salt/doc/topics/cloud/aws.rst

============================
Getting Started With AWS EC2
============================

Amazon EC2 is a very widely used public cloud platform and one of the core
platforms Salt Cloud has been built to support.

Previously, the suggested provider for AWS EC2 was the ``aws`` provider. This
has been deprecated in favor of the ``ec2`` provider. Configuration using the
old ``aws`` provider will still function, but that driver is no longer in
active development.


Dependencies
============
This driver requires the Python ``requests`` library to be installed.


Configuration
=============
The following example illustrates some of the options that can be set. These
parameters are discussed in more detail below.

.. code-block:: yaml

    # Note: This example is for /etc/salt/cloud.providers or any file in the
    # /etc/salt/cloud.providers.d/ directory.

    my-ec2-southeast-public-ips:
      # Set up the location of the salt master
      #
      minion:
        master: saltmaster.example.com

      # Set up grains information, which will be common for all nodes
      # using this provider
      grains:
        node_type: broker
        release: 1.0.1

      # Specify whether to use public or private IP for deploy script.
      #
      # Valid options are:
      #     private_ips - The salt-cloud command is run inside the EC2
      #     public_ips - The salt-cloud command is run outside of EC2
      #
      ssh_interface: public_ips

      # Optionally configure the Windows credential validation number of
      # retries and delay between retries.  This defaults to 10 retries
      # with a one second delay betwee retries
      win_deploy_auth_retries: 10
      win_deploy_auth_retry_delay: 1
      
      # Set the EC2 access credentials (see below)
      #
      id: 'use-instance-role-credentials'
      key: 'use-instance-role-credentials'

      # Make sure this key is owned by root with permissions 0400.
      #
      private_key: /etc/salt/my_test_key.pem
      keyname: my_test_key
      securitygroup: default

      # Optionally configure default region
      # Use salt-cloud --list-locations <provider> to obtain valid regions
      #
      location: ap-southeast-1
      availability_zone: ap-southeast-1b

      # Configure which user to use to run the deploy script. This setting is
      # dependent upon the AMI that is used to deploy. It is usually safer to
      # configure this individually in a profile, than globally. Typical users
      # are:
      #
      # Amazon Linux -> ec2-user
      # RHEL         -> ec2-user
      # CentOS       -> ec2-user
      # Ubuntu       -> ubuntu
      #
      ssh_username: ec2-user

      # Optionally add an IAM profile
      iam_profile: 'arn:aws:iam::123456789012:instance-profile/ExampleInstanceProfile'

      driver: ec2


    my-ec2-southeast-private-ips:
      # Set up the location of the salt master
      #
      minion:
        master: saltmaster.example.com

      # Specify whether to use public or private IP for deploy script.
      #
      # Valid options are:
      #     private_ips - The salt-master is also hosted with EC2
      #     public_ips - The salt-master is hosted outside of EC2
      #
      ssh_interface: private_ips

      # Optionally configure the Windows credential validation number of
      # retries and delay between retries.  This defaults to 10 retries
      # with a one second delay betwee retries
      win_deploy_auth_retries: 10
      win_deploy_auth_retry_delay: 1
      
      # Set the EC2 access credentials (see below)
      #
      id: 'use-instance-role-credentials'
      key: 'use-instance-role-credentials'

      # Make sure this key is owned by root with permissions 0400.
      #
      private_key: /etc/salt/my_test_key.pem
      keyname: my_test_key

      # This one should NOT be specified if VPC was not configured in AWS to be
      # the default. It might cause an error message which sais that network
      # interfaces and an instance-level security groups may not be specified
      # on the same request.
      #
      securitygroup: default

      # Optionally configure default region
      #
      location: ap-southeast-1
      availability_zone: ap-southeast-1b

      # Configure which user to use to run the deploy script. This setting is
      # dependent upon the AMI that is used to deploy. It is usually safer to
      # configure this individually in a profile, than globally. Typical users
      # are:
      #
      # Amazon Linux -> ec2-user
      # RHEL         -> ec2-user
      # CentOS       -> ec2-user
      # Ubuntu       -> ubuntu
      #
      ssh_username: ec2-user

      # Optionally add an IAM profile
      iam_profile: 'my other profile name'

      driver: ec2


Access Credentials
==================
The ``id`` and ``key`` settings may be found in the Security Credentials area
of the AWS Account page:

https://portal.aws.amazon.com/gp/aws/securityCredentials

Both are located in the Access Credentials area of the page, under the Access
Keys tab. The ``id`` setting is labeled Access Key ID, and the ``key`` setting
is labeled Secret Access Key.

