# Instance
<a name="API_Instance"></a>

Describes an EC2 instance.

## Contents
<a name="API_Instance_Contents"></a>

 ** AvailabilityZone **   
The Availability Zone in which the instance is running.  
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

 ** HealthStatus **   
The last reported health status of the instance. `Healthy` means that the instance is healthy and should remain in service. `Unhealthy` means that the instance is unhealthy and that Amazon EC2 Auto Scaling should terminate and replace it.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 32.  
Pattern: `[\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*`   
Required: Yes

 ** InstanceId **   
The ID of the instance.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 19.  
Pattern: `[\u0020-\uD7FF\uE000-\uFFFD\uD800\uDC00-\uDBFF\uDFFF\r\n\t]*`   
Required: Yes

 ** LifecycleState **   
A description of the current lifecycle state. The `Quarantined` state is not used. For more information, see [Amazon EC2 Auto Scaling instance lifecycle](https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-lifecycle.html) in the *Amazon EC2 Auto Scaling User Guide*.   
Type: String  
Valid Values: `Pending | Pending:Wait | Pending:Proceed | Quarantined | InService | Terminating | Terminating:Wait | Terminating:Proceed | Terminating:Retained | Terminated | Detaching | Detached | EnteringStandby | Standby | ReplacingRootVolume | ReplacingRootVolume:Wait | ReplacingRootVolume:Proceed | RootVolumeReplaced | Warmed:Pending | Warmed:Pending:Wait | Warmed:Pending:Proceed | Warmed:Pending:Retained | Warmed:Terminating | Warmed:Terminating:Wait | Warmed:Terminating:Proceed | Warmed:Terminating:Retained | Warmed:Terminated | Warmed:Stopped | Warmed:Running | Warmed:Hibernated`   
Required: Yes

 ** ProtectedFromScaleIn **   
Indicates whether the instance is protected from termination by Amazon EC2 Auto Scaling when scaling in.  
Type: Boolean  
Required: Yes

 ** AvailabilityZoneId **   
 The Availability Zone ID where the instance was launched.   
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: No

 ** ImageId **   
 The ID of the Amazon Machine Image (AMI) used for the instance's current root volume. This value reflects the most recent AMI applied to the instance, including updates made through root volume replacement operations.   
 This field appears for:   
+ Instances with root volume replacements through Instance Refresh
+ Instances launched with AMI overrides 
This field won't appear for:  
+ Existing instances launched from Launch Templates without overrides
+ Existing instances that didn’t have their root volume replaced through Instance Refresh
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: No

 ** InstanceType **   
The instance type of the EC2 instance.  
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: No

 ** LaunchConfigurationName **   
The launch configuration associated with the instance.  
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: No

 ** LaunchTemplate **   
The launch template for the instance.  
Type: [LaunchTemplateSpecification](API_LaunchTemplateSpecification.md) object  
Required: No

 ** WeightedCapacity **   
The number of capacity units contributed by the instance based on its instance type.  
Valid Range: Minimum value of 1. Maximum value of 999.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 3.  
Pattern: `^[\u0031-\u0039][\u0030-\u0039]{0,2}$`   
Required: No

## See Also
<a name="API_Instance_SeeAlso"></a>

For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/autoscaling-2011-01-01/Instance) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/autoscaling-2011-01-01/Instance) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/autoscaling-2011-01-01/Instance)