---
description: |
    The amazon-ebssurrogate Packer builder is like the chroot builder, but does
    not require running inside an EC2 instance.
layout: docs
page_title: 'Amazon EBS Surrogate - Builders'
sidebar_current: 'docs-builders-amazon-ebssurrogate'
---

# EBS Surrogate Builder

Type: `amazon-ebssurrogate`

The `amazon-ebssurrogate` Packer builder is able to create Amazon AMIs by
running a source instance with an attached volume, provisioning the attached
volume in such a way that it can be used as the root volume for the AMI, and
then snapshotting and creating the AMI from that volume.

This builder can therefore be used to bootstrap scratch-build images - for
example FreeBSD or Ubuntu using ZFS as the root file system.

This is all done in your own AWS account. The builder will create temporary key
pairs, security group rules, etc. that provide it temporary access to the
instance while the image is being created.

## 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.

In addition to the options listed here, a
[communicator](/docs/templates/communicator.html) can be configured for this
builder.

### Required:

-   `access_key` (string) - The access key used to communicate with AWS. [Learn
    how to set this.](/docs/builders/amazon.html#specifying-amazon-credentials)

-   `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.

-   `secret_key` (string) - The secret key used to communicate with AWS. [Learn
    how to set this.](/docs/builders/amazon.html#specifying-amazon-credentials)

-   `source_ami` (string) - The initial AMI used as a base for the newly
    created machine. `source_ami_filter` may be used instead to populate this
    automatically.

-   `ami_root_device` (block device mapping) - A block device mapping describing
    the root device of the AMI. This looks like the mappings in `ami_block_device_mapping`,
    except with an additional field:

    -   `source_device_name` (string) - The device name of the block device on the
        source instance to be used as the root device for the AMI. This must correspond
        to a block device in `launch_block_device_mapping`.

### Optional:

-   `ami_block_device_mappings` (array of block device mappings) - Add one or
    more [block device mappings](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html)
    to the AMI. These will be attached when booting a new instance from your
    AMI. To add a block device during the packer build see
    `launch_block_device_mappings` below. Your options here may vary depending
    on the type of VM you use. The block device mappings allow for the following
    configuration:

    -   `delete_on_termination` (boolean) - Indicates whether the EBS volume is
        deleted on instance termination. Default `false`. **NOTE**: If this
        value is not explicitly set to `true` and volumes are not cleaned up by
        an alternative method, additional volumes will accumulate after
        every build.

    -   `device_name` (string) - The device name exposed to the instance (for
        example, `/dev/sdh` or `xvdh`). Required when specifying `volume_size`.

    -   `encrypted` (boolean) - Indicates whether to encrypt the volume or not

    -   `iops` (number) - The number of I/O operations per second (IOPS) that the
        volume supports. See the documentation on
        [IOPs](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_EbsBlockDevice.html)
        for more information

    -   `no_device` (boolean) - Suppresses the specified device included in the
        block device mapping of the AMI

    -   `snapshot_id` (string) - The ID of the snapshot

    -   `virtual_name` (string) - The virtual device name. See the documentation on
        [Block Device
        Mapping](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_BlockDeviceMapping.html)
        for more information

    -   `volume_size` (number) - The size of the volume, in GiB. Required if not
        specifying a `snapshot_id`

    -   `volume_type` (string) - The volume type. `gp2` for General Purpose (SSD)
        volumes, `io1` for Provisioned IOPS (SSD) volumes, and `standard` for Magnetic
        volumes

-   `ami_description` (string) - The description to set for the
    resulting AMI(s). By default this description is empty. This is a
    [template engine](/docs/templates/engine.html),
    see [Build template data](#build-template-data) for more information.

-   `ami_groups` (array of strings) - A list of groups that have access to
    launch the resulting AMI(s). By default no groups have permission to launch
    the AMI. `all` will make the AMI publicly accessible. AWS currently doesn't
    accept any value other than `all`.

