# Variables not loading from \*.auto.pkrvars.hcl files if no defaults in HCL

**URL:** <https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970>\
**Category:** Packer\
**Created:** [April 4, 2022, 3:45pm UTC](https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970 "2022-04-04T15:45:48Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![admin2](https://sea2.discourse-cdn.com/hashicorp/user_avatar/discuss.hashicorp.com/admin2/32/24346_2.png) [@admin2](https://discuss.hashicorp.com/u/admin2)\
**Post date:** [April 4, 2022, 3:45pm UTC](https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970/1 "2022-04-04T15:45:48Z")

</div>

When trying to follow the steps in the packer tutorial ([Variables | Packer - HashiCorp Learn](https://learn.hashicorp.com/tutorials/packer/docker-get-started-variables?in=packer/docker-get-started))

the variable definitions do not get auto loaded from the files within the directory unless a default value is included in the HCL file.

packer version: Packer v1.8.0  
OS: Linux 5.16.14-1-MANJARO

For the tutorial only 2 files are in use

docker-ubuntu.pkr.hcl  
variables.auto.pkrvars.hcl

docker-ubuntu.pkr.hcl

```auto
packer {
  required_plugins {
    docker = {
      version = ">= 0.0.7"
      source = "github.com/hashicorp/docker"
    }
  }
}

source "docker" "ubuntu" {
  image = var.docker_image
  commit = true
}

source "docker" "ubuntu-bionic" {
  image = "ubuntu:bionic"
  commit = true
}

build {
  name = "learn-packer"
  sources = [
    "source.docker.ubuntu",
    "source.docker.ubuntu-bionic"
  ]

  provisioner "shell" {
    environment_vars = [
      "FOO=hello world",
    ]
    inline = [
      "echo Adding file to Docker Container",
      "echo \"FOO is $FOO\" > example.txt",
    ]
  }
 
  post-processor "docker-tag" {
    repository = "learn-packer"
    tags = [var.docker_tag, "packer-rocks"]
    only = ["docker.ubuntu"]
  }

  post-processor "docker-tag" {
    repository = "learn-packer"
    tags = ["ubuntu-bionic", "packer-rocks"]
    only = ["docker.ubuntu-bionic"]
  }
}

```

variables.auto.pkrvars.hcl

```auto
docker_image = "ubuntu:groovy"
docker_tag = "ubuntu-groovy"

```

Then running

```auto
packer build .
Warning: Undefined variable

A "docker_image" variable was set but was not found in known variables. To
declare variable "docker_image", place this block in one of your .pkr files,
such as variables.pkr.hcl
....
--> learn-packer.docker.ubuntu-bionic: Imported Docker image: learn-packer:packer-rocks with tags learn-packer:ubuntu-bionic learn-packer:packer-rock

packer build -var-file=variables.auto.pkrvars.hcl .
Warning: Undefined variable

A "docker_image" variable was set but was not found in known variables. To
declare variable "docker_image", place this block in one of your .pkr files,
such as variables.pkr.hcl
....
--> learn-packer.docker.ubuntu-bionic: Imported Docker image: learn-packer:packer-rocks with tags learn-packer:ubuntu-bionic learn-packer:packer-rock

```

If I then add default variables to the hcl

docker-ubuntu.pkr.hcl

```auto
packer {
  required_plugins {
    docker = {
      version = ">= 0.0.7"
      source = "github.com/hashicorp/docker"
    }
  }
}

variable "docker_image" {
  type = string
  default = "ubuntu:xenial"
}

variable "docker_tag" {
  type = string
  default = "ubuntu-xenial"
}

source "docker" "ubuntu" {
  image = var.docker_image
  commit = true
}

source "docker" "ubuntu-bionic" {
  image = "ubuntu:bionic"
  commit = true
}

build {
  name = "learn-packer"
  sources = [
    "source.docker.ubuntu",
    "source.docker.ubuntu-bionic"
  ]

  provisioner "shell" {
    environment_vars = [
      "FOO=hello world",
    ]
    inline = [
      "echo Adding file to Docker Container",
      "echo \"FOO is $FOO\" > example.txt",
    ]
  }
 
  post-processor "docker-tag" {
    repository = "learn-packer"
    tags = [var.docker_tag, "packer-rocks"]
    only = ["docker.ubuntu"]
  }

  post-processor "docker-tag" {
    repository = "learn-packer"
    tags = ["ubuntu-bionic", "packer-rocks"]
    only = ["docker.ubuntu-bionic"]
  }
}

