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The Amazon plugin can be used with HashiCorp Packer to create custom images on AWS.
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Updated 2 years ago
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Amazon EBS
Type: amazon-ebs
Artifact BuilderId: mitchellh.amazonebs
The amazon-ebs
Packer builder is able to create Amazon AMIs backed by EBS
volumes for use in EC2. For more information on
the difference between EBS-backed instances and instance-store backed
instances, see the "storage for the root device" section in the EC2
documentation.
This builder builds an AMI by launching an EC2 instance from a source AMI, provisioning that running machine, and then creating an 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.
Note: Temporary resources are, by default, all created with the
prefix packer
. This can be useful if you want to restrict the security groups
and key pairs Packer is able to operate on.
EBS Specific Configuration Reference
There are many configuration options available for the builder. In addition to the items listed here, you will want to look at the general configuration references for AMI, BlockDevices, Access, Run and Communicator configuration references, which are necessary for this build to succeed and can be found further down the page.
Optional:
skip_create_ami
(bool) - If true, Packer will not create the AMI. Useful for setting totrue
during a build test stage. Defaultfalse
.ami_block_device_mappings
(awscommon.BlockDevices) - Add one or more block device mappings to the AMI. These will be attached when booting a new instance from your AMI. To add a block device during the Packer build seelaunch_block_device_mappings
below. Your options here may vary depending on the type of VM you use. See the BlockDevices documentation for fields.launch_block_device_mappings
(awscommon.BlockDevices) - 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. See the BlockDevices documentation for fields.run_volume_tags
(map[string]string) - 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 intags
. This is a template engine, see Build template data for more information.run_volume_tag
([]{name string, value string}) - Same asrun_volume_tags
but defined as a singular block containing aname
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.no_ephemeral
(bool) - Relevant only to Windows guests: If you set this flag, we'll add clauses to the launch_block_device_mappings that make sure ephemeral drives don't show up in the EC2 console. If you launched from the EC2 console, you'd get this automatically, but the SDK does not provide this service. For more information, see https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/InstanceStorage.html. Because we don't validate the OS type of your guest, it is up to you to make sure you don't set this for *nix guests; behavior may be unpredictable.fast_launch
(FastLaunchConfig) - The configuration for fast launch support.Fast launch is only relevant for Windows AMIs, and should not be used for other OSes. See the Fast Launch Configuration section for information on the attributes supported for this block.
AMI Configuration
Required:
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 template engine for more info).
Optional:
ami_description
(string) - The description to set for the resulting AMI(s). By default this description is empty. This is a template engine, see Build template data for more information.ami_virtualization_type
(string) - The type of virtualization for the AMI you are building. This option is required to register HVM images. Can be paravirtual (default) or hvm.ami_users
([]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.ami_groups
([]string) - 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_org_arns
([]string) - A list of Amazon Resource Names (ARN) of AWS Organizations that have access to launch the resulting AMI(s). By default no organizations have permission to launch the AMI.ami_ou_arns
([]string) - A list of Amazon Resource Names (ARN) of AWS Organizations organizational units (OU) that have access to launch the resulting AMI(s). By default no organizational units have permission to launch the AMI.ami_product_codes
([]string) - A list of product codes to associate with the AMI. By default no product codes are associated with the AMI.ami_regions
([]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.skip_region_validation
(bool) - Set to true if you want to skip validation of the ami_regions configuration option. Default false.tags
(map[string]string) - Key/value pair tags applied to the AMI. This is a template engine, see Build template data for more information.The builder no longer adds a "Name": "Packer Builder" entry to the tags.
tag
([]{key string, value string}) - Same astags
but defined as a singular repeatable block containing akey
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.ena_support
(boolean) - Enable enhanced networking (ENA but not SriovNetSupport) on HVM-compatible AMIs. If set, addec2: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.
sriov_support
(bool) - Enable enhanced networking (SriovNetSupport but not ENA) on HVM-compatible AMIs. If true, addec2: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. Defaultfalse
.force_deregister
(bool) - Force Packer to first deregister an existing AMI if one with the same name already exists. Default false.force_delete_snapshot
(bool) - Force Packer to delete snapshots associated with AMIs, which have been deregistered by force_deregister. Default false.encrypt_boot
(boolean) - Whether or not to encrypt the resulting AMI when copying a provisioned instance to an AMI. By default, Packer will keep the encryption setting to what it was in the source image. Setting false will result in an unencrypted image, and true will result in an encrypted one.If you have used the
launch_block_device_mappings
to set an encryption key and that key is the same as the one you want the image encrypted with at the end, then you don't need to set this field; leaving it empty will prevent an unnecessary extra copy step and save you some time.Please note that if you are using an account with the global "Always encrypt new EBS volumes" option set to
true
, Packer will be unable to override this setting, and the final image will be encrypted whether you set this value or not.kms_key_id
(string) - ID, alias or ARN of the KMS key to use for AMI encryption. This only applies to the mainregion
-- any regions the AMI gets copied to will be encrypted by the default EBS KMS key for that region, unless you set region-specific keys inregion_kms_key_ids
.Set this value if you select
encrypt_boot
, but don't want to use the region's default KMS key.If you have a custom kms key you'd like to apply to the launch volume, and are only building in one region, it is more efficient to leave this and
encrypt_boot
empty and to instead set the key id in the launch_block_device_mappings (you can find an example below). This saves potentially many minutes at the end of the build by preventing Packer from having to copy and re-encrypt the image at the end of the build.For valid formats see KmsKeyId in the AWS API docs - CopyImage. This field is validated by Packer, when using an alias, you will have to prefix
kms_key_id
withalias/
.region_kms_key_ids
(map[string]string) - regions to copy the ami to, along with the custom kms key id (alias or arn) to use for encryption for that region. Keys must match the regions provided inami_regions
. If you just want to encrypt using a default ID, you can stick withkms_key_id
andami_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 withsnapshot_users
-- in that situation you must use custom keys. For valid formats see KmsKeyId in the AWS API docs - CopyImage.This option supercedes the
kms_key_id
option -- if you set both, and they are different, Packer will respect the value inregion_kms_key_ids
for your build region and silently disregard the value provided inkms_key_id
.skip_save_build_region
(bool) - If true, Packer will not check whether an AMI with theami_name
exists in the region it is building in. It will use an intermediary AMI name, which it will not convert to an AMI in the build region. It will copy the intermediary AMI into any regions provided inami_regions
, then delete the intermediary AMI. Defaultfalse
.imds_support
(string) - Enforce version of the Instance Metadata Service on the built AMI. Valid options are unset (legacy) andv2.0
. See the documentation on IMDS for more information. Defaults to legacy.deprecate_at
(string) - The date and time to deprecate the AMI, in UTC, in the following format: YYYY-MM-DDTHH:MM:SSZ. If you specify a value for seconds, Amazon EC2 rounds the seconds to the nearest minute. You can’t specify a date in the past. The upper limit for DeprecateAt is 10 years from now.deregistration_protection
(DeregistrationProtectionOptions) - Enable AMI deregistration protection. See DeregistrationProtectionOptions below for more details on all of the options available, and for a usage example.
