---
layout: "docs"
page_title: "Amazon AMI Builder (instance-store)"
---

# AMI Builder (instance-store)

Type: `amazon-instance`

The `amazon-instance` builder is able to create Amazon AMIs backed by
instance storage as the root device. For more information on the difference
between instance storage and EBS-backed instances, see the
["storage for the root device" section in the EC2 documentation](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ComponentsAMIs.html#storage-for-the-root-device).

This builder builds an AMI by launching an EC2 instance from an existing
instance-storage backed AMI, provisioning that running machine, and then
bundling and creating a new AMI from that machine.
This is all done in your own AWS account. The builder will create temporary
keypairs, security group rules, etc. that provide it temporary access to
the instance while the image is being created. This simplifies configuration
quite a bit.

The builder does _not_ manage AMIs. Once it creates an AMI and stores it
in your account, it is up to you to use, delete, etc. the AMI.

## Configuration Reference

There are many configuration options available for the builder. They are
segmented below into two categories: required and optional parameters. Within
each category, the available configuration keys are alphabetized.

Required:

* `access_key` (string) - The access key used to communicate with AWS.
  If not specified, Packer will attempt to read this from environmental
  variables `AWS_ACCESS_KEY_ID` or `AWS_ACCESS_KEY` (in that order).

* `account_id` (string) - Your AWS account ID. This is required for bundling
  the AMI. This is _not the same_ as the access key. You can find your
  account ID in the security credentials page of your AWS account.

* `ami_name` (string) - The name of the resulting AMI that will appear
  when managing AMIs in the AWS console or via APIs. This must be unique.
  To help make this unique, use a function like `timestamp` (see
  [configuration templates](/docs/templates/configuration-templates.html) for more info)

* `instance_type` (string) - The EC2 instance type to use while building
  the AMI, such as "m1.small".

* `region` (string) - The name of the region, such as "us-east-1", in which
  to launch the EC2 instance to create the AMI.

* `s3_bucket` (string) - The name of the S3 bucket to upload the AMI.
  This bucket will be created if it doesn't exist.

* `secret_key` (string) - The secret key used to communicate with AWS.
  If not specified, Packer will attempt to read this from environmental
  variables `AWS_SECRET_ACCESS_KEY` or `AWS_SECRET_KEY` (in that order).

* `source_ami` (string) - The initial AMI used as a base for the newly
  created machine.

* `ssh_username` (string) - The username to use in order to communicate
  over SSH to the running machine.

* `x509_cert_path` (string) - The local path to a valid X509 certificate for
  your AWS account. This is used for bundling the AMI. This X509 certificate
  must be registered with your account from the security credentials page
  in the AWS console.

* `x509_key_path` (string) - The local path to the private key for the X509
  certificate specified by `x509_cert_path`. This is used for bundling the AMI.

Optional:

* `ami_block_device_mappings` (array of block device mappings) - Add the block
  device mappings to the AMI. The block device mappings allow for keys:
  "device\_name" (string), "virtual\_name" (string), "snapshot\_id" (string),
  "volume\_type" (string), "volume\_size" (int), "delete\_on\_termination"
  (bool), "no\_device" (bool), and "iops" (int).
  See [amazon-ebs](/docs/builders/amazon-ebs.html) for an example template.

* `ami_description` (string) - The description to set for the resulting
  AMI(s). By default this description is empty.

* `ami_groups` (array of string) - A list of groups that have access
  to launch the resulting AMI(s). By default no groups have permission
  to launch the AMI.

* `ami_product_codes` (array of string) - A list of product codes to
  associate with the AMI. By default no product codes are associated with
  the AMI.

* `ami_regions` (array of string) - A list of regions to copy the AMI to.
  Tags and attributes are copied along with the AMI. AMI copying takes time
  depending on the size of the AMI, but will generally take many minutes.

* `ami_users` (array of string) - A list of account IDs that have access
  to launch the resulting AMI(s). By default no additional users other than the user
  creating the AMI has permissions to launch it.

* `bundle_destination` (string) - The directory on the running instance
  where the bundled AMI will be saved prior to uploading. By default this is
  "/tmp". This directory must exist and be writable.

* `bundle_prefix` (string) - The prefix for files created from bundling
  the root volume. By default this is "image-{{timestamp}}". The `timestamp`
  variable should be used to make sure this is unique, otherwise it can
  collide with other created AMIs by Packer in your account.

* `bundle_upload_command` (string) - The command to use to upload the
  bundled volume. See the "custom bundle commands" section below for more
  information.

* `bundle_vol_command` (string) - The command to use to bundle the volume.
  See the "custom bundle commands" section below for more information.

* `iam_instance_profile` (string) - The name of an
  [IAM instance profile](http://docs.aws.amazon.com/IAM/latest/UserGuide/instance-profiles.html)
  to launch the EC2 instance with.

* `launch_block_device_mappings` (array of block device mappings) - Add the
  block device mappings to the launch instance. The block device mappings are
  the same as `ami_block_device_mappings` above.