```

```auto
packer build .
....
--> learn-packer.docker.ubuntu: Imported Docker image: learn-packer:packer-rocks with tags learn-packer:ubuntu-groovy learn-packer:packer-rocks
--> learn-packer.docker.ubuntu-bionic: Imported Docker image: learn-packer:packer-rocks with tags learn-packer:ubuntu-bionic learn-packer:packer-rocks

```

It does not mention in the tutorial or in the documentation for variables that a default is required in order for build command to run and seems that the build and validate commands will only run correctly if defaults are included.

---

<div class="post-metadata">

**Author:** ![nikolai](https://sea2.discourse-cdn.com/hashicorp/user_avatar/discuss.hashicorp.com/nikolai/32/24238_2.png) [@nikolai](https://discuss.hashicorp.com/u/nikolai)\
**Post date:** [April 7, 2022, 7:19pm UTC](https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970/2 "2022-04-07T19:19:25Z")

</div>

+1 Thanks for pointing this out! Saved me a bunch of headache

---

<div class="post-metadata">

**Author:** ![SweetestSufferance](https://sea2.discourse-cdn.com/hashicorp/user_avatar/discuss.hashicorp.com/sweetestsufferance/32/27166_2.png) [@SweetestSufferance](https://discuss.hashicorp.com/u/SweetestSufferance)\
**Post date:** [April 12, 2022, 2:32pm UTC](https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970/3 "2022-04-12T14:32:47Z")

</div>

The documentation is a bit confusing, especially in regards the variable definitions and declarations.

What I’ve found is that the .pkrvar.hcl files are only for variable declaration, where the .pkr.hcl files are for the variable definitions, as well as the other subsections.

I was hoping that there was a way to define the variables outside of the main pkr.hcl files but, unfortunately, that doesn’t seem to be the case.

---

<div class="post-metadata">

**Author:** ![SweetestSufferance](https://sea2.discourse-cdn.com/hashicorp/user_avatar/discuss.hashicorp.com/sweetestsufferance/32/27166_2.png) [@SweetestSufferance](https://discuss.hashicorp.com/u/SweetestSufferance)\
**Post date:** [April 12, 2022, 11:18pm UTC](https://discuss.hashicorp.com/t/variables-not-loading-from-auto-pkrvars-hcl-files-if-no-defaults-in-hcl/37970/4 "2022-04-12T23:18:30Z")

</div>

It looks like you can have a variable definition file, variable declaration file, and a build template file. The only way I’ve got it to work is to call ./packer build .

Files:  
example\_def.auto.pkr.hcl

```auto
variable "image_id" {
    type = string
    default = "ami-1234"
}

```

example\_var.auto.pkrvars.hcl

```auto
image_id = "ami-5678"

```

example.pkr.hcl

```auto
source "null" "test"{
}

build {
  source "null.test" {
    ssh_host = "test"
    ssh_username = "test"
    communicator = "none"
  }

  provisioner "shell-local" {
    inline = [
      "echo ${var.image_id}"
    ]
  }
}

```

If all of the files above are in the same folder, and you call:  
`./packer build <folder>`

The output will be:

```auto
null.test: C:\packer>echo ami-5678
null.test: ami-5678

```

If the auto.pkrvars.hcl file is missing, then the variable will default to the default in the variable definition file.

Looking at a JSON convert to HCL file, using the hcl2\_upgrade parameter, I think I found what I was looking for.

```auto
# The HCL2 blocks in this file can be moved to other files. For example, the variable blocks could be

# moved to their own 'variables.pkr.hcl' file, etc. Those files need to be

# suffixed with '.pkr.hcl' to be visible to Packer. To use multiple files at

# once they also need to be in the same folder. 'packer inspect folder/'

# will describe to you what is in that folder.

```