RunInstances

Amazon Elastic Compute Cloud: 2007-08-29

previous page next page

RunInstances

The RunInstances operation launches a specified number of instances.

[Note] Note

The Query version of RunInstances only allows instances of a single AMI to be launched in one call. This is different from the SOAP API version of the call, but similar to the ec2-run-instances command line tool.

If Amazon EC2 cannot launch the minimum number AMIs you request, no instances launch. If there is insufficient capacity to launch the maximum number of AMIs you request, Amazon EC2 launches as many as possible to satisfy the requested maximum values.

Every instance is launched in a security group. If you do not specify a security group at launch, the instances start in your default security group.

An optional instance type can be specified. For information about instance types, see Selecting Instance Types.

You can provide an optional key pair ID for each image in the launch request. All instances that are created from images that use this key pair will have access to the associated public key at boot. You can use this key to provide secure access to an instance of an image on a per-instance basis. Amazon EC2 public images use this feature to provide secure access without passwords.

[Important] Important

Launching public images without a key pair ID will leave them inaccessible.

The public key material is made available to the instance at boot time by placing it in the openssh_id.pub file on a logical device that is exposed to the instance as /dev/sda2 (the ephemeral store). The format of this file is suitable for use as an entry within ~/.ssh/authorized_keys (the OpenSSH format). This can be done at boot (e.g., as part of rc.local) allowing for secure access without passwords.

Optional user data can be provided in the launch request. All instances comprising the launch request have access to this data (see Instance Metadata for details).

[Note] Note

If any of the AMIs have a product code attached for which the user has not subscribed, the RunInstances call will fail.

Request Parameters

The following table describes the request parameters for RunInstances. Parameter names are case sensitive.

Name Description Required

ImageId

ID of the AMI with which to launch instances.

Type: String

Yes

MinCount

Minimum number of instances to launch.

Type: Int

Yes

MaxCount

Maximum number of instances to launch.

Type: Int

Yes

KeyName

Name of the key pair with which to launch instances.

Type: String

No

SecurityGroup.n

Names of the security groups with which to associate the instances.

Type: String

No

UserData

The user data available to the launched instances. This should be Base64 encoded. For more information on encoding details, see UserDataType.

Type: String

No

AddressingType

The addressing scheme with which to launch the instance. The supported addressing type is public. For the public scheme, the instance has a private and public IP address that are mapped through NAT. For more information, see Instance Addressing.

[Note]Note

To support our legacy cluster, early beta customers can also specify direct. In the direct scheme, the instance has a single public IP address.

Type: String

No

InstanceType

This specifies the instance type.

Options include m1.small, m1.large, and m1.xlarge.

The default value is m1.small.

For more information on instance types, see Selecting Instance Types

Type: xsd:string

No

Response Elements

The following table describes the default response tags included in RunInstances responses.

Name Description

RunInstancesResponse

Status information about the instances launched.

Type: ec2ReservationInfoType

Sample Request 

https://ec2.amazonaws.com/
?Action=RunInstances
&ImageId=ami-60a54009
&MaxCount=3
&MinCount=1
&AddressingType=public
&...auth parameters...

Sample Response 

<RunInstancesResponse xmlns="http://ec2.amazonaws.com/doc/2007-08-29">
  <reservationId>r-47a5402e</reservationId>
  <ownerId>495219933132</ownerId>
  <groupSet>
    <item>
      <groupId>default</groupId>
    </item>
  </groupSet>
  <instancesSet>
    <item>
      <instanceId>i-2ba64342</instanceId>
      <imageId>ami-60a54009</imageId>
      <instanceState>
        <code>0</code>
	<name>pending</name>
      </instanceState>
      <privateDnsName></privateDnsName>
      <dnsName></dnsName>
      <keyName>example-key-name</keyName>
       <amiLaunchIndex>0</amiLaunchIndex>
      <InstanceType>m1.small</InstanceType>
      <launchTime>2007-08-07T11:51:50.000Z</launchTime>
    </item>
    <item>
      <instanceId>i-2bc64242</instanceId>
      <imageId>ami-60a54009</imageId>
      <instanceState>
        <code>0</code>
	<name>pending</name>
      </instanceState>
      <privateDnsName></privateDnsName>
      <dnsName></dnsName>
      <keyName>example-key-name</keyName>
      <amiLaunchIndex>1</amiLaunchIndex>
      <InstanceType>m1.small</InstanceType>
      <launchTime>2007-08-07T11:51:50.000Z</launchTime>
    </item>
    <item>
      <instanceId>i-2be64332</instanceId>
      <imageId>ami-60a54009</imageId>
      <instanceState>
        <code>0</code>
	<name>pending</name>
      </instanceState>
      <privateDnsName></privateDnsName>
      <dnsName></dnsName>
      <keyName>example-key-name</keyName>
      <amiLaunchIndex>2</amiLaunchIndex>
      <InstanceType>m1.small</InstanceType>
      <launchTime>2007-08-07T11:51:50.000Z</launchTime>     
    </item>
  </instancesSet>
</RunInstancesResponse>

Related Operations

previous page start next page