ORFMI - Open Rainforest Machine Image

A Python CLI tool for creating AWS AMIs from configuration files and setup scripts.

Installation

pip install orfmi

Usage

Using a Configuration File

orfmi --config-file config.yml --setup-file setup.sh

Using CLI Flags

orfmi --ami-name my-ami \
      --region us-east-1 \
      --source-ami "debian-12-*" \
      --subnet-ids subnet-12345,subnet-67890 \
      --instance-types t3.micro,t3.small \
      --security-group-id sg-12345abc \
      --setup-file setup.sh

Arguments

Required (one of)

Either use --config-file OR provide all individual flags:

• --config-file FILE - Path to the YAML configuration file
• --ami-name NAME - Name for the created AMI
• --region REGION - AWS region
• --source-ami AMI_ID - Source AMI name pattern
• --subnet-ids SUBNETS - Comma-separated subnet IDs
• --instance-types TYPES - Comma-separated instance types
• --security-group-id SG_ID - Security group ID

Always Required

• --setup-file FILE - Path to the setup script (bash or PowerShell)

Optional

• --ami-description DESC - Description for the AMI
• --iam-instance-profile PROFILE - IAM instance profile name
• --purchase-type TYPE - Purchase type: on-demand or spot
• --max-retries N - Maximum retries on capacity errors (default: 3)
• --ssh-username USER - SSH username for connecting (default: admin)
• --ssh-timeout SECONDS - SSH timeout in seconds (default: 300)
• --ssh-retries N - SSH connection retries (default: 30)
• --platform PLATFORM - Platform: linux or windows (default: linux)
• --tags TAGS - Tags as key=value,key=value (e.g., Name=test,Env=prod)
• -v, --verbose - Enable verbose output
• -q, --quiet - Suppress output except for errors and the final AMI ID

Configuration File

The configuration file is a YAML file with the following structure:

# Required fields
ami_name: my-custom-ami
region: us-east-1
source_ami: debian-12-*  # AMI name pattern to search for
subnet_ids:
  - subnet-12345abc
  - subnet-67890def
instance_types:
  - t3.micro
  - t3.small
security_group_id: sg-12345abc

# Optional fields
ami_description: My custom AMI for production
iam_instance_profile: my-instance-profile
purchase_type: on-demand  # on-demand or spot, default: on-demand
max_retries: 3            # default: 3 retries on capacity errors
ssh_username: admin       # default: admin
ssh_timeout: 300          # default: 300 seconds
ssh_retries: 30           # default: 30 retries
platform: linux           # linux or windows, default: linux
tags:
  Name: my-ami
  Environment: production

Required Fields

Optional Fields

Setup Script

The setup script runs on the instance to configure it before creating the AMI.

Linux (Bash)

#!/bin/bash
set -e

# Update packages
apt-get update
apt-get upgrade -y

# Install required software
apt-get install -y docker.io git

# Enable services
systemctl enable docker

# Clean up
apt-get clean
rm -rf /var/lib/apt/lists/*

Windows (PowerShell)

# Install Chocolatey
Set-ExecutionPolicy Bypass -Scope Process -Force
$url = 'https://chocolatey.org/install.ps1'
iex ((New-Object System.Net.WebClient).DownloadString($url))

# Install software
choco install -y git docker-desktop

Exit Codes

Output

On success, the tool outputs the AMI ID in the format:

AMI_ID=ami-0123456789abcdef0

How It Works

1. Parses the configuration file or CLI arguments
2. Looks up the source AMI by name pattern
3. Creates temporary resources (key pair, launch template)
4. Launches an EC2 instance using EC2 Fleet (on-demand or spot)
5. Waits for the instance to be ready
6. Connects via SSH and runs the setup script
7. Creates an AMI from the configured instance
8. Cleans up temporary resources
9. Outputs the AMI ID

Retry Logic

The tool automatically retries on capacity errors (e.g., insufficient capacity, instance limit exceeded) and spot instance interruptions. Use --max-retries to configure the maximum number of retry attempts.