snapshot_tags
(map[string]string) - Key/value pair tags to apply to snapshot. They will override AMI tags if already applied to snapshot. This is a template engine, see Build template data for more information.snapshot_tag
([]{key string, value string}) - Same assnapshot_tags
but defined as a singular repeatable block containing akey
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.snapshot_users
([]string) - 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_groups
([]string) - 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.
Access Configuration
Required:
access_key
(string) - The access key used to communicate with AWS. Learn how to set this. On EBS, this is not required if you are usinguse_vault_aws_engine
for authentication instead.region
(string) - The name of the region, such asus-east-1
, in which to launch the EC2 instance to create the AMI. When chroot building, this value is guessed from environment.secret_key
(string) - The secret key used to communicate with AWS. Learn how to set this. This is not required if you are usinguse_vault_aws_engine
for authentication instead.
Optional:
assume_role
(AssumeRoleConfig) - If provided with a role ARN, Packer will attempt to assume this role using the supplied credentials. See AssumeRoleConfig below for more details on all of the options available, and for a usage example.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.shared_credentials_file
(string) - Path to a credentials file to load credentials fromdecode_authorization_messages
(bool) - Enable automatic decoding of any encoded authorization (error) messages using thests:DecodeAuthorizationMessage
API. Note: requires that the effective user/role have permissions tosts:DecodeAuthorizationMessage
on resource*
. Defaultfalse
.insecure_skip_tls_verify
(bool) - This allows skipping TLS verification of the AWS EC2 endpoint. The default is false.max_retries
(int) - This is the maximum number of times an API call is retried, in the case where requests are being throttled or experiencing transient failures. The delay between the subsequent API calls increases exponentially.mfa_code
(string) - The MFA TOTP 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 for more details.skip_metadata_api_check
(bool) - Skip Metadata Api Checkskip_credential_validation
(bool) - Set to true if you want to skip validating AWS credentials before runtime.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.vault_aws_engine
(VaultAWSEngineOptions) - Get credentials from HashiCorp Vault's aws secrets engine. You must already have created a role to use. For more information about generating credentials via the Vault engine, see the Vault docs. If you set this flag, you must also set the below options:name
(string) - Required. Specifies the name of the role to generate credentials against. This is part of the request URL.engine_name
(string) - The name of the aws secrets engine. In the Vault docs, this is normally referred to as "aws", and Packer will default to "aws" ifengine_name
is not set.role_arn
(string)- The ARN of the role to assume if credential_type on the Vault role is assumed_role. Must match one of the allowed role ARNs in the Vault role. Optional if the Vault role only allows a single AWS role ARN; required otherwise.ttl
(string) - Specifies the TTL for the use of the STS token. This is specified as a string with a duration suffix. Valid only when credential_type is assumed_role or federation_token. When not specified, the default_sts_ttl set for the role will be used. If that is also not set, then the default value of 3600s will be used. AWS places limits on the maximum TTL allowed. See the AWS documentation on the DurationSeconds parameter for AssumeRole (for assumed_role credential types) and GetFederationToken (for federation_token credential types) for more details.
HCL2 example:
JSON example:
aws_polling
(*AWSPollingConfig) - Polling configuration for the AWS waiter. Configures the waiter that checks resource state.
Assume Role Configuration
AssumeRoleConfig lets users set configuration options for assuming a special role when executing Packer.
Usage example:
HCL config example:
JSON config example:
role_arn
(string) - Amazon Resource Name (ARN) of the IAM Role to assume.duration_seconds
(int) - Number of seconds to restrict the assume role session duration.external_id
(string) - The external ID to use when assuming the role. If omitted, no external ID is passed to the AssumeRole call.policy
(string) - IAM Policy JSON describing further restricting permissions for the IAM Role being assumed.policy_arns
([]string) - Set of Amazon Resource Names (ARNs) of IAM Policies describing further restricting permissions for the IAM Role beingsession_name
(string) - Session name to use when assuming the role.tags
(map[string]string) - Map of assume role session tags.transitive_tag_keys
([]string) - Set of assume role session tag keys to pass to any subsequent sessions.
