EC2 Instance Connect Connection Plugin for Ansible

The EC2 Instance Connect (ECI) connection plugin was created to take advantage of AWS's ECI capability Rather than rely on public keys statically stored on resources, this allows us to take advantage of using AWS native roles and permissions to access and manage linux servers instead.

This is helpful in situations where you need to use continue to use ansible over AWS native instance management solutions, but want to take advantage of AWS's native IAM model for authorization as well as to avoid sharing of long living private keys.

Check releases for versions of this library for older Ansible versions

Installation into Ansible

Drop eci.py into a connection plugin location, as outlined in https://docs.ansible.com/ansible/latest/dev_guide/developing_locally.html. Must have boto3 and ec2instanceconnectcli python libraries available

AWS Servers must be set up to support EC2 Instance Connect.

Parameters

For parameter details, use ansible-doc -t connection eci

In general, aligned to the same requirements as most other aws related modules and tasks in ansible. Namely, in one way or another AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY must be set, and we must also have region. Generally, this is set either at the host level or globally.

TODO: The connection plugin can take either instance_id or use ip address (public or private) or hostname to determine the correct connection details.

Local Testing

We test the plugin by doing the following:

1. Create a security group (opening port 22 from 0.0.0.0/0)
2. Creates a t2.micro aws linux ami; doesn't set any keypair, so not accessible with 'normal' ssh
3. Connects using eci with instance-id & ip address (preferred) information as root, echo basic message
4. Connects using eci with ip address host information as ec2-user, echo basic message

Env Setup

Using WSL2 or a Linux instance, setup a new python venv

python3 -m venv venv/
source venv/bin/activate
pip install requirements.txt
ansible-galaxy collection install amazon.aws

Make sure the plugin is being pulled in correctly... from the workspace directory, run the following command to make sure you're getting the connection info: env ANSIBLE_CONNECTION_PLUGINS=./plugins/connection ansible-doc -t connection eci

Running playbook

Continuing in your venv, set the AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY for the account the test should run in, then run the test

export AWS_ACCESS_KEY_ID='<<YOUR_ACCESS_KEY_ID>>'
export AWS_SECRET_ACCESS_KEY='<<YOUR_SECRET_ACCESS_KEY>>'
cd /workspaces/ansible-eci-connector/test
env ANSIBLE_CONNECTION_PLUGINS=../plugins/connection ansible-playbook -vv demo.yml

Why not MSSH?

While mssh may be an option as well, it was important to ensure better support for everything the original SSH provider has

TODO

• IP Address to instance id (or vice versa?) lookup
• remove temp keys when run finishes
• Look at incorporating into or deprecating in favor of ansible-collections/community.aws
• • The S3 bucket does add additional complexity that this avoids...