DEV Community

Cover image for Packer in DevOps – Build Once, Deploy Anywhere
Pavithra Sai
Pavithra Sai

Posted on

Packer in DevOps – Build Once, Deploy Anywhere

Description:

Learn how HashiCorp Packer helps DevOps engineers automate machine image creation for cloud and CI/CD pipelines.
In DevOps, consistency and automation are very important.

Manual server setup often leads to errors and time waste.

This is where Packer helps us.
Tags: devops, packer, cloud, automation

Console Link: Official Packer Documentation

What is Packer?

Packer is an open-source tool developed by HashiCorp.

It is used to create machine images automatically.

Using Packer, we can build:

  • AWS AMIs
  • Azure VM Images
  • Google Cloud Images
  • Docker Images

Once an image is built, it can be reused anywhere.

Why Do We Need Packer?

Traditional approach:

  • Manual server configuration
  • Configuration mismatch
  • Slow deployments

With Packer:

  • Consistent images
  • Faster provisioning
  • Automation friendly
  • Works well with CI/CD

How Packer Works

  1. Write a Packer configuration file (.pkr.hcl)
  2. Choose a base OS image
  3. Use provisioners (Shell, Ansible, etc.)
  4. Run packer build
  5. Get a ready-to-use image

Real-Time Example

Imagine launching multiple EC2 instances with the same software.

Without Packer:

  • Manual setup for every server

With Packer:

  • Build AMI once
  • Launch multiple EC2 instances instantly

🙏 Acknowledgement

I would like to sincerely thank @santhoshnc for giving this assignment.

This task helped me explore Packer as a DevOps tool and understand how image automation plays a crucial role in real-world DevOps workflows.

The assignment motivated me to learn beyond theory and apply concepts practically.

Thank you, sir, for the guidance and encouragement.

Sample Packer Configuration


hcl
source "amazon-ebs" "example" {
  region        = "ap-south-1"
  instance_type = "t2.micro"
  ami_name      = "packer-demo-ami"
  source_ami    = "ami-xxxxxxxx"
  ssh_username  = "ubuntu"
}

build {
  sources = ["source.amazon-ebs.example"]

  provisioner "shell" {
    inline = [
      "sudo apt update",
      "sudo apt install nginx -y"
    ]
  }
}




Enter fullscreen mode Exit fullscreen mode

Top comments (0)