Polling Configuration
Polling configuration for the AWS waiter. Configures the waiter for resources creation or actions like attaching volumes or importing image.
HCL2 example:
JSON example:
max_attempts
(int) - Specifies the maximum number of attempts the waiter will check for resource state. This value can also be set via the AWS_MAX_ATTEMPTS. If both option and environment variable are set, the max_attempts will be considered over the AWS_MAX_ATTEMPTS. If none is set, defaults to AWS waiter default which is 40 max_attempts.delay_seconds
(int) - Specifies the delay in seconds between attempts to check the resource state. This value can also be set via the AWS_POLL_DELAY_SECONDS. If both option and environment variable are set, the delay_seconds will be considered over the AWS_POLL_DELAY_SECONDS. If none is set, defaults to AWS waiter default which is 15 seconds.
Run Configuration
Required:
instance_type
(string) - The EC2 instance type to use while building the AMI, such as t2.small.source_ami
(string) - The source AMI whose root volume will be copied and provisioned on the currently running instance. This must be an EBS-backed AMI with a root volume snapshot that you have access to.
Optional:
associate_public_ip_address
(boolean) - If using a non-default VPC, public IP addresses are not provided by default. If this is true, your new instance will get a Public IP. default: unsetNote: when specifying this attribute without a
subnet_[id|filter]
orvpc_[id|filter]
, we will attempt to infer this information from the default VPC/Subnet. This operation may require some extra permissions to the IAM role that runs the build:- ec2:DescribeVpcs
- ec2:DescribeSubnets
Additionally, since we filter subnets/AZs by their capability to host an instance of the selected type, you may also want to define the
ec2:DescribeInstanceTypeOfferings
action to the role running the build. Otherwise, Packer will pick the most available subnet in the VPC selected, which may not be able to host the instance type you provided.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. Note: This parameter is no longer available to new customers from July 1, 2021. See Amazon's documentation.capacity_reservation_preference
(string) - Set the preference for using a capacity reservation if one exists. Either will beopen
ornone
. Defaults tonone
capacity_reservation_id
(string) - Provide the specific EC2 Capacity Reservation ID that will be used by Packer.capacity_reservation_group_arn
(string) - Provide the EC2 Capacity Reservation Group ARN that will be used by Packer.disable_stop_instance
(bool) - Packer normally stops the build instance after all provisioners have run. For Windows instances, it is sometimes desirable to run Sysprep which will stop the instance for you. If this is set totrue
, 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. 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 totrue
, will cause a timeout.An example of a valid windows shutdown command in a
windows-shell
provisioner is :or
Note: The double quotation marks in the command are not required if your CMD shell is already in the
C:\Program Files\Amazon\EC2ConfigService\
directory.ebs_optimized
(bool) - Mark instance as EBS Optimized. Defaultfalse
.enable_nitro_enclave
(bool) - Enable support for Nitro Enclaves on the instance. Note that the instance type must be able to support Nitro Enclaves. This option is not supported for spot instances.enable_t2_unlimited
(bool) - Deprecated argument - please use "enable_unlimited_credits". Enabling T2 Unlimited allows the source instance to burst additional CPU beyond its available CPU Credits 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 and the T2 Unlimited Pricing section of the Amazon EC2 On-Demand Pricing document for more information. By default this option is disabled and Packer will set up a T2 Standard 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 thespot_price
option has been configured. Attempting to do so will cause an error.!> Warning! Additional costs may be incurred by enabling T2 Unlimited - even for instances that would usually qualify for the AWS Free Tier.
enable_unlimited_credits
(bool) - Enabling Unlimited credits allows the source instance to burst additional CPU beyond its available CPU Credits 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 and the Unlimited Pricing section of the Amazon EC2 On-Demand Pricing document for more information. By default this option is disabled and Packer will set up a Standard instance instead.To use Unlimited you must use a T2/T3/T3a/T4g instance type, e.g. (
t2.micro
,t3.micro
). Additionally, Unlimited cannot be used in conjunction with Spot Instances for T2 type instances, e.g. when thespot_price
option has been configured. Attempting to do so will cause an error if the underlying instance type is a T2 type instance. By default the supported burstable instance types (including t3/t3a/t4g) will be provisioned with its cpu credits set to standard, only whenenable_unlimited_credits
is true will the instance be provisioned with unlimited cpu credits.iam_instance_profile
(string) - The name of an IAM instance profile to launch the EC2 instance with.fleet_tags
(map[string]string) - Key/value pair tags to apply tags to the fleet that is issued.fleet_tag
([]{key string, value string}) - Same asfleet_tags
but defined as a singular repeatable block containing akey
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.skip_profile_validation
(bool) - Whether or not to check if the IAM instance profile exists. Defaults to falsetemporary_iam_instance_profile_policy_document
(*PolicyDocument) - Temporary IAM instance profile policy document If IamInstanceProfile is specified it will be used instead.HCL2 example:
JSON example:
shutdown_behavior
(string) - Automatically terminate instances on shutdown in case Packer exits ungracefully. Possible values are stop and terminate. Defaults to stop.security_group_filter
(SecurityGroupFilterOptions) - Filters used to populate thesecurity_group_ids
field.HCL2 Example:
JSON Example:
This selects the SG's with tag
Class
with the valuepacker
.filters
(map[string,string] | multiple filters are allowed when seperated by commas) - filters used to select asecurity_group_ids
. Any filter described in the docs for DescribeSecurityGroups is valid.
