

文件 AWS 開發套件範例 GitHub 儲存庫中有更多可用的 [AWS SDK 範例](https://github.com/awsdocs/aws-doc-sdk-examples)。

本文為英文版的機器翻譯版本，如內容有任何歧義或不一致之處，概以英文版為準。

# `DescribeTargetHealth` 搭配 AWS SDK 或 CLI 使用
<a name="elastic-load-balancing-v2_example_elastic-load-balancing-v2_DescribeTargetHealth_section"></a>

下列程式碼範例示範如何使用 `DescribeTargetHealth`。

動作範例是大型程式的程式碼摘錄，必須在內容中執行。您可以在下列程式碼範例的內容中看到此動作：
+  [建置及管理彈性服務](elastic-load-balancing-v2_example_cross_ResilientService_section.md) 

------
#### [ .NET ]

**適用於 .NET 的 SDK**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/dotnetv3/cross-service/ResilientService/ElasticLoadBalancerActions#code-examples)中設定和執行。

```
    /// <summary>
    /// Get the target health for a group by name.
    /// </summary>
    /// <param name="groupName">The name of the group.</param>
    /// <returns>The collection of health descriptions.</returns>
    public async Task<List<TargetHealthDescription>> CheckTargetHealthForGroup(string groupName)
    {
        List<TargetHealthDescription> result = null!;
        try
        {
            var groupResponse =
                await _amazonElasticLoadBalancingV2.DescribeTargetGroupsAsync(
                    new DescribeTargetGroupsRequest()
                    {
                        Names = new List<string>() { groupName }
                    });
            var healthResponse =
                await _amazonElasticLoadBalancingV2.DescribeTargetHealthAsync(
                    new DescribeTargetHealthRequest()
                    {
                        TargetGroupArn = groupResponse.TargetGroups[0].TargetGroupArn
                    });
            ;
            result = healthResponse.TargetHealthDescriptions;
        }
        catch (TargetGroupNotFoundException)
        {
            Console.WriteLine($"Target group {groupName} not found.");
        }
        return result;
    }
```
+  如需 API 詳細資訊，請參閱《適用於 .NET 的 AWS SDK API 參考》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/goto/DotNetSDKV3/elasticloadbalancingv2-2015-12-01/DescribeTargetHealth)。

------
#### [ CLI ]

**AWS CLI**  
**範例 1：描述目標群組的目標運作狀態**  
下列 `describe-target-health` 範例顯示指定目標群組的目標運作狀態詳細資訊。這些目標運作狀態良好。  

```
aws elbv2 describe-target-health \
    --target-group-arn arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/my-targets/73e2d6bc24d8a067
```
輸出：  

```
{
    "TargetHealthDescriptions": [
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "i-ceddcd4d",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "i-0f76fade",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        }
    ]
}
```
**範例 2：描述目標的運作狀態**  
下列 `describe-target-health` 範例顯示指定目標的運作狀態詳細資訊。此目標的運作狀態良好。  

```
aws elbv2 describe-target-health \
    --targets Id=i-0f76fade,Port=80 \
    --target-group-arn arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/my-targets/73e2d6bc24d8a067
```
輸出：  

```
{
    "TargetHealthDescriptions": [
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "i-0f76fade",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        }
    ]
}
```
下列範例輸出適用於在接聽程式動作中未指定之目標群組所屬的目標。此目標無法接收來自負載平衡器的流量。  

```
{
    "TargetHealthDescriptions": [
    {
        "HealthCheckPort": "80",
        "Target": {
            "Id": "i-0f76fade",
            "Port": 80
        },
            "TargetHealth": {
                "State": "unused",
                "Reason": "Target.NotInUse",
                "Description": "Target group is not configured to receive traffic from the load balancer"
            }
        }
    ]
}
```
下列範例輸出適用於在接聽程式動作中剛才指定之目標群組所屬的目標。目標仍在註冊中。  

```
{
    "TargetHealthDescriptions": [
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "i-0f76fade",
                "Port": 80
            },
            "TargetHealth": {
                "State": "initial",
                "Reason": "Elb.RegistrationInProgress",
                "Description": "Target registration is in progress"
            }
        }
    ]
}
```
以下範例輸出適用於運作狀態不佳的目標。  

```
{
    "TargetHealthDescriptions": [
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "i-0f76fade",
                "Port": 80
            },
            "TargetHealth": {
                "State": "unhealthy",
                "Reason": "Target.Timeout",
                "Description": "Connection to target timed out"
            }
        }
    ]
}
```
下列範例輸出適用於 Lambda 函式，且運作狀態檢查已停用的目標。  

```
{
    "TargetHealthDescriptions": [
        {
            "Target": {
                "Id": "arn:aws:lambda:us-west-2:123456789012:function:my-function",
                "AvailabilityZone": "all",
            },
            "TargetHealth": {
                "State": "unavailable",
                "Reason": "Target.HealthCheckDisabled",
                "Description": "Health checks are not enabled for this target"
            }
        }
    ]
}
```
+  如需 API 詳細資訊，請參閱《AWS CLI 命令參考》**中的 [DescribeTargetHealth](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/elbv2/describe-target-health.html)。

