• Website: https://www.packer.io
• IRC: #packer-tool on Freenode
• Mailing list: Google Groups

Packer is a tool for building identical machine images for multiple platforms from a single source configuration.

Packer is lightweight, runs on every major operating system, and is highly performant, creating machine images for multiple platforms in parallel. Packer comes out of the box with support for the following platforms:

• Amazon EC2 (AMI). Both EBS-backed and instance-store AMIs
• DigitalOcean
• Docker
• Google Compute Engine
• OpenStack
• Parallels
• QEMU. Both KVM and Xen images.
• VirtualBox
• VMware

Support for other platforms can be added via plugins.

The images that Packer creates can easily be turned into Vagrant boxes.

Note: There is a great introduction and getting started guide for those with a bit more patience. Otherwise, the quick start below will get you up and running quickly, at the sacrifice of not explaining some key points.

First, download a pre-built Packer binary for your operating system or compile Packer yourself.

After Packer is installed, create your first template, which tells Packer what platforms to build images for and how you want to build them. In our case, we'll create a simple AMI that has Redis pre-installed. Save this file as quick-start.json. Be sure to replace any credentials with your own.

{
  "builders": [{
    "type": "amazon-ebs",
    "access_key": "YOUR KEY HERE",
    "secret_key": "YOUR SECRET KEY HERE",
    "region": "us-east-1",
    "source_ami": "ami-de0d9eb7",
    "instance_type": "t1.micro",
    "ssh_username": "ubuntu",
    "ami_name": "packer-example {{timestamp}}"
  }]
}

Next, tell Packer to build the image:

$ packer build quick-start.json
...

Packer will build an AMI according to the "quick-start" template. The AMI will be available in your AWS account. To delete the AMI, you must manually delete it using the AWS console. Packer builds your images, it does not manage their lifecycle. Where they go, how they're run, etc. is up to you.

Full, comprehensive documentation is viewable on the Packer website:

https://www.packer.io/docs

If you wish to work on Packer itself or any of its built-in providers, you'll first need Go installed (version 1.2+ is required). Make sure Go is properly installed, including setting up a GOPATH.

Next, install the following software packages, which are needed for some dependencies:

• Bazaar
• Git
• Mercurial

Then, install Gox, which is used as a compilation tool on top of Go:

$ go get -u github.com/mitchellh/gox

Next, clone this repository into $GOPATH/src/github.com/mitchellh/packer. Install the necessary dependencies by running make updatedeps and then just type make. This will compile some more dependencies and then run the tests. If this exits with exit status 0, then everything is working!

$ make updatedeps
...
$ make
...

To compile a development version of Packer and the built-in plugins, run make dev. This will put Packer binaries in the bin folder:

$ make dev
...
$ bin/packer
...

If you're developing a specific package, you can run tests for just that package by specifying the TEST variable. For example below, only packer package tests will be run.

$ make test TEST=./packer
...