Note: if either ``id`` or ``key`` is set to 'use-instance-role-credentials' it is
assumed that Salt is running on an AWS instance, and the instance role
credentials will be retrieved and used.  Since both the ``id`` and ``key`` are
required parameters for the AWS ec2 provider, it is recommended to set both
to 'use-instance-role-credentials' for this functionality.

A "static" and "permanent" Access Key ID and Secret Key can be specified,
but this is not recommended.  Instance role keys are rotated on a regular
basis, and are the recommended method of specifying AWS credentials.

Windows Deploy Timeouts
=======================
For Windows instances, it may take longer than normal for the instance to be
ready.  In these circumstances, the provider configuration can be configured
with a ``win_deploy_auth_retries`` and/or a ``win_deploy_auth_retry_delay``
setting, which default to 10 retries and a one second delay between retries.
These retries and timeouts relate to validating the Administrator password
once AWS provides the credentials via the AWS API.


Windows Deploy Timeouts
=======================
For Windows instances, it may take longer than normal for the instance to be
ready.  In these circumstances, the provider configuration can be configured
with a ``win_deploy_auth_retries`` and/or a ``win_deploy_auth_retry_delay``
setting, which default to 10 retries and a one second delay between retries.
These retries and timeouts relate to validating the Administrator password
once AWS provides the credentials via the AWS API.


Key Pairs
=========
In order to create an instance with Salt installed and configured, a key pair
will need to be created. This can be done in the EC2 Management Console, in the
Key Pairs area. These key pairs are unique to a specific region. Keys in the
us-east-1 region can be configured at:

https://console.aws.amazon.com/ec2/home?region=us-east-1#s=KeyPairs

Keys in the us-west-1 region can be configured at

https://console.aws.amazon.com/ec2/home?region=us-west-1#s=KeyPairs

...and so on. When creating a key pair, the browser will prompt to download a
pem file. This file must be placed in a directory accessible by Salt Cloud,
with permissions set to either 0400 or 0600.


Security Groups
===============
An instance on EC2 needs to belong to a security group. Like key pairs, these
are unique to a specific region. These are also configured in the EC2
Management Console. Security groups for the us-east-1 region can be configured
at:

https://console.aws.amazon.com/ec2/home?region=us-east-1#s=SecurityGroups

...and so on.

A security group defines firewall rules which an instance will adhere to. If
the salt-master is configured outside of EC2, the security group must open the
SSH port (usually port 22) in order for Salt Cloud to install Salt.


IAM Profile
===========
Amazon EC2 instances support the concept of an `instance profile`_, which
is a logical container for the IAM role. At the time that you launch an EC2
instance, you can associate the instance with an instance profile, which in
turn corresponds to the IAM role. Any software that runs on the EC2 instance
is able to access AWS using the permissions associated with the IAM role.

Scaffolding the profile is a 2-step configuration process:

1. Configure an IAM Role from the `IAM Management Console`_.
2. Attach this role to a new profile. It can be done with the `AWS CLI`_:

    .. code-block:: bash

        > aws iam create-instance-profile --instance-profile-name PROFILE_NAME
        > aws iam add-role-to-instance-profile --instance-profile-name PROFILE_NAME --role-name ROLE_NAME

Once the profile is created, you can use the **PROFILE_NAME** to configure
your cloud profiles.