security_group_ids
take precedence over this.run_tags
(map[string]string) - Key/value pair tags to apply to the generated key-pair, security group, iam profile and role, snapshot, network interfaces and instance that is launched to create the EBS volumes. The resulting AMI will also inherit these tags. This is a template engine, see Build template data for more information.run_tag
([]{key string, value string}) - Same asrun_tags
but defined as a singular repeatable block containing akey
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.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
([]string) - A list of security groups as described above. Note that if this is specified, you must omit the security_group_id.source_ami_filter
(AmiFilterOptions) - Filters used to populate thesource_ami
field.HCL2 example:
JSON Example:
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[string,string] | multiple filters are allowed when seperated by commas) - filters used to select asource_ami
. NOTE: This will fail unless exactly one AMI is returned. Any filter described in the docs for DescribeImages 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
, ormicrosoft
. 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 withsource_ami
, thesource_ami
will be added to the filter. The providedsource_ami
must meet all of the filtering criteria provided insource_ami_filter
; this pins the AMI returned by the filter, but will cause Packer to fail if thesource_ami
does not exist.
spot_instance_types
([]string) - a list of acceptable instance types to run your build on. We will request a spot instance using the max price of spot_price and the allocation strategy of "lowest price". Your instance will be launched on an instance type of the lowest available price that you have in your list. This is used in place of instance_type. You may only set either spot_instance_types or instance_type, not both. This feature exists to help prevent situations where a Packer build fails because a particular availability zone does not have capacity for the specific instance_type requested in instance_type.spot_price
(string) - With Spot Instances, you pay the Spot price that's in effect for the time period your instances are running. Spot Instance prices are set by Amazon EC2 and adjust gradually based on long-term trends in supply and demand for Spot Instance capacity.When this field is set, it represents the maximum hourly price you are willing to pay for a spot instance. If you do not set this value, it defaults to a maximum price equal to the on demand price of the instance. In the situation where the current Amazon-set spot price exceeds the value set in this field, Packer will not launch an instance and the build will error. In the situation where the Amazon-set spot price is less than the value set in this field, Packer will launch and you will pay the Amazon-set spot price, not this maximum value. For more information, see the Amazon docs on spot pricing.
spot_tags
(map[string]string) - Requires spot_price to be set. Key/value pair tags to apply tags to the spot request that is issued.spot_tag
([]{key string, value string}) - Same asspot_tags
but defined as a singular repeatable block containing akey
and avalue
field. In HCL2 mode thedynamic_block
will allow you to create those programatically.subnet_filter
(SubnetFilterOptions) - Filters used to populate thesubnet_id
field.HCL2 example:
JSON Example:
This selects the Subnet with tag
Class
with the valuebuild
, which has the most free IP addresses. NOTE: This will fail unless exactly one Subnet is returned. By usingmost_free
orrandom
one will be selected from those matching the filter.filters
(map[string,string] | multiple filters are allowed when seperated by commas) - filters used to select asubnet_id
. NOTE: This will fail unless exactly one Subnet is returned. Any filter described in the docs for DescribeSubnets is valid.most_free
(boolean) - The Subnet with the most free IPv4 addresses will be used if multiple Subnets matches the filter.random
(boolean) - A random Subnet will be used if multiple Subnets matches the filter.most_free
have precendence over this.subnet_id
take precedence over this.
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.license_specifications
([]LicenseSpecification) - The license configurations.HCL2 example:
JSON example:
Each
license_configuration_request
describes a license configuration, the properties of which are:license_configuration_arn
(string) - The Amazon Resource Name (ARN) of the license configuration.
placement
(Placement) - Describes the placement of an instance.HCL2 example:
JSON example:
Refer to the Placement docs for more information on the supported attributes for placement configuration.
tenancy
(string) - Deprecated: Use Placement Tenancy instead.temporary_security_group_source_cidrs
([]string) - A list of IPv4 CIDR blocks to be authorized access to the instance, when packer is creating a temporary security group.The default is [
0.0.0.0/0
] (i.e., allow any IPv4 source). Usetemporary_security_group_source_public_ip
to allow current host's public IP instead of any IPv4 source. This is only used whensecurity_group_id
orsecurity_group_ids
is not specified.temporary_security_group_source_public_ip
(bool) - When enabled, use public IP of the host (obtained from https://checkip.amazonaws.com) as CIDR block to be authorized access to the instance, when packer is creating a temporary security group. Defaults tofalse
.This is only used when
security_group_id
,security_group_ids
, andtemporary_security_group_source_cidrs
are not specified.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. Packer will not automatically wait for a user script to finish before shutting down the instance this must be handled in a provisioner.user_data_file
(string) - Path to a file that will be used for the user data when launching the instance.vpc_filter
(VpcFilterOptions) - Filters used to populate thevpc_id
field.HCL2 example:
JSON Example:
This selects the VPC with tag
Class
with the valuebuild
, which is not the default VPC, and have a IPv4 CIDR block of/24
. NOTE: This will fail unless exactly one VPC is returned.filters
(map[string,string] | multiple filters are allowed when seperated by commas) - filters used to select avpc_id
. NOTE: This will fail unless exactly one VPC is returned. Any filter described in the docs for DescribeVpcs is valid.
vpc_id
take precedence over this.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
(duration string | ex: "1h5m2s") - The timeout for waiting for a Windows password for Windows instances. Defaults to 20 minutes. Example value: 10mmetadata_options
(MetadataOptions) - Metadata Settingsssh_interface
(string) - One ofpublic_ip
,private_ip
,public_dns
,private_dns
orsession_manager
. If set, either the public IP address, private IP address, public DNS name or private DNS name will be 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 toprivate_dns
and<region>.compute.internal
included in theNO_PROXY
environment variable.When using
session_manager
the machine running Packer must have the AWS Session Manager Plugin installed and within the users' system path. Connectivity via thesession_manager
interface establishes a secure tunnel between the local host and the remote host on an available local port to the specifiedssh_port
. See Session Manager Connections for more information.- Session manager connectivity is currently only implemented for the SSH communicator, not the WinRM communicator.