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

-   `ami_regions` (array of strings) - 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 strings) - 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.

-   `ami_virtualization_type` (string) - The type of virtualization for the AMI
    you are building. This option must match the supported virtualization
    type of `source_ami`. Can be `paravirtual` or `hvm`.

-   `associate_public_ip_address` (boolean) - If using a non-default VPC, public
    IP addresses are not provided by default. If this is toggled, your new
    instance will get a Public IP.

-   `availability_zone` (string) - Destination availability zone to launch
    instance in. Leave this empty to allow Amazon to auto-assign.

-   `block_duration_minutes` (int64) - Requires `spot_price` to
    be set. The required duration for the Spot Instances (also known as Spot blocks).
    This value must be a multiple of 60 (60, 120, 180, 240, 300, or 360).
    You can't specify an Availability Zone group or a launch group if you specify a duration.

-   `custom_endpoint_ec2` (string) - This option is useful if you use a cloud
    provider whose API is compatible with aws EC2. Specify another endpoint
    like this `https://ec2.custom.endpoint.com`.

-   `decode_authorization_messages` (boolean) - Enable automatic decoding of any
    encoded authorization (error) messages using the `sts:DecodeAuthorizationMessage` API.
    Note: requires that the effective user/role have permissions to `sts:DecodeAuthorizationMessage`
    on resource `*`. Default `false`.

-   `disable_stop_instance` (boolean) - Packer normally stops the build instance
    after all provisioners have run. For Windows instances, it is sometimes
    desirable to [run Sysprep](http://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/ami-create-standard.html)
    which will stop the instance for you. If this is set to true, Packer *will not*
    stop the instance but will assume that you will send the stop signal
    yourself through your final provisioner. You can do this with a
    [windows-shell provisioner](https://www.packer.io/docs/provisioners/windows-shell.html).

    Note that Packer will still wait for the instance to be stopped, and failing
    to send the stop signal yourself, when you have set this flag to `true`,
    will cause a timeout.

    Example of a valid shutdown command:

    ``` json
    {
      "type": "windows-shell",
      "inline": ["\"c:\\Program Files\\Amazon\\Ec2ConfigService\\ec2config.exe\" -sysprep"]
    }
    ```

-   `ebs_optimized` (boolean) - Mark instance as [EBS
    Optimized](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSOptimized.html).
    Default `false`.

-   `ena_support` (boolean) - Enable enhanced networking (ENA but not SriovNetSupport)
    on HVM-compatible AMIs. If true, add `ec2:ModifyInstanceAttribute` to your AWS IAM policy.
    Note: you must make sure enhanced networking is enabled on your instance. See [Amazon's
    documentation on enabling enhanced networking](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/enhanced-networking.html#enabling_enhanced_networking). Default `false`.

-   `enable_t2_unlimited` (boolean) - Enabling T2 Unlimited allows the source
    instance to burst additional CPU beyond its available [CPU Credits]
    (https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/t2-credits-baseline-concepts.html)
    for as long as the demand exists.
    This is in contrast to the standard configuration that only allows an
    instance to consume up to its available CPU Credits.
    See the AWS documentation for [T2 Unlimited]
    (https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/t2-unlimited.html)
    and the 'T2 Unlimited Pricing' section of the [Amazon EC2 On-Demand
    Pricing](https://aws.amazon.com/ec2/pricing/on-demand/) document for more
    information.
    By default this option is disabled and Packer will set up a [T2
    Standard](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/t2-std.html)
    instance instead.

    To use T2 Unlimited you must use a T2 instance type e.g. t2.micro.
    Additionally, T2 Unlimited cannot be used in conjunction with Spot
    Instances e.g. when the `spot_price` option has been configured.
    Attempting to do so will cause an error.

    !&gt; **Warning!** Additional costs may be incurred by enabling T2
    Unlimited - even for instances that would usually qualify for the
    [AWS Free Tier](https://aws.amazon.com/free/).