.. _`IAM Management Console`: https://console.aws.amazon.com/iam/home?#roles
.. _`AWS CLI`: http://docs.aws.amazon.com/cli/latest/index.html
.. _`instance profile`: http://docs.aws.amazon.com/IAM/latest/UserGuide/instance-profiles.html


Cloud Profiles
==============
Set up an initial profile at ``/etc/salt/cloud.profiles``:

.. code-block:: yaml

    base_ec2_private:
      provider: my-ec2-southeast-private-ips
      image: ami-e565ba8c
      size: t1.micro
      ssh_username: ec2-user

    base_ec2_public:
      provider: my-ec2-southeast-public-ips
      image: ami-e565ba8c
      size: t1.micro
      ssh_username: ec2-user

    base_ec2_db:
      provider: my-ec2-southeast-public-ips
      image: ami-e565ba8c
      size: m1.xlarge
      ssh_username: ec2-user
      volumes:
        - { size: 10, device: /dev/sdf }
        - { size: 10, device: /dev/sdg, type: io1, iops: 1000 }
        - { size: 10, device: /dev/sdh, type: io1, iops: 1000 }
      # optionally add tags to profile:
      tag: {'Environment': 'production', 'Role': 'database'}
      # force grains to sync after install
      sync_after_install: grains

    base_ec2_vpc:
      provider: my-ec2-southeast-public-ips
      image: ami-a73264ce
      size: m1.xlarge
      ssh_username: ec2-user
      script:  /etc/salt/cloud.deploy.d/user_data.sh
      network_interfaces:
        - DeviceIndex: 0
          PrivateIpAddresses:
            - Primary: True
          #auto assign public ip (not EIP)
          AssociatePublicIpAddress: True
          SubnetId: subnet-813d4bbf
          SecurityGroupId:
            - sg-750af413
      volumes:
        - { size: 10, device: /dev/sdf }
        - { size: 10, device: /dev/sdg, type: io1, iops: 1000 }
        - { size: 10, device: /dev/sdh, type: io1, iops: 1000 }
      del_root_vol_on_destroy: True
      del_all_vol_on_destroy: True
      tag: {'Environment': 'production', 'Role': 'database'}
      sync_after_install: grains


The profile can now be realized with a salt command:

.. code-block:: bash

    # salt-cloud -p base_ec2 ami.example.com
    # salt-cloud -p base_ec2_public ami.example.com
    # salt-cloud -p base_ec2_private ami.example.com


This will create an instance named ``ami.example.com`` in EC2. The minion that
is installed on this instance will have an ``id`` of ``ami.example.com``. If
the command was executed on the salt-master, its Salt key will automatically be
signed on the master.

Once the instance has been created with salt-minion installed, connectivity to
it can be verified with Salt:

.. code-block:: bash

    # salt 'ami.example.com' test.ping


Required Settings
=================
The following settings are always required for EC2:

.. code-block:: yaml

    # Set the EC2 login data
    my-ec2-config:
      id: HJGRYCILJLKJYG
      key: 'kdjgfsgm;woormgl/aserigjksjdhasdfgn'
      keyname: test
      securitygroup: quick-start
      private_key: /root/test.pem
      driver: ec2


Optional Settings
=================

EC2 allows a location to be set for servers to be deployed in. Availability
zones exist inside regions, and may be added to increase specificity.

.. code-block:: yaml

    my-ec2-config:
      # Optionally configure default region
      location: ap-southeast-1
      availability_zone: ap-southeast-1b


EC2 instances can have a public or private IP, or both. When an instance is
deployed, Salt Cloud needs to log into it via SSH to run the deploy script.
By default, the public IP will be used for this. If the salt-cloud command is
run from another EC2 instance, the private IP should be used.

.. code-block:: yaml

    my-ec2-config:
      # Specify whether to use public or private IP for deploy script
      # private_ips or public_ips
      ssh_interface: public_ips


Many EC2 instances do not allow remote access to the root user by default.
Instead, another user must be used to run the deploy script using sudo. Some
common usernames include ec2-user (for Amazon Linux), ubuntu (for Ubuntu
instances), admin (official Debian) and bitnami (for images provided by
Bitnami).

.. code-block:: yaml

    my-ec2-config:
      # Configure which user to use to run the deploy script
      ssh_username: ec2-user


Multiple usernames can be provided, in which case Salt Cloud will attempt to
guess the correct username. This is mostly useful in the main configuration
file:

.. code-block:: yaml

    my-ec2-config:
      ssh_username:
        - ec2-user
        - ubuntu
        - admin
        - bitnami


Multiple security groups can also be specified in the same fashion:

.. code-block:: yaml

    my-ec2-config:
      securitygroup:
        - default
        - extra

Your instances may optionally make use of EC2 Spot Instances. The
following example will request that spot instances be used and your
maximum bid will be $0.10. Keep in mind that different spot prices
may be needed based on the current value of the various EC2 instance
sizes. You can check current and past spot instance pricing via the
EC2 API or AWS Console.