- Upon termination the secure tunnel will be terminated automatically, if however there is a failure in terminating the tunnel it will automatically terminate itself after 20 minutes of inactivity.
pause_before_ssm
(duration string | ex: "1h5m2s") - The time to wait before establishing the Session Manager session. The value of this should be a duration. Examples are5s
and1m30s
which will cause Packer to wait five seconds and one minute 30 seconds, respectively. If no set, defaults to 10 seconds. This option is useful when the remote port takes longer to become available.session_manager_port
(int) - Which port to connect the local end of the session tunnel to. If left blank, Packer will choose a port for you from available ports. This option is only used whenssh_interface
is setsession_manager
.
Placement Configuration
host_resource_group_arn
(string) - The ARN of the host resource group in which to launch the instances.host_id
(string) - The ID of the host used when Packer launches an EC2 instance.tenancy
(string) - Tenancy used when Packer launches the EC2 instance, allowing it to be launched on dedicated hardware.The default is "default", meaning shared tenancy. Allowed values are "default", "dedicated" and "host".
Metadata Settings
Configures the metadata options. See Configure IMDS for details.
http_endpoint
(string) - A string to enable or disable the IMDS endpoint for an instance. Defaults to enabled. Accepts either "enabled" or "disabled"http_tokens
(string) - A string to either set the use of IMDSv2 for the instance to optional or required. Defaults to "optional". Accepts either "optional" or "required"http_put_response_hop_limit
(int64) - A numerical value to set an upper limit for the amount of hops allowed when communicating with IMDS endpoints. Defaults to 1.instance_metadata_tags
(string) - A string to enable or disable access to instance tags from the instance metadata. Defaults to disabled. Access to instance metadata tags is available for commercial regions. For non-commercial regions please check availability before enabling. Accepts either "enabled" or "disabled"
Usage Example
HCL2
JSON
Enforce Instance Metadata Service v2
The Amazon builder has support for enforcing metadata service v2 (imdsv2) on a running instance and on the resulting AMI generated from a Packer build. To enable support for both there are two key attributes that must be defined.
HCL2
Session Manager Connections
Support for the AWS Systems Manager session manager lets users manage EC2 instances without the need to open inbound ports, or maintain bastion hosts. Session manager connectivity relies on the use of the session manager plugin to open a secure tunnel between the local machine and the remote instance. Once the tunnel has been created all SSH communication will be tunneled through SSM to the remote instance.
Note: Session manager connectivity is currently only implemented for the SSH communicator, not the WinRM Communicator.
To use the session manager as the connection interface for the SSH communicator you need to add the following configuration options to the Amazon builder options:
ssh_interface
: The ssh interface must be set to "session_manager". When using this option the builder will create an SSM tunnel to the configuredssh_port
(defaults to 22) on the remote host.iam_instance_profile
: A valid instance profile granting Systems Manager permissions to manage the remote instance is required in order for the aws ssm-agent to start and stop session connections. See below for more details on IAM instance profile for Systems Manager.
Optional
session_manager_port
: A local port on the host machine that should be used as the local end of the session tunnel to the remote host. If not specified Packer will find an available port to use.temporary_iam_instance_profile_policy_document
: Creates a temporary instance profile policy document to grant Systems Manager permissions to the Ec2 instance. This is an alternative to using an existingiam_instance_profile
.
HCL2 example:
JSON example:
Session Manager Plugin
Connectivity via the session manager requires the use of a session-manger-plugin, which needs to be installed alongside Packer, and an instance AMI that is capable of running the AWS ssm-agent - see About SSM Agent for details on supported AMIs.
In order for Packer to start and end sessions that connect you to your managed instances, you must first install the Session Manager plugin on your local machine. The plugin can be installed on supported versions of Microsoft Windows, macOS, Linux, and Ubuntu Server. Installation instructions for the session-manager-plugin
IAM instance profile for Systems Manager
By default Systems Manager doesn't have permission to perform actions on created instances so SSM access must be granted by creating an instance profile with the AmazonSSMManagedInstanceCore
policy. The instance profile can then be attached to any instance you wish to manage via the session-manager-plugin. See Adding System Manager instance profile for details on creating the required instance profile.
Permissions for Closing the Tunnel
To close the SSM tunnels created, this plugin relies on being able to call
DescribeInstanceStatus.
In case this is not possible you might see a Bad exit status
message in the logs.
The absence of this permission won't prevent you from building the AMI, and the error only means that packer is not able to close the tunnel gracefully.
Block Devices Configuration
Block devices can be nested in the ami_block_device_mappings or the launch_block_device_mappings array.
These will be attached when launching your instance. Your options here may vary depending on the type of VM you use.
Example use case:
The following mapping will tell Packer to encrypt the root volume of the build instance at launch using a specific non-default kms key:
HCL2 example:
JSON example:
Please note that the kms_key_id option in this example exists for launch_block_device_mappings but not ami_block_device_mappings.
