HashiTalks 2025 Learn about unique use cases, homelab setups, and best practices at scale at our 24-hour virtual knowledge sharing event. Register
Packer
Packer Home

validate Command

The packer validate Packer command is used to validate the syntax and configuration of a template. The command will return a zero exit status on success, and a non-zero exit status on failure. Additionally, if a template doesn't validate, any error messages will be outputted.

Example usage:

$ packer validate my-template.pkr.hcl
Template validation failed. Errors are shown below.

Errors validating build 'vmware'. 1 error(s) occurred:

* Either a path or inline script must be specified.

Options

  • -syntax-only - Only the syntax of the template is checked. The configuration is not validated.

  • -evaluate-datasources - Evaluate all data sources when validating a template. This is only valid on HCL2 templates, since JSON templates do not feature datasources, this option will be ignored.

    Warning: Data sources may rely on external services for fetching data, which can incur some costs at validation if the services being contacted are billing per operation.

  • -except=foo,bar,baz - Validates all the builds except those with the comma-separated names. In legacy JSON templates, build names default to the types of their builders (e.g. docker or amazon-ebs or virtualbox-iso), unless a specific name attribute is specified within the configuration. In HCL2 templates, the "name" is the source block's "name" label, unless an in-build source definition adds the "name" configuration option.

  • -no-warn-undeclared-var - Silence warnings when the variable definition file contains variable assignments for undeclared variables. This can occur when using a var-file that contains a large amount of unused variables for a given HCL2 template. For HCL2 template defining a value for a variable in a var-file is not enough on its own for Packer to function, as there also needs to be a variable block definition in the template files pkr.hcl for the variable. By default packer validate will warn when a var-file contains one or more undeclared variables.

  • -only=foo,bar,baz - Only validate the builds with the given comma-separated names. In legacy JSON templates, build names default to the types of their builders (e.g. docker or amazon-ebs or virtualbox-iso), unless a specific name attribute is specified within the configuration. In HCL2 templates, the "name" is the source block's "name" label, unless an in-build source definition adds the "name" configuration option.

  • -machine-readable Sets all output to become machine-readable on stdout. Logging, if enabled, continues to appear on stderr.

  • -var - Set a variable in your Packer template. This option can be used multiple times. This is useful for setting version numbers for your build.

  • -var-file - Set template variables from a file.

Edit this page on GitHub