.. code-block:: yaml

    my-ec2-config:
      spot_config:
        spot_price: 0.10

By default, the spot instance type is set to 'one-time', meaning it will
be launched and, if it's ever terminated for whatever reason, it will not
be recreated. If you would like your spot instances to be relaunched after
a termination (by your or AWS), set the ``type`` to 'persistent'.

NOTE: Spot instances are a great way to save a bit of money, but you do
run the risk of losing your spot instances if the current price for the
instance size goes above your maximum bid.

The following parameters may be set in the cloud configuration file to
control various aspects of the spot instance launching:

* ``wait_for_spot_timeout``: seconds to wait before giving up on spot instance
  launch (default=600)
* ``wait_for_spot_interval``: seconds to wait in between polling requests to
  determine if a spot instance is available (default=30)
* ``wait_for_spot_interval_multiplier``: a multiplier to add to the interval in
  between requests, which is useful if AWS is throttling your requests
  (default=1)
* ``wait_for_spot_max_failures``: maximum number of failures before giving up
  on launching your spot instance (default=10)

If you find that you're being throttled by AWS while polling for spot
instances, you can set the following in your core cloud configuration
file that will double the polling interval after each request to AWS.

.. code-block:: yaml

    wait_for_spot_interval: 1
    wait_for_spot_interval_multiplier: 2

See the `AWS Spot Instances`_ documentation for more information.


Block device mappings enable you to specify additional EBS volumes or instance
store volumes when the instance is launched. This setting is also available on
each cloud profile. Note that the number of instance stores varies by instance
type.  If more mappings are provided than are supported by the instance type,
mappings will be created in the order provided and additional mappings will be
ignored. Consult the `AWS documentation`_ for a listing of the available
instance stores, and device names.

.. code-block:: yaml

    my-ec2-config:
      block_device_mappings:
        - DeviceName: /dev/sdb
          VirtualName: ephemeral0
        - DeviceName: /dev/sdc
          VirtualName: ephemeral1

You can also use block device mappings to change the size of the root device at the
provisioning time. For example, assuming the root device is '/dev/sda', you can set
its size to 100G by using the following configuration.

.. code-block:: yaml

    my-ec2-config:
      block_device_mappings:
        - DeviceName: /dev/sda
          Ebs.VolumeSize: 100
          Ebs.VolumeType: gp2
          Ebs.SnapshotId: dummy0

Existing EBS volumes may also be attached (not created) to your instances or
you can create new EBS volumes based on EBS snapshots. To simply attach an
existing volume use the ``volume_id`` parameter.

.. code-block:: yaml

    device: /dev/xvdj
    volume_id: vol-12345abcd

Or, to create a volume from an EBS snapshot, use the ``snapshot`` parameter.

.. code-block:: yaml

    device: /dev/xvdj
    snapshot: snap-abcd12345

Note that ``volume_id`` will take precedence over the ``snapshot`` parameter.

Tags can be set once an instance has been launched.

.. code-block:: yaml

    my-ec2-config:
        tag:
            tag0: value
            tag1: value

.. _`AWS documentation`: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html
.. _`AWS Spot Instances`: http://aws.amazon.com/ec2/purchasing-options/spot-instances/

Modify EC2 Tags
===============
One of the features of EC2 is the ability to tag resources. In fact, under the
hood, the names given to EC2 instances by salt-cloud are actually just stored
as a tag called Name. Salt Cloud has the ability to manage these tags:

.. code-block:: bash

    salt-cloud -a get_tags mymachine
    salt-cloud -a set_tags mymachine tag1=somestuff tag2='Other stuff'
    salt-cloud -a del_tags mymachine tag1,tag2,tag3

It is possible to manage tags on any resource in EC2 with a Resource ID, not
just instances:

.. code-block:: bash

    salt-cloud -f get_tags my_ec2 resource_id=af5467ba
    salt-cloud -f set_tags my_ec2 resource_id=af5467ba tag1=somestuff
    salt-cloud -f del_tags my_ec2 resource_id=af5467ba tag1,tag2,tag3


Rename EC2 Instances
====================
As mentioned above, EC2 instances are named via a tag. However, renaming an
instance by renaming its tag will cause the salt keys to mismatch. A rename
function exists which renames both the instance, and the salt keys.

