What is Packer? Features and Examples
What is Packer? Packer is an open-source tool from HashiCorp that automates the creation of machine images. Think of it as a “factory” that takes a base image (Ubuntu, CentOS, Windows) and produces consistent, pre-configured VM or cloud images ready for deployment. Instead of manually preparing servers or VMs, you define everything in a template, and Packer does the work. Key Features Multi-platform builds — Create images for AWS AMI, Azure, Google Cloud, VMware, VirtualBox, Docker, and more, all at once. Immutable infrastructure — Instead of configuring servers after they start, you ship pre-baked images. Automation-friendly — Works well with CI/CD pipelines. Extensible — Supports plugins for provisioners (e.g., Ansible, Chef, Puppet, shell scripts). Example: Simple Packer Template { "builders": [{ "type": "docker", "image": "ubuntu:20.04", "commit": true }], "provisioners": [{ "type": "shell", "inline": ["apt-get update", "apt-get install -y nginx"] }] } What happens here: Start with ubuntu:20.04 Docker image. Run provisioning (install Nginx). Save the result as a new Docker image. When to Use Packer Building goldeggn images for production (with pre-installed dependencies). Standardizing environments across multiple clouds. Speeding up autoscaling by using pre-baked images. Conclusion Packer helps developers and DevOps engineers avoid “snowflake servers” and instead work with predictable, automated images. If your infrastructure spans multiple platforms, Packer is a great way to keep things consistent. ...