Documentation for Block Devices Mappings can be found here: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html
Optional:
delete_on_termination
(bool) - 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 for every device in the block device mapping.encrypted
(boolean) - Indicates whether or not to encrypt the volume. By default, Packer will keep the encryption setting to what it was in the source image. Setting false will result in an unencrypted device, and true will result in an encrypted one.iops
(*int64) - The number of I/O operations per second (IOPS) that the volume supports. See the documentation on IOPs for more informationno_device
(bool) - Suppresses the specified device included in the block device mapping of the AMI.snapshot_id
(string) - The ID of the snapshot.throughput
(*int64) - The throughput for gp3 volumes, only valid for gp3 types See the documentation on Throughput for more informationvirtual_name
(string) - The virtual device name. See the documentation on Block Device Mapping for more information.Note: virtual_name only applies for ephemeral (instance) volumes. Any EBS-backed volume will have a
snapshot_id
instead.The volume virtual_name should be in the
ephemeral[0-23]
form, e.g. ephemeral1volume_type
(string) - The volume type. gp2 & gp3 for General Purpose (SSD) volumes, io1 & io2 for Provisioned IOPS (SSD) volumes, st1 for Throughput Optimized HDD, sc1 for Cold HDD, and standard for Magnetic volumes.volume_size
(int64) - The size of the volume, in GiB. Required if not specifying a snapshot_id.kms_key_id
(string) - ID, alias or ARN of the KMS key to use for boot volume encryption. This option exists for launch_block_device_mappings but not ami_block_device_mappings. The kms key id defined here only applies to the original build region; if the AMI gets copied to other regions, the volume in those regions will be encrypted by the default EBS KMS key. For valid formats see KmsKeyId in the AWS API docs - CopyImage This field is validated by Packer. When using an alias, you will have to prefix kms_key_id with alias/.
Communicator Configuration
Optional:
communicator
(string) - Packer currently supports three kinds of communicators:none
- No communicator will be used. If this is set, most provisioners also can't be used.ssh
- An SSH connection will be established to the machine. This is usually the default.winrm
- A WinRM connection will be established.
In addition to the above, some builders have custom communicators they can use. For example, the Docker builder has a "docker" communicator that uses
docker exec
anddocker cp
to execute scripts and copy files.pause_before_connecting
(duration string | ex: "1h5m2s") - We recommend that you enable SSH or WinRM as the very last step in your guest's bootstrap script, but sometimes you may have a race condition where you need Packer to wait before attempting to connect to your guest.If you end up in this situation, you can use the template option
pause_before_connecting
. By default, there is no pause. For example if you setpause_before_connecting
to10m
Packer will check whether it can connect, as normal. But once a connection attempt is successful, it will disconnect and then wait 10 minutes before connecting to the guest and beginning provisioning.
ssh_host
(string) - The address to SSH to. This usually is automatically configured by the builder.ssh_port
(int) - The port to connect to SSH. This defaults to22
.ssh_username
(string) - The username to connect to SSH with. Required if using SSH.ssh_password
(string) - A plaintext password to use to authenticate with SSH.ssh_ciphers
([]string) - This overrides the value of ciphers supported by default by Golang. The default value is [ "aes128-gcm@openssh.com", "chacha20-poly1305@openssh.com", "aes128-ctr", "aes192-ctr", "aes256-ctr", ]Valid options for ciphers include: "aes128-ctr", "aes192-ctr", "aes256-ctr", "aes128-gcm@openssh.com", "chacha20-poly1305@openssh.com", "arcfour256", "arcfour128", "arcfour", "aes128-cbc", "3des-cbc",
ssh_clear_authorized_keys
(bool) - If true, Packer will attempt to remove its temporary key from~/.ssh/authorized_keys
and/root/.ssh/authorized_keys
. This is a mostly cosmetic option, since Packer will delete the temporary private key from the host system regardless of whether this is set to true (unless the user has set the-debug
flag). Defaults to "false"; currently only works on guests withsed
installed.ssh_key_exchange_algorithms
([]string) - If set, Packer will override the value of key exchange (kex) algorithms supported by default by Golang. Acceptable values include: "curve25519-sha256@libssh.org", "ecdh-sha2-nistp256", "ecdh-sha2-nistp384", "ecdh-sha2-nistp521", "diffie-hellman-group14-sha1", and "diffie-hellman-group1-sha1".ssh_certificate_file
(string) - Path to user certificate used to authenticate with SSH. The~
can be used in path and will be expanded to the home directory of current user.ssh_pty
(bool) - Iftrue
, a PTY will be requested for the SSH connection. This defaults tofalse
.ssh_timeout
(duration string | ex: "1h5m2s") - The time to wait for SSH to become available. Packer uses this to determine when the machine has booted so this is usually quite long. Example value:10m
. This defaults to5m
, unlessssh_handshake_attempts
is set.ssh_disable_agent_forwarding
(bool) - If true, SSH agent forwarding will be disabled. Defaults tofalse
.ssh_handshake_attempts
(int) - The number of handshakes to attempt with SSH once it can connect. This defaults to10
, unless assh_timeout
is set.ssh_bastion_host
(string) - A bastion host to use for the actual SSH connection.ssh_bastion_port
(int) - The port of the bastion host. Defaults to22
.ssh_bastion_agent_auth
(bool) - Iftrue
, the local SSH agent will be used to authenticate with the bastion host. Defaults tofalse
.ssh_bastion_username
(string) - The username to connect to the bastion host.ssh_bastion_password
(string) - The password to use to authenticate with the bastion host.ssh_bastion_interactive