-   `force_deregister` (boolean) - Force Packer to first deregister an existing
    AMI if one with the same name already exists. Default `false`.

-   `force_delete_snapshot` (boolean) - Force Packer to delete snapshots associated with
    AMIs, which have been deregistered by `force_deregister`. Default `false`.

-   `encrypt_boot` (boolean) - Instruct packer to automatically create a copy of the
    AMI with an encrypted boot volume (discarding the initial unencrypted AMI in the
    process). Packer will always run this operation, even if the base
    AMI has an encrypted boot volume to start with. Default `false`.

-   `kms_key_id` (string) - The ID of the KMS key to use for boot volume encryption.
    This only applies to the main `region`, other regions where the AMI will be copied
    will be encrypted by the default EBS KMS key.

-   `iam_instance_profile` (string) - The name of an [IAM instance
    profile](https://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 one
    or more block devices before the Packer build starts. If you add instance
    store volumes or EBS volumes in addition to the root device volume, the
    created AMI will contain block device mapping information for those
    volumes. Amazon creates snapshots of the source instance's root volume and
    any other EBS volumes described here. When you launch an instance from this
    new AMI, the instance automatically launches with these additional volumes,
    and will restore them from snapshots taken from the source instance.

-   `mfa_code` (string) - The MFA [TOTP](https://en.wikipedia.org/wiki/Time-based_One-time_Password_Algorithm)
    code. This should probably be a user variable since it changes all the time.

-   `profile` (string) - The profile to use in the shared credentials file for
    AWS. See Amazon's documentation on [specifying
    profiles](https://docs.aws.amazon.com/sdk-for-go/v1/developer-guide/configuring-sdk.html#specifying-profiles)
    for more details.

-   `region_kms_key_ids` (map of strings) - a map of regions to copy the ami to,
    along with the custom kms key id to use for encryption for that region.
    Keys must match the regions provided in `ami_regions`. If you just want to
    encrypt using a default ID, you can stick with `kms_key_id` and `ami_regions`.
    If you want a region to be encrypted with that region's default key ID, you can
    use an empty string `""` instead of a key id in this map. (e.g. `"us-east-1": ""`)
    However, you cannot use default key IDs if you are using this in conjunction with
    `snapshot_users` -- in that situation you must use custom keys.

-   `run_tags` (object of key/value strings) - Tags to apply to the instance
    that is *launched* to create the AMI. These tags are *not* applied to the
    resulting AMI unless they're duplicated in `tags`. This is a
    [template engine](/docs/templates/engine.html),
    see [Build template data](#build-template-data) for more information.

-   `run_volume_tags` (object of key/value strings) - Tags to apply to the volumes
    that are *launched* to create the AMI. These tags are *not* applied to the
    resulting AMI unless they're duplicated in `tags`. This is a
    [template engine](/docs/templates/engine.html),
    see [Build template data](#build-template-data) for more information.

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

-   `temporary_security_group_source_cidr` (string) - An IPv4 CIDR block to be authorized
    access to the instance, when packer is creating a temporary security group.
    The default is `0.0.0.0/0` (ie, allow any IPv4 source). This is only used
    when `security_group_id` or `security_group_ids` is not specified.

-   `shutdown_behavior` (string) - Automatically terminate instances on shutdown
    incase packer exits ungracefully. Possible values are "stop" and "terminate",
    default is `stop`.

-   `skip_region_validation` (boolean) - Set to true if you want to skip
    validation of the region configuration option. Default `false`.

-   `snapshot_groups` (array of strings) - A list of groups that have access to
    create volumes from the snapshot(s). By default no groups have permission to create
    volumes from the snapshot(s). `all` will make the snapshot publicly accessible.

-   `snapshot_users` (array of strings) - A list of account IDs that have access to
    create volumes from the snapshot(s). By default no additional users other than the
    user creating the AMI has permissions to create volumes from the backing snapshot(s).

