6.1 KiB
description: |
The googlecompute Packer builder is able to create images for use with Google
Compute Engine (GCE) based on existing images. Google Compute Engine doesn't
allow the creation of images from scratch.
layout: docs
page_title: Google Compute Builder
...
Google Compute Builder
Type: googlecompute
The googlecompute Packer builder is able to create
images for use with Google
Compute Engine(GCE) based on
existing images. Google Compute Engine doesn't allow the creation of images from
scratch.
Authentication
Authenticating with Google Cloud services requires at most one JSON file, called
the account file. The account file is not required if you are running
the googlecompute Packer builder from a GCE instance with a
properly-configured Compute Engine Service
Account.
Running With a Compute Engine Service Account
If you run the googlecompute Packer builder from a GCE instance, you can
configure that instance to use a Compute Engine Service
Account. This will allow
Packer to authenticate to Google Cloud without having to bake in a separate
credential/authentication file.
To create a GCE instance that uses a service account, provide the required scopes when launching the instance.
For gcloud, do this via the --scopes parameter:
gcloud compute --project YOUR_PROJECT instances create "INSTANCE-NAME" ... \
--scopes "https://www.googleapis.com/auth/compute" \
"https://www.googleapis.com/auth/devstorage.full_control" \
...
For the Google Developers Console:
- Choose "Show advanced options"
- Tick "Enable Compute Engine service account"
- Choose "Read Write" for Compute
- Chose "Full" for "Storage"
The service account will be used automatically by Packer as long as there is no account file specified in the Packer configuration file.
Running Without a Compute Engine Service Account
The Google Developers Console allows
you to create and download a credential file that will let you use the
googlecompute Packer builder anywhere. To make the process more
straightforwarded, it is documented here.
-
Log into the Google Developers Console and select a project.
-
Under the "APIs & Auth" section, click "Credentials."
-
Click the "Create new Client ID" button, select "Service account", and click "Create Client ID"
-
Click "Generate new JSON key" for the Service Account you just created. A JSON file will be downloaded automatically. This is your account file.
Basic Example
Below is a fully functioning example. It doesn't do anything useful, since no provisioners are defined, but it will effectively repackage an existing GCE image. The account_file is obtained in the previous section. If it parses as JSON it is assumed to be the file itself, otherwise it is assumed to be the path to the file containing the JSON.
{
"type": "googlecompute",
"account_file": "account.json",
"project_id": "my-project",
"source_image": "debian-7-wheezy-v20150127",
"zone": "us-central1-a"
}
Configuration Reference
Configuration options are organized below into two categories: required and optional. Within each category, the available options are alphabetized and described.
In addition to the options listed here, a communicator can be configured for this builder.
Required:
-
project_id(string) - The project ID that will be used to launch instances and store images. -
source_image(string) - The source image to use to create the new image from. Example:"debian-7-wheezy-v20150127" -
zone(string) - The zone in which to launch the instance used to create the image. Example:"us-central1-a"
Optional:
-
account_file(string) - The JSON file containing your account credentials. Not required if you run Packer on a GCE instance with a service account. Instructions for creating file or using service accounts are above. -
address(string) - The name of a pre-allocated static external IP address. Note, must be the name and not the actual IP address. -
disk_size(integer) - The size of the disk in GB. This defaults to10, which is 10GB. -
image_name(string) - The unique name of the resulting image. Defaults to"packer-{{timestamp}}". -
image_description(string) - The description of the resulting image. -
instance_name(string) - A name to give the launched instance. Beware that this must be unique. Defaults to"packer-{{uuid}}". -
machine_type(string) - The machine type. Defaults to"n1-standard-1". -
metadata(object of key/value strings) -
network(string) - The Google Compute network to use for the launched instance. Defaults to"default". -
preemptible(boolean) - If true, launch a preembtible instance. -
region(string) - The region in which to launch the instance. Defaults to to the region hosting the specifiedzone. -
state_timeout(string) - The time to wait for instance state changes. Defaults to"5m". -
subnetwork(string) - The Google Compute subnetwork to use for the launced instance. Only required if thenetworkhas been created with custom subnetting. Note, the region of the subnetwork must match theregionorzonein which the VM is launched. -
tags(array of strings) -
use_internal_ip(boolean) - If true, use the instance's internal IP instead of its external IP during building.
Gotchas
Centos images have root ssh access disabled by default. Set ssh_username to
any user, which will be created by packer with sudo access.
The machine type must have a scratch disk, which means you can't use an
f1-micro or g1-small to build images.