(bool) - Iftrue
, the keyboard-interactive used to authenticate with bastion host.ssh_bastion_private_key_file
(string) - Path to a PEM encoded private key file to use to authenticate with the bastion host. The~
can be used in path and will be expanded to the home directory of current user.ssh_bastion_certificate_file
(string) - Path to user certificate used to authenticate with bastion host. The~
can be used in path and will be expanded to the home directory of current user.ssh_file_transfer_method
(string) -scp
orsftp
- How to transfer files, Secure copy (default) or SSH File Transfer Protocol.NOTE: Guests using Windows with Win32-OpenSSH v9.1.0.0p1-Beta, scp (the default protocol for copying data) returns a a non-zero error code since the MOTW cannot be set, which cause any file transfer to fail. As a workaround you can override the transfer protocol with SFTP instead
ssh_file_transfer_method = "sftp"
.ssh_proxy_host
(string) - A SOCKS proxy host to use for SSH connectionssh_proxy_port
(int) - A port of the SOCKS proxy. Defaults to1080
.ssh_proxy_username
(string) - The optional username to authenticate with the proxy server.ssh_proxy_password
(string) - The optional password to use to authenticate with the proxy server.ssh_keep_alive_interval
(duration string | ex: "1h5m2s") - How often to send "keep alive" messages to the server. Set to a negative value (-1s
) to disable. Example value:10s
. Defaults to5s
.ssh_read_write_timeout
(duration string | ex: "1h5m2s") - The amount of time to wait for a remote command to end. This might be useful if, for example, packer hangs on a connection after a reboot. Example:5m
. Disabled by default.ssh_remote_tunnels
([]string) -ssh_local_tunnels
([]string) -
temporary_key_pair_type
(string) -dsa
|ecdsa
|ed25519
|rsa
( the default )Specifies the type of key to create. The possible values are 'dsa', 'ecdsa', 'ed25519', or 'rsa'.
NOTE: DSA is deprecated and no longer recognized as secure, please consider other alternatives like RSA or ED25519.
temporary_key_pair_bits
(int) - Specifies the number of bits in the key to create. For RSA keys, the minimum size is 1024 bits and the default is 4096 bits. Generally, 3072 bits is considered sufficient. DSA keys must be exactly 1024 bits as specified by FIPS 186-2. For ECDSA keys, bits determines the key length by selecting from one of three elliptic curve sizes: 256, 384 or 521 bits. Attempting to use bit lengths other than these three values for ECDSA keys will fail. Ed25519 keys have a fixed length and bits will be ignored.NOTE: DSA is deprecated and no longer recognized as secure as specified by FIPS 186-5, please consider other alternatives like RSA or ED25519.
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 the remote. By default, this is blank, and Packer will generate a temporary keypair unlessssh_password
is used.ssh_private_key_file
orssh_agent_auth
must be specified whenssh_keypair_name
is utilized.
ssh_private_key_file
(string) - Path to a PEM encoded private key file to use to authenticate with SSH. The~
can be used in path and will be expanded to the home directory of current user.
ssh_agent_auth
(bool) - 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 ofssh_password
andssh_private_key_file
will be ignored. The environment variableSSH_AUTH_SOCK
must be set for this option to work properly.
Deregistration Protection Options
DeregistrationProtectionOptions lets users set AMI deregistration protection
HCL2 example:
JSON Example:
Protect an AMI from deregistration When deregistration protection is enabled, the AMI cannot be deregistered. To allow the AMI to be deregistered, you must first disable deregistration protection.
enabled
(bool) - Enable AMI deregistration protection. To allow the AMI to be deregistered, you must first disable deregistration protection.with_cooldown
(bool) - When you turn on deregistration protection on an AMI, you have the option to include a 24-hour cooldown period. This cooldown period is the time during which deregistration protection remains in effect after you turn it off. During this cooldown period, the AMI can’t be deregistered. When the cooldown period ends, the AMI can be deregistered.
Basic Example
Here is a basic example. You will need to provide access keys, and may need to change the AMI IDs according to what images exist at the time the template is run:
HCL2
JSON
Note: Packer can also read the access key and secret access key directly from environmental variables instead of being set as user 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 or for Windows.
Fast Launch Config
FastLaunchConfig is the configuration for setting up fast-launch for Windows AMIs
NOTE: requires the Windows image to be sysprep'd to enable fast-launch. See the AWS docs for more information: https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/win-ami-config-fast-launch.html
Optional:
enable_fast_launch
(bool) - Configure fast-launch for Windows AMIstemplate_id
(string) - The ID of the launch template to use for fast launch for the main AMI.This cannot be specified in conjunction with the template name.
If no template is specified, the default launch template will be used, as specified in the AWS docs.
If you copy the AMI to other regions, this option should not be used, use instead the
fast_launch_template_config
option.template_name
(string) - The name of the launch template to use for fast launch for the main AMI.This cannot be specified in conjunction with the template ID.
If no template is specified, the default launch template will be used, as specified in the AWS docs.
If you copy the AMI to other regions, this option should not be used, use instead the
fast_launch_template_config
option.template_version
(int) - The version of the launch template to use for fast launch for the main AMI.If unspecified, and a template is referenced, this will default to the latest version available for the template.