-   `snapshot_tags` (object of key/value strings) - Tags to apply to snapshot.
    They will override AMI tags if already applied to snapshot. This is a
    [template engine](/docs/templates/engine.html),
    see [Build template data](#build-template-data) for more information.

-   `source_ami_filter` (object) - Filters used to populate the `source_ami` field.
    Example:

    ``` json
    {
      "source_ami_filter": {
        "filters": {
          "virtualization-type": "hvm",
          "name": "ubuntu/images/*ubuntu-xenial-16.04-amd64-server-*",
          "root-device-type": "ebs"
        },
        "owners": ["099720109477"],
        "most_recent": true
      }
    }
    ```

    This selects the most recent Ubuntu 16.04 HVM EBS AMI from Canonical.
    NOTE: This will fail unless *exactly* one AMI is returned. In the above
    example, `most_recent` will cause this to succeed by selecting the newest image.

    -   `filters` (map of strings) - filters used to select a `source_ami`.
        NOTE: This will fail unless *exactly* one AMI is returned.
        Any filter described in the docs for [DescribeImages](http://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeImages.html)
        is valid.

    -   `owners` (array of strings) - Filters the images by their owner. You may
        specify one or more AWS account IDs, "self" (which will use the account
        whose credentials you are using to run Packer), or an AWS owner alias:
        for example, "amazon", "aws-marketplace", or "microsoft".
        This option is required for security reasons.


    -   `most_recent` (boolean) - Selects the newest created image when true.
        This is most useful for selecting a daily distro build.

    You may set this in place of `source_ami` or in conjunction with it. If you
    set this in conjunction with `source_ami`, the `source_ami` will be added to
    the filter. The provided `source_ami` must meet all of the filtering criteria
    provided in `source_ami_filter`; this pins the AMI returned by the filter,
    but will cause Packer to fail if the `source_ami` does not exist.

-   `spot_price` (string) - The maximum hourly price to pay for a spot instance
    to create the AMI. Spot instances are a type of instance that EC2 starts
    when the current spot price is less than the maximum price you specify. Spot
    price will be updated based on available spot instance capacity and current
    spot instance requests. It may save you some costs. You can set this to
    `auto` for Packer to automatically discover the best spot price or to "0"
    to use an on demand instance (default).

-   `spot_price_auto_product` (string) - Required if `spot_price` is set
    to `auto`. This tells Packer what sort of AMI you're launching to find the
    best spot price. This must be one of: `Linux/UNIX`, `SUSE Linux`, `Windows`,
    `Linux/UNIX (Amazon VPC)`, `SUSE Linux (Amazon VPC)`, `Windows (Amazon VPC)`

-   `spot_tags` (object of key/value strings) - Requires `spot_price` to
    be set. This tells Packer to apply tags to the spot request that is
    issued.

-   `sriov_support` (boolean) - Enable enhanced networking (SriovNetSupport but not ENA)
    on HVM-compatible AMIs. If true, add `ec2:ModifyInstanceAttribute` to your AWS IAM
    policy. Note: you must make sure enhanced networking is enabled on your instance. See [Amazon's
    documentation on enabling enhanced networking](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/enhanced-networking.html#enabling_enhanced_networking).
    Default `false`.

-   `ssh_keypair_name` (string) - If specified, this is the key that will be
    used for SSH with the machine. The key must match a key pair name loaded
    up into Amazon EC2. By default, this is blank, and Packer will
    generate a temporary keypair unless
    [`ssh_password`](/docs/templates/communicator.html#ssh_password) is used.
    [`ssh_private_key_file`](/docs/templates/communicator.html#ssh_private_key_file)
    or `ssh_agent_auth` must be specified when `ssh_keypair_name` is utilized.

