Request Parameters Errors Examples See Also

AttachInstances

Attaches one or more EC2 instances to the specified Auto Scaling group.

When you attach instances, Amazon EC2 Auto Scaling increases the desired capacity of the group by the number of instances being attached. If the number of instances being attached plus the desired capacity of the group exceeds the maximum size of the group, the operation fails.

If there is a Classic Load Balancer attached to your Auto Scaling group, the instances are also registered with the load balancer. If there are target groups attached to your Auto Scaling group, the instances are also registered with the target groups.

For more information, see Detach or attach instances in the Amazon EC2 Auto Scaling User Guide.

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

AutoScalingGroupName

The name of the Auto Scaling group.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 255.

Pattern: [\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*

Required: Yes

InstanceIds.member.N

The IDs of the instances. You can specify up to 20 instances.

Type: Array of strings

Length Constraints: Minimum length of 1. Maximum length of 19.

Pattern: [\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*

Required: No

Errors

For information about the errors that are common to all actions, see Common Errors.

ResourceContention

You already have a pending update to an Amazon EC2 Auto Scaling resource (for example, an Auto Scaling group, instance, or load balancer).

HTTP Status Code: 500

ServiceLinkedRoleFailure

The service-linked role is not yet ready for use.

HTTP Status Code: 500

Examples

Example

This example illustrates one usage of AttachInstances.

Sample Request


https://autoscaling.amazonaws.com/?Action=AttachInstances
&AutoScalingGroupName=my-asg
&InstanceIds.member.1=i-1234567890abcdef0
&Version=2011-01-01
&AUTHPARAMS