.. code-block:: bash

    salt-cloud -a rename mymachine newname=yourmachine


EC2 Termination Protection
==========================
EC2 allows the user to enable and disable termination protection on a specific
instance. An instance with this protection enabled cannot be destroyed.

.. code-block:: bash

    salt-cloud -a enable_term_protect mymachine
    salt-cloud -a disable_term_protect mymachine


Rename on Destroy
=================
When instances on EC2 are destroyed, there will be a lag between the time that
the action is sent, and the time that Amazon cleans up the instance. During
this time, the instance still retails a Name tag, which will cause a collision
if the creation of an instance with the same name is attempted before the
cleanup occurs. In order to avoid such collisions, Salt Cloud can be configured
to rename instances when they are destroyed. The new name will look something
like:

.. code-block:: bash

    myinstance-DEL20f5b8ad4eb64ed88f2c428df80a1a0c


In order to enable this, add rename_on_destroy line to the main
configuration file:

.. code-block:: yaml

    my-ec2-config:
      rename_on_destroy: True


Listing Images
==============
Normally, images can be queried on a cloud provider by passing the
``--list-images`` argument to Salt Cloud. This still holds true for EC2:

.. code-block:: bash

    salt-cloud --list-images my-ec2-config

However, the full list of images on EC2 is extremely large, and querying all of
the available images may cause Salt Cloud to behave as if frozen. Therefore,
the default behavior of this option may be modified, by adding an ``owner``
argument to the provider configuration:

.. code-block:: yaml

    owner: aws-marketplace

The possible values for this setting are ``amazon``, ``aws-marketplace``,
``self``, ``<AWS account ID>`` or ``all``. The default setting is ``amazon``.
Take note that ``all`` and ``aws-marketplace`` may cause Salt Cloud to appear
as if it is freezing, as it tries to handle the large amount of data.

It is also possible to perform this query using different settings without
modifying the configuration files. To do this, call the ``avail_images``
function directly:

.. code-block:: bash

    salt-cloud -f avail_images my-ec2-config owner=aws-marketplace


EC2 Images
==========
The following are lists of available AMI images, generally sorted by OS. These
lists are on 3rd-party websites, are not managed by Salt Stack in any way. They
are provided here as a reference for those who are interested, and contain no
warranty (express or implied) from anyone affiliated with Salt Stack. Most of
them have never been used, much less tested, by the Salt Stack team.

* `Arch Linux`__

.. __: https://wiki.archlinux.org/index.php/Arch_Linux_AMIs_for_Amazon_Web_Services

* `FreeBSD`__

.. __: http://www.daemonology.net/freebsd-on-ec2/

* `Fedora`__

.. __: https://fedoraproject.org/wiki/Cloud_images

* `CentOS`__

.. __: http://wiki.centos.org/Cloud/AWS

* `Ubuntu`__

.. __: http://cloud-images.ubuntu.com/locator/ec2/

* `Debian`__

.. __: https://wiki.debian.org/Cloud/AmazonEC2Image

* `OmniOS`__

.. __: http://omnios.omniti.com/wiki.php/Installation#IntheCloud

* `All Images on Amazon`__

.. __: https://aws.amazon.com/marketplace


show_image
==========
This is a function that describes an AMI on EC2. This will give insight as to
the defaults that will be applied to an instance using a particular AMI.

.. code-block:: bash

    $ salt-cloud -f show_image ec2 image=ami-fd20ad94


show_instance
=============
This action is a thin wrapper around ``--full-query``, which displays details on a
single instance only. In an environment with several machines, this will save a
user from having to sort through all instance data, just to examine a single
instance.

.. code-block:: bash

    $ salt-cloud -a show_instance myinstance


ebs_optimized
=============
This argument enables switching of the EbsOptimized setting which default
to 'false'. Indicates whether the instance is optimized for EBS I/O. This
optimization provides dedicated throughput to Amazon EBS and an optimized
configuration stack to provide optimal Amazon EBS I/O performance. This
optimization isn't available with all instance types. Additional usage
charges apply when using an EBS-optimized instance.