-   `ssh_agent_auth` (boolean) - If true, the local SSH agent will be used to
    authenticate connections to the source instance. No temporary keypair will
    be created, and the values of `ssh_password` and `ssh_private_key_file` will
    be ignored. To use this option with a key pair already configured in the source
    AMI, leave the `ssh_keypair_name` blank. To associate an existing key pair
    in AWS with the source instance, set the `ssh_keypair_name` field to the name
    of the key pair.

-   `ssh_private_ip` (boolean) - No longer supported. See
    [`ssh_interface`](#ssh_interface). A fixer exists to migrate.

-   `ssh_interface` (string) - One of `public_ip`, `private_ip`,
    `public_dns` or `private_dns`. If set, either the public IP address,
    private IP address, public DNS name or private DNS name will used as the host for SSH.
    The default behaviour if inside a VPC is to use the public IP address if available,
    otherwise the private IP address will be used. If not in a VPC the public DNS name
    will be used. Also works for WinRM.

    Where Packer is configured for an outbound proxy but WinRM traffic should be direct,
    `ssh_interface` must be set to `private_dns` and `<region>.compute.internal` included
    in the `NO_PROXY` environment variable.

-   `subnet_id` (string) - If using VPC, the ID of the subnet, such as
    `subnet-12345def`, where Packer will launch the EC2 instance. This field is
    required if you are using an non-default VPC.

-   `tags` (object of key/value strings) - Tags applied to the AMI and
    relevant snapshots. This is a
    [template engine](/docs/templates/engine.html),
    see [Build template data](#build-template-data) for more information.

-   `temporary_key_pair_name` (string) - The name of the temporary keypair
    to generate. By default, Packer generates a name with a UUID.

-   `token` (string) - The access token to use. This is different from the
    access key and secret key. If you're not sure what this is, then you
    probably don't need it. This will also be read from the `AWS_SESSION_TOKEN`
    environmental variable.

-   `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. Requires `subnet_id`
    to be set. If this field is left blank, Packer will try to get the VPC ID from the
    `subnet_id`.

-   `windows_password_timeout` (string) - The timeout for waiting for a Windows
    password for Windows instances. Defaults to 20 minutes. Example value: `10m`

## Basic Example

``` json
{
   "type" : "amazon-ebssurrogate",
   "secret_key" : "YOUR SECRET KEY HERE",
   "access_key" : "YOUR KEY HERE",
   "region" : "us-east-1",
   "ssh_username" : "ubuntu",
   "instance_type" : "t2.medium",
   "source_ami" : "ami-40d28157",
   "launch_block_device_mappings" : [
     {
       "volume_type" : "gp2",
       "device_name" : "/dev/xvdf",
       "delete_on_termination" : false,
       "volume_size" : 10
     }
   ],
   "ami_root_device": {
     "source_device_name": "/dev/xvdf",
     "device_name": "/dev/xvda",
     "delete_on_termination": true,
     "volume_size": 16,
     "volume_type": "gp2"
   }
}
```

-&gt; **Note:** 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.

Further information on locating AMI IDs and their relationship to instance
types and regions can be found in the AWS EC2 Documentation
[for Linux](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/finding-an-ami.html)
or [for Windows](http://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/finding-an-ami.html).

## 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.

## Build template data

The available variables are:

- `BuildRegion` - The region (for example `eu-central-1`) where Packer is building the AMI.
- `SourceAMI` - The source AMI ID (for example `ami-a2412fcd`) used to build the AMI.
- `SourceAMIName` - The source AMI Name (for example `ubuntu/images/ebs-ssd/ubuntu-xenial-16.04-amd64-server-20180306`) used to build the AMI.
- `SourceAMITags` - The source AMI Tags, as a `map[string]string` object.


-&gt; **Note:** Packer uses pre-built AMIs as the source for building images.
These source AMIs may include volumes that are not flagged to be destroyed on
termination of the instance building the new image. In addition to those volumes
created by this builder, any volumes inn the source AMI which are not marked for
deletion on termination will remain in your account.