* `security_group_id` (string) - The ID (_not_ the name) of the security
  group to assign to the instance. By default this is not set and Packer
  will automatically create a new temporary security group to allow SSH
  access. Note that if this is specified, you must be sure the security
  group allows access to the `ssh_port` given below.

* `security_group_ids` (array of string) - A list of security groups as
  described above. Note that if this is specified, you must omit the
  security_group_id.

* `ssh_port` (int) - The port that SSH will be available on. This defaults
  to port 22.

* `ssh_timeout` (string) - The time to wait for SSH to become available
  before timing out. The format of this value is a duration such as "5s"
  or "5m". The default SSH timeout is "1m", or one minute.

* `subnet_id` (string) - If using VPC, the ID of the subnet, such as
  "subnet-12345def", where Packer will launch the EC2 instance.

* `tags` (object of key/value strings) - Tags applied to the AMI.

* `user_data` (string) - User data to apply when launching the instance.
  Note that you need to be careful about escaping characters due to the
  templates being JSON. It is often more convenient to use `user_data_file`,
  instead.

* `user_data_file` (string) - Path to a file that will be used for the
  user data when launching the instance.

* `vpc_id` (string) - If launching into a VPC subnet, Packer needs the
  VPC ID in order to create a temporary security group within the VPC.

* `x509_upload_path` (string) - The path on the remote machine where the
  X509 certificate will be uploaded. This path must already exist and be
  writable. X509 certificates are uploaded after provisioning is run, so
  it is perfectly okay to create this directory as part of the provisioning
  process.

## Basic Example

Here is a basic example. It is completely valid except for the access keys:

<pre class="prettyprint">
{
  "type": "amazon-instance",
  "access_key": "YOUR KEY HERE",
  "secret_key": "YOUR SECRET KEY HERE",
  "region": "us-east-1",
  "source_ami": "ami-d9d6a6b0",
  "instance_type": "m1.small",
  "ssh_username": "ubuntu",

  "account_id": "0123-4567-0890",
  "s3_bucket": "packer-images",
  "x509_cert_path": "x509.cert",
  "x509_key_path": "x509.key",
  "x509_upload_path": "/tmp",

  "ami_name": "packer-quick-start {{timestamp}}"
}
</pre>

<div class="alert alert-block alert-info">
<strong>Note:</strong> Packer can also read the access key and secret
access key from environmental variables. See the configuration reference in
the section above for more information on what environmental variables Packer
will look for.
</div>

## Accessing the Instance to Debug

If you need to access the instance to debug for some reason, run the builder
with the `-debug` flag. In debug mode, the Amazon builder will save the
private key in the current directory and will output the DNS or IP information
as well. You can use this information to access the instance as it is
running.

## Custom Bundle Commands

A lot of the process required for creating an instance-store backed AMI
involves commands being run on the actual source instance. Specifically, the
`ec2-bundle-vol` and `ec2-upload-bundle` commands must be used to bundle
the root filesystem and upload it, respectively.

Each of these commands have a lot of available flags. Instead of exposing each
possible flag as a template configuration option, the instance-store AMI
builder for Packer lets you customize the entire command used to bundle
and upload the AMI.

These are configured with `bundle_vol_command` and `bundle_upload_command`.
Both of these configurations are
[configuration templates](/docs/templates/configuration-templates.html)
and have support for their own set of template variables.

### Bundle Volume Command

The default value for `bundle_vol_command` is shown below. It is split
across multiple lines for convenience of reading. The bundle volume command
is responsible for executing `ec2-bundle-vol` in order to store and image
of the root filesystem to use to create the AMI.

```
sudo -n ec2-bundle-vol \
	-k {{.KeyPath}}  \
	-u {{.AccountId}} \
	-c {{.CertPath}} \
	-r {{.Architecture}} \
	-e {{.PrivatePath}} \
	-d {{.Destination}} \
	-p {{.Prefix}} \
	--batch
```

The available template variables should be self-explanatory based on the
parameters they're used to satisfy the `ec2-bundle-vol` command.

<div class="alert alert-block">
  <strong>Warning!</strong> Some versions of ec2-bundle-vol silently
ignore all .pem and .gpg files during the bundling of the AMI, which can
cause problems on some systems, such as Ubuntu. You may want to
customize the bundle volume command to include those files (see the
<code>--no-filter</code> option of ec2-bundle-vol).
</div>

### Bundle Upload Command

The default value for `bundle_upload_command` is shown below. It is split
across multiple lines for convenience of reading. The bundle upload command
is responsible for taking the bundled volume and uploading it to S3.

```
sudo -n ec2-upload-bundle \
	-b {{.BucketName}} \
	-m {{.ManifestPath}} \
	-a {{.AccessKey}} \
	-s {{.SecretKey}} \
	-d {{.BundleDirectory}} \
	--batch \
	--retry
```

The available template variables should be self-explanatory based on the
parameters they're used to satisfy the `ec2-upload-bundle` command.
