3.2 KiB

Raw Blame History

layout	page_title	sidebar_current	description
docs	Provisioners	docs-provisioners	Provisioners are used to execute scripts on a local or remote machine as part of resource creation or destruction.

Provisioners

Provisioners are used to execute scripts on a local or remote machine as part of resource creation or destruction. Provisioners can be used to bootstrap a resource, cleanup before destroy, run configuration management, etc.

Provisioners are added directly to any resource:

resource "aws_instance" "web" {
    # ...

    provisioner "local-exec" {
        command = "echo ${self.private_ip_address} > file.txt"
    }
}

For provisioners other than local execution, you must specify connection settings so Terraform knows how to communicate with the resource.

Creation-Time Provisioners

Provisioners by default run when the resource they are defined within is created. Creation-time provisioners are only run during creation, not during updating or any other lifecycle. They are meant as a means to perform bootstrapping of a system.

If a creation-time provisioner fails, the resource is marked as tainted. A tainted resource will be planned for destruction and recreation upon the next terraform apply. Terraform does this because a failed provisioner can leave a resource in a semi-configured state. Because Terraform cannot reason about what the provisioner does, the only way to ensure proper creation of a resource is to recreate it. This is tainting.

You can change this behavior by setting the on_failure attribute, which is covered in detail below.

Destroy-Time Provisioners

If when = "destroy" is specified, the provisioner will run when the resource it is defined within is destroyed.

Destroy provisioners are run before the resource is destroyed. If they fail, Terraform will error and rerun the provisioners again on the next terraform apply. Due to this behavior, care should be taken for destroy provisioners to be safe to run multiple times.

Multiple Provisioners

Multiple provisioners can be specified within a resource. Multiple provisioners are executed in the order they're defined in the configuration file.

You may also mix and match creation and destruction provisioners. Only the provisioners that are valid for a given operation will be run. Those valid provisioners will be run in the order they're defined in the configuration file.

Example of multiple provisioners:

resource "aws_instance" "web" {
    # ...

    provisioner "local-exec" {
        command = "echo first"
    }

    provisioner "local-exec" {
        command = "echo second"
    }
}

Failure Behavior

By default, provisioners that fail will also cause the Terraform apply itself to error. The on_failure setting can be used to change this. The allowed values are:

"continue" - Ignore the error and continue with creation or destruction.
"fail" - Error (the default behavior). If this is a creation provisioner, taint the resource.

Example:

resource "aws_instance" "web" {
    # ...

    provisioner "local-exec" {
        command = "echo ${self.private_ip_address} > file.txt"
        on_failure = "continue"
    }
}

3.2 KiB Raw Blame History