This setting can be added to the profile or map file for an instance.

If set to True, this setting will enable an instance to be EbsOptimized

.. code-block:: yaml

   ebs_optimized: True

This can also be set as a cloud provider setting in the EC2 cloud
configuration:

.. code-block:: yaml

   my-ec2-config:
     ebs_optimized: True


del_root_vol_on_destroy
=======================
This argument overrides the default DeleteOnTermination setting in the AMI for
the EBS root volumes for an instance. Many AMIs contain 'false' as a default,
resulting in orphaned volumes in the EC2 account, which may unknowingly be
charged to the account. This setting can be added to the profile or map file
for an instance.

If set, this setting will apply to the root EBS volume

.. code-block:: yaml

    del_root_vol_on_destroy: True


This can also be set as a cloud provider setting in the EC2 cloud
configuration:

.. code-block:: yaml

    my-ec2-config:
      del_root_vol_on_destroy: True


del_all_vols_on_destroy
=======================
This argument overrides the default DeleteOnTermination setting in the AMI for
the not-root EBS volumes for an instance. Many AMIs contain 'false' as a
default, resulting in orphaned volumes in the EC2 account, which may
unknowingly be charged to the account. This setting can be added to the profile
or map file for an instance.

If set, this setting will apply to any (non-root) volumes that were created
by salt-cloud using the 'volumes' setting.

The volumes will not be deleted under the following conditions
* If a volume is detached before terminating the instance
* If a volume is created without this setting and attached to the instance

.. code-block:: yaml

    del_all_vols_on_destroy: True


This can also be set as a cloud provider setting in the EC2 cloud
configuration:

.. code-block:: yaml

    my-ec2-config:
      del_all_vols_on_destroy: True


The setting for this may be changed on all volumes of an existing instance
using one of the following commands:

.. code-block:: bash

    salt-cloud -a delvol_on_destroy myinstance
    salt-cloud -a keepvol_on_destroy myinstance
    salt-cloud -a show_delvol_on_destroy myinstance

The setting for this may be changed on a volume on an existing instance
using one of the following commands:

.. code-block:: bash

    salt-cloud -a delvol_on_destroy myinstance device=/dev/sda1
    salt-cloud -a delvol_on_destroy myinstance volume_id=vol-1a2b3c4d
    salt-cloud -a keepvol_on_destroy myinstance device=/dev/sda1
    salt-cloud -a keepvol_on_destroy myinstance volume_id=vol-1a2b3c4d
    salt-cloud -a show_delvol_on_destroy myinstance device=/dev/sda1
    salt-cloud -a show_delvol_on_destroy myinstance volume_id=vol-1a2b3c4d


EC2 Termination Protection
==========================

EC2 allows the user to enable and disable termination protection on a specific
instance. An instance with this protection enabled cannot be destroyed. The EC2
driver adds a show_term_protect action to the regular EC2 functionality.

.. code-block:: bash

    salt-cloud -a show_term_protect mymachine
    salt-cloud -a enable_term_protect mymachine
    salt-cloud -a disable_term_protect mymachine


Alternate Endpoint
==================
Normally, EC2 endpoints are build using the region and the service_url. The
resulting endpoint would follow this pattern:

.. code-block:: bash

    ec2.<region>.<service_url>


This results in an endpoint that looks like:

.. code-block:: bash

    ec2.us-east-1.amazonaws.com


There are other projects that support an EC2 compatibility layer, which this
scheme does not account for. This can be overridden by specifying the endpoint
directly in the main cloud configuration file:

.. code-block:: yaml

    my-ec2-config:
      endpoint: myendpoint.example.com:1138/services/Cloud


Volume Management
=================
The EC2 driver has several functions and actions for management of EBS volumes.


Creating Volumes
----------------
A volume may be created, independent of an instance. A zone must be specified.
A size or a snapshot may be specified (in GiB). If neither is given, a default
size of 10 GiB will be used. If a snapshot is given, the size of the snapshot
will be used.

