image: ami-98aa1cf0 # Change the AMI, from which you want to launch the server
      region: us-east-1 # Change the Region
      keypair: ansible # Change the keypair name
      count: 1

    # Task that will be used to Launch/Create an EC2 Instance
    tasks:

      - name: Create a security group
        local_action: 
          module: ec2_group
          name: "{{ security_group }}"
          description: Security Group for webserver Servers
          region: "{{ region }}"
          rules:
            - proto: tcp
              type: ssh
              from_port: 22
              to_port: 22
              cidr_ip: 0.0.0.0/0
            - proto: tcp
              from_port: 80
              to_port: 80
              cidr_ip: 0.0.0.0/0
          rules_egress:
            - proto: all
              type: all
              cidr_ip: 0.0.0.0/0


      - name: Launch the new EC2 Instance
        local_action: ec2 
                      group={{ security_group }} 
                      instance_type={{ instance_type}} 
                      image={{ image }} 
                      wait=true 
                      region={{ region }} 
                      keypair={{ keypair }}
                      count={{count}}
        register: ec2

      - name: Add the newly created EC2 instance(s) to the local host group (located inside the directory)
        local_action: lineinfile 
                      dest="./hosts" 
                      regexp={{ item.public_ip }} 
                      insertafter="[webserver]" line={{ item.public_ip }}
        with_items: "{{ ec2.instances }}"


      - name: Wait for SSH to come up
        local_action: wait_for 
                      host={{ item.public_ip }} 
                      port=22 
                      state=started
        with_items: "{{ ec2.instances }}"

      - name: Add tag to Instance(s)
        local_action: ec2_tag resource={{ item.id }} region={{ region }} state=present
        with_items: "{{ ec2.instances }}"
        args:
          tags:
            Name: webserver