If you copy the AMI to other regions, this option should not be used, use instead the
fast_launch_template_config
option.region_launch_templates
([]FastLaunchTemplateConfig) - RegionLaunchTemplates is the list of launch templates per region.This should be specified if you want to use a custom launch template for your fast-launched images, and you are copying the image to other regions.
All regions don't need a launch template configuration, but for each that don't have a launch template specified, AWS will pick a default one for that purpose.
For information about each entry, refer to the Fast Launch Template Config documentation.
max_parallel_launches
(int) - Maximum number of instances to launch for creating pre-provisioned snapshotsIf specified, must be a minimum of
6
target_resource_count
(int) - The number of snapshots to pre-provision for later launching windows instances from the resulting fast-launch AMI.If unspecified, this will create the default number of snapshots (as of march 2023, this defaults to 5 on AWS)
Fast Launch Template Config
region
(string) - The region in which to find the launch template to use
Optional:
enable_fast_launch
(boolean) - Enable fast launch allows you to disable fast launch settings on the region level.If unset, the default region behavior will be assumed - i.e. either use the globally specified template ID/name (if specified), or AWS will set it for you.
Using other fast launch options, while unset, will imply enable_fast_launch to be true.
If this is explicitly set to
false
fast-launch will be disabled for the specified region and all other options besides region will be ignored.template_id
(string) - The ID of the launch template to use for the fast launchThis cannot be specified in conjunction with the template name.
If no template is specified, the default launch template will be used, as specified in the AWS docs.
template_name
(string) - The name of the launch template to use for fast launchThis cannot be specified in conjunction with the template ID.
If no template is specified, the default launch template will be used, as specified in the AWS docs.
template_version
(int) - The version of the launch template to useIf unspecified, and a template is referenced, this will default to the latest version available for the template.
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.
AMI Block Device Mappings Example
Here is an example using the optional AMI block device mappings. Our
configuration of launch_block_device_mappings
will expand the root volume
(/dev/sda
) to 40gb during the build (up from the default of 8gb). With
ami_block_device_mappings
AWS will attach additional volumes /dev/sdb
and
/dev/sdc
when we boot a new instance of our AMI.
HCL2
JSON
The above build template is functional assuming you have set the environment variables AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.
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. Packer will attempt to
clean up all residual volumes that are not designated by the user to remain
after termination. If you need to preserve those source volumes, you can
overwrite the termination setting by setting delete_on_termination
to false
in the launch_block_device_mappings
block for the device.
Build template data
In configuration directives marked as a template engine above, the following variables are available:
BuildRegion
- The region (for exampleeu-central-1
) where Packer is building the AMI.SourceAMI
- The source AMI ID (for exampleami-a2412fcd
) used to build the AMI.SourceAMICreationDate
- The source AMI creation date (for example"2020-05-14T19:26:34.000Z"
).SourceAMIName
- The source AMI Name (for exampleubuntu/images/ebs-ssd/ubuntu-xenial-16.04-amd64-server-20180306
) used to build the AMI.SourceAMIOwner
- The source AMI owner ID.SourceAMIOwnerName
- The source AMI owner alias/name (for exampleamazon
).SourceAMITags
- The source AMI Tags, as amap[string]string
object.
Build Shared Information Variables
This builder generates data that are shared with provisioner and post-processor via build function of template engine for JSON and contextual variables for HCL2.
The generated variables available for this builder are:
BuildRegion
- The region (for exampleeu-central-1
) where Packer is building the AMI.SourceAMI
- The source AMI ID (for exampleami-a2412fcd
) used to build the AMI.SourceAMICreationDate
- The source AMI creation date (for example"2020-05-14T19:26:34.000Z"
).SourceAMIName
- The source AMI Name (for exampleubuntu/images/ebs-ssd/ubuntu-xenial-16.04-amd64-server-20180306
) used to build the AMI.SourceAMIOwner
- The source AMI owner ID.SourceAMIOwnerName
- The source AMI owner alias/name (for exampleamazon
).
Usage example:
HCL2
JSON
Tag Example
Here is an example using the optional AMI tags. This will add the tags
OS_Version
and Release
to the finished AMI. As before, you will need to
provide your access keys, and may need to change the source AMI ID based on
what images exist when this template is run:
HCL2
JSON
Connecting to Windows instances using WinRM
If you want to launch a Windows instance and connect using WinRM, you will need to configure WinRM on that instance. The following is a basic powershell script that can be supplied to AWS using the "user_data_file" option. It enables WinRM via HTTPS on port 5986, and creates a self-signed certificate to use to connect. If you are using a certificate from a CA, rather than creating a self-signed certificate, you can omit the "winrm_insecure" option mentioned below.
autogenerated_password_https_bootstrap.txt
You'll notice that this config does not define a user or password; instead, Packer will ask AWS to provide a random password that it generates automatically. The following config will work with the above template:
HCL2
JSON
Windows 2016 Sysprep Commands - For Amazon Windows AMIs Only
For Amazon Windows 2016 AMIs it is necessary to run Sysprep commands which can be easily added to the provisioner section.
HCL2
JSON
Which SSH Options to use:
This chart breaks down what Packer does if you set any of the below SSH options:
ssh_password | ssh_private_key_file | ssh_keypair_name | temporary_key_pair_name | Packer will... |
---|---|---|---|---|
X | - | - | - | ssh authenticating with username and given password |
- | X | - | - | ssh authenticating with private key file |
- | X | X | - | ssh authenticating with given private key file and "attaching" the keypair to the instance |
- | - | - | X | Create a temporary ssh keypair with a particular name, clean it up |
- | - | - | - | Create a temporary ssh keypair with a default name, clean it up |