.. code-block:: bash

    salt-cloud -f create_volume ec2 zone=us-east-1b
    salt-cloud -f create_volume ec2 zone=us-east-1b size=10
    salt-cloud -f create_volume ec2 zone=us-east-1b snapshot=snap12345678
    salt-cloud -f create_volume ec2 size=10 type=standard
    salt-cloud -f create_volume ec2 size=10 type=io1 iops=1000


Attaching Volumes
-----------------
Unattached volumes may be attached to an instance. The following values are
required; name or instance_id, volume_id, and device.

.. code-block:: bash

    salt-cloud -a attach_volume myinstance volume_id=vol-12345 device=/dev/sdb1


Show a Volume
-------------
The details about an existing volume may be retrieved.

.. code-block:: bash

    salt-cloud -a show_volume myinstance volume_id=vol-12345
    salt-cloud -f show_volume ec2 volume_id=vol-12345


Detaching Volumes
-----------------
An existing volume may be detached from an instance.

.. code-block:: bash

    salt-cloud -a detach_volume myinstance volume_id=vol-12345


Deleting Volumes
----------------
A volume that is not attached to an instance may be deleted.

.. code-block:: bash

    salt-cloud -f delete_volume ec2 volume_id=vol-12345


Managing Key Pairs
==================
The EC2 driver has the ability to manage key pairs.


Creating a Key Pair
-------------------
A key pair is required in order to create an instance. When creating a key pair
with this function, the return data will contain a copy of the private key.
This private key is not stored by Amazon, will not be obtainable past this
point, and should be stored immediately.

.. code-block:: bash

    salt-cloud -f create_keypair ec2 keyname=mykeypair


Show a Key Pair
---------------
This function will show the details related to a key pair, not including the
private key itself (which is not stored by Amazon).

.. code-block:: bash

    salt-cloud -f show_keypair ec2 keyname=mykeypair


Delete a Key Pair
-----------------
This function removes the key pair from Amazon.

.. code-block:: bash

    salt-cloud -f delete_keypair ec2 keyname=mykeypair

Launching instances into a VPC
==============================

Simple launching into a VPC
---------------------------

In the amazon web interface, identify the id of the subnet into which your
image should be created. Then, edit your cloud.profiles file like so:-

.. code-block:: yaml

    profile-id:
      provider: provider-name
      subnetid: subnet-XXXXXXXX
      image: ami-XXXXXXXX
      size: m1.medium
      ssh_username: ubuntu
      securitygroupid:
        - sg-XXXXXXXX

Specifying interface properties
-------------------------------

.. versionadded:: 2014.7.0

Launching into a VPC allows you to specify more complex configurations for
the network interfaces of your virtual machines, for example:-

.. code-block:: yaml

    profile-id:
      provider: provider-name
      image: ami-XXXXXXXX
      size: m1.medium
      ssh_username: ubuntu

      # Do not include either 'subnetid' or 'securitygroupid' here if you are
      # going to manually specify interface configuration
      #
      network_interfaces:
        - DeviceIndex: 0
          SubnetId: subnet-XXXXXXXX
          SecurityGroupId:
            - sg-XXXXXXXX
          
          # Uncomment this line if you would like to set an explicit private
          # IP address for the ec2 instance
          #
          # PrivateIpAddress: 192.168.1.66

          # Uncomment this to associate an existing Elastic IP Address with
          # this network interface:
          #
          # associate_eip: eni-XXXXXXXX

          # You can allocate more than one IP address to an interface. Use the
          # 'ip addr list' command to see them.
          #
          # SecondaryPrivateIpAddressCount: 2

          # Uncomment this to allocate a new Elastic IP Address to this
          # interface (will be associated with the primary private ip address
          # of the interface
          #
          # allocate_new_eip: True

          # Uncomment this instead to allocate a new Elastic IP Address to
          # both the primary private ip address and each of the secondary ones
          #
          allocate_new_eips: True

          # Uncomment this if you're creating NAT instances. Allows an instance
          # to accept IP packets with destinations other than itself.
          # SourceDestCheck: False

Note that it is an error to assign a 'subnetid' or 'securitygroupid' to a
profile where the interfaces are manually configured like this. These are both
really properties of each network interface, not of the machine itself.