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Formatting a Packer Template in HCL2
Packer allows us to create templates for generating cross-platform machine images, and HashiCorp provides its own configuration language for this task. In this lab, we'll test our HCL2 skills by fixing and otherwise neaten up an inaccurately written HCL2 Packer template. Just want to test your HCL2 reviewing skills? No Packer knowledge is needed to take this lab.

Lab Info
Table of Contents
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Challenge
Fix Whitespace
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Open the provided template:
cd packer
vim ami-test.pkr.hcl
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To make viewing the template easier, let's neaten up the template by adjusting the tabs/whitespace:
source "amazon-ebs" "ubuntu-ami-test": { access_key = "", secret_key = "", security_group_ids = [""], subnet_id = "", region = "us-east-1", ami_name = "ubuntu-ami-test_{{timestamp}}", instance_type = "t2.micro", source_ami = "ami-068663a3c619dd892", communicator = "ssh", ssh_username = "ubuntu" } build { sources = [ "source.amazon-ebs.ubuntu-ami-test" ] provisioner "shell" [ script = "init.sh" ] }
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Challenge
Adjust Structural Errors
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Update the template to remove the unnecessary colon (
:
) in the initialsource
block. Theprovisioner
block also needs to be updated to work as an object not an array:source "amazon-ebs" "ubuntu-ami-test" { access_key = "", secret_key = "", security_group_ids = [""], subnet_id = "", region = "us-east-1", ami_name = "ubuntu-ami-test_{{timestamp}}", instance_type = "t2.micro", source_ami = "ami-068663a3c619dd892", communicator = "ssh", ssh_username = "ubuntu" } build { sources = [ "source.amazon-ebs.ubuntu-ami-test" ] provisioner "shell" { script = "init.sh" } }
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Finally, remove any commas:
source "amazon-ebs" "ubuntu-ami-test" { access_key = "" secret_key = "" security_group_ids = [""] subnet_id = "" region = "us-east-1" ami_name = "ubuntu-ami-test_{{timestamp}}" instance_type = "t2.micro" source_ami = "ami-068663a3c619dd892" communicator = "ssh" ssh_username = "ubuntu" } build { sources = [ "source.amazon-ebs.ubuntu-ami-test" ] provisioner "shell" { script = "init.sh" } }
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Challenge
Run the Build
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Using the credentials on the hands-on lab page, update the variables to use the provided access key, secret key, subnet ID, and security group.
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Save and exit the file.
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Run the build:
packer build .
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About the author
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