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content/blog/snapshotswithpacker.md

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+---
+title: "Snapshot Creation with Packer"
+date: 2020-05-08T22:31:40-04:00
+draft: false
+tags: []
+---
+
+[Packer](https://www.packer.io/) is a tool to create automated machine images in both local virtual machine / container environments, as well as a variety of cloud platforms. My current cloud platform of choice is [Digital Ocean](https://www.digitalocean.com/), so this post will explain how to set up Packer with it. Though you can likely find your platform of choice on their [docs](https://www.packer.io/docs/builders/) page
+
+In this post I am going to use the beta configuration language of HCL2. This requires a Packer version of at least 1.5.
+
+## Variables
+
+First let us set up a variables file which we will later reference. This makes it easy to keep your main Packer configuration files in Git, while not committing your API key.
+
+Create a file called `variables.auto.pkrvars.hcl`. Here is some example variables and values that I put in mine.
+
+```
+base_system_image = "ubuntu-20-04-x64"
+region = "nyc3"
+size = "512mb"
+do_token = "DOTOKENHERE" # Secret
+```
+
+Then we need to create `variables.pkr.hcl` that define the types of each of these variables
+
+```
+variable "do_token" {
+  type = string
+}
+
+variable "base_system_image" {
+  type = string
+}
+
+variable "region" {
+  type = string
+}
+
+variable "size" {
+  type = string
+}
+```
+
+## Provisioning
+
+Once the system is up and running we can use a [variety of tools](https://www.packer.io/docs/provisioners/) that setup the image.
+
+- Ansible
+- Chef
+- Powershell
+- etc.
+
+I'll use a simple bash script as an example
+
+```bash
+#!/bin/bash
+apt update
+apt upgrade -y
+```
+
+## Piecing it together
+
+Finally let us create a `do.pkr.hcl` file that contains the following information
+
+```
+source "digitalocean" "web" {
+  api_token = var.do_token
+  image = var.base_system_image
+  region = var.region
+  size = var.size
+  ssh_username = "root"
+  snapshot_name = "packer-example"
+}
+
+
+build {
+  sources = [
+    "source.digitalocean.web",
+  ]
+
+  provisioner "shell" {
+    scripts = [ "setup.sh" ]
+  }
+}
+```
+
+Assuming all the files we've just created are in the same directory, Packer will automatically recognize where the value for `var.do_token` lives. We can then run packer to build the image
+
+```bash
+packer build .
+```
+
+This sets up a snapshot called `packer-example` which we can later spin up and use! Keep in mind that it does a small amount of money to store images on DigitalOcean. 
+