------
#### [ Java ]

**SDK for Java 2.x**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/usecases/resilient_service#code-examples)中設定和執行。

```
    // Checks the health of the instances in the target group.
    public List<TargetHealthDescription> checkTargetHealth(String targetGroupName) {
        DescribeTargetGroupsRequest targetGroupsRequest = DescribeTargetGroupsRequest.builder()
                .names(targetGroupName)
                .build();

        DescribeTargetGroupsResponse tgResponse = getLoadBalancerClient().describeTargetGroups(targetGroupsRequest);

        DescribeTargetHealthRequest healthRequest = DescribeTargetHealthRequest.builder()
                .targetGroupArn(tgResponse.targetGroups().get(0).targetGroupArn())
                .build();

        DescribeTargetHealthResponse healthResponse = getLoadBalancerClient().describeTargetHealth(healthRequest);
        return healthResponse.targetHealthDescriptions();
    }
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/goto/SdkForJavaV2/elasticloadbalancingv2-2015-12-01/DescribeTargetHealth)。

------
#### [ JavaScript ]

**適用於 JavaScript (v3) 的 SDK**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javascriptv3/example_code/cross-services/wkflw-resilient-service#code-examples)中設定和執行。

```
  const { TargetHealthDescriptions } = await client.send(
    new DescribeTargetHealthCommand({
      TargetGroupArn: TargetGroups[0].TargetGroupArn,
    }),
  );
```
+  如需 API 詳細資訊，請參閱《適用於 JavaScript 的 AWS SDK API 參考》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/client/elastic-load-balancing-v2/command/DescribeTargetHealthCommand)。

------
#### [ PowerShell ]

**Tools for PowerShell V4**  
**範例 1：此範例會傳回指定之目標群組中存在的目標運作狀態。**  

```
Get-ELB2TargetHealth -TargetGroupArn 'arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/test-tg/a4e04b3688be1970'
```
**輸出：**  

```
HealthCheckPort Target                                                TargetHealth
--------------- ------                                                ------------
80              Amazon.ElasticLoadBalancingV2.Model.TargetDescription Amazon.ElasticLoadBalancingV2.Model.TargetHealth
```
+  如需 API 詳細資訊，請參閱《AWS Tools for PowerShell Cmdlet 參考 (V4)》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/powershell/v4/reference)。

**Tools for PowerShell V5**  
**範例 1：此範例會傳回指定之目標群組中存在的目標運作狀態。**  

```
Get-ELB2TargetHealth -TargetGroupArn 'arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/test-tg/a4e04b3688be1970'
```
**輸出：**  

```
HealthCheckPort Target                                                TargetHealth
--------------- ------                                                ------------
80              Amazon.ElasticLoadBalancingV2.Model.TargetDescription Amazon.ElasticLoadBalancingV2.Model.TargetHealth
```
+  如需 API 詳細資訊，請參閱《AWS Tools for PowerShell Cmdlet 參考 (V5)》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/powershell/v5/reference)。

------
#### [ Python ]

**適用於 Python 的 SDK (Boto3)**  
 GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/elastic-load-balancing#code-examples)中設定和執行。

```
class ElasticLoadBalancerWrapper:
    """Encapsulates Elastic Load Balancing (ELB) actions."""

    def __init__(self, elb_client: boto3.client):
        """
        Initializes the LoadBalancer class with the necessary parameters.
        """
        self.elb_client = elb_client


    def check_target_health(self, target_group_name: str) -> List[Dict[str, Any]]:
        """
        Checks the health of the instances in the target group.

        :return: The health status of the target group.
        """
        try:
            tg_response = self.elb_client.describe_target_groups(
                Names=[target_group_name]
            )
            health_response = self.elb_client.describe_target_health(
                TargetGroupArn=tg_response["TargetGroups"][0]["TargetGroupArn"]
            )
        except ClientError as err:
            log.error(f"Couldn't check health of {target_group_name} target(s).")
            error_code = err.response["Error"]["Code"]
            if error_code == "LoadBalancerNotFoundException":
                log.error(
                    "Load balancer associated with the target group was not found. "
                    "Ensure the load balancer exists, is in the correct AWS region, and "
                    "that you have the necessary permissions to access it.",
                )
            elif error_code == "TargetGroupNotFoundException":
                log.error(
                    "Target group was not found. "
                    "Verify the target group name, check that it exists in the correct region, "
                    "and ensure it has not been deleted or created in a different account.",
                )
            log.error(f"Full error:\n\t{err}")
        else:
            return health_response["TargetHealthDescriptions"]
```
+  如需 API 詳細資訊，請參閱《AWS SDK for Python (Boto3) API 參考》**中的 [DescribeTargetHealth](https://docs.aws.amazon.com/goto/boto3/elasticloadbalancingv2-2015-12-01/DescribeTargetHealth)。

------