DescribeLoadBalancerHTTPListenerAttribute - ENS - Alibaba Cloud Documentation Center

Queries the configuration of an HTTP listener.

Operation description

You can call this operation up to 100 times per second per account.
You can call this operation up to 10 times per second per user.

Debugging

You can run this interface directly in OpenAPI Explorer, saving you the trouble of calculating signatures. After running successfully, OpenAPI Explorer can automatically generate SDK code samples.

Debug

Authorization information

The following table shows the authorization information corresponding to the API. The authorization information can be used in the Action policy element to grant a RAM user or RAM role the permissions to call this API operation. Description:

Operation: the value that you can use in the Action element to specify the operation on a resource.
Access level: the access level of each operation. The levels are read, write, and list.
Resource type: the type of the resource on which you can authorize the RAM user or the RAM role to perform the operation. Take note of the following items:
- The required resource types are displayed in bold characters.
- If the permissions cannot be granted at the resource level, All Resources is used in the Resource type column of the operation.
Condition Key: the condition key that is defined by the cloud service.
Associated operation: other operations that the RAM user or the RAM role must have permissions to perform to complete the operation. To complete the operation, the RAM user or the RAM role must have the permissions to perform the associated operations.

Operation	Access level	Resource type	Condition key	Associated operation
ens:DescribeLoadBalancerHTTPListenerAttribute	get	All Resources ``	none	none

Request parameters

Parameter	Type	Required	Description	Example
ListenerPort	integer	Yes	The listener port that you want to query. Valid values: 1 to 65535.	8080
LoadBalancerId	string	Yes	The ID of the ELB instance.	lb-5snthcyu1x10g7tywj7iu****

Response parameters

Parameter	Type	Description	Example
	object	Schema of Response
RequestId	string	The ID of the request.	473469C7-AA6F-4DC5-B3DB-A3DC0DE3C83E
ListenerPort	integer	The listener port.	80
Status	string	The status of the listener. Valid values: Running Stopped Starting Configuring Stopping	Running
Bandwidth	integer	The peak bandwidth of the Edge Load Balancer (ELB) instance. The default value is -1, which indicates that the bandwidth is not limited.	-1
Scheduler	string	The routing algorithm. Valid values: wrr: Backend servers with higher weights receive more requests than those with lower weights. wlc: Requests are distributed based on the weight and load of each backend server. The load refers to the number of connections to a backend server. If two backend servers have the same weight, the backend server that has fewer connections receives more requests. rr: Requests are distributed to backend servers in sequence. sch: consistent hashing that is based on source IP addresses. Requests from the same source IP address are distributed to the same backend server. qch: consistent hashing that is based on QUIC connection IDs. Requests that contain the same QUIC connection ID are distributed to the same backend server. iqch: consistent hashing that is based on specific three bytes of the iQUIC CIDs. Requests whose second to fourth bytes are the same are distributed to the same backend server.	wrr
HealthCheck	string	Indicates whether the health check feature is enabled. Valid values: on off	on
HealthyThreshold	integer	The number of consecutive successful health checks that must occur before an unhealthy and inaccessible backend server is declared healthy and accessible. Valid values: 2 to 10. Note This parameter is returned only if you set HealthCheck to on.	3
UnhealthyThreshold	integer	The number of consecutive failed health checks that must occur before a healthy and accessible backend server is declared unhealthy and inaccessible. Valid values: 2 to 10. Note This parameter is returned only if you set HealthCheck to on.	3
HealthCheckTimeout	integer	The timeout period of a health check response. If a backend server does not respond within the specified timeout period, the server fails the health check. Default value: 5. Valid values: 1 to 300. Unit: seconds. Note This parameter takes effect only if the HealthCheck parameter is set to on. If the value of HealthCheckTimeout is smaller than the value of HealthCheckInterval, the timeout period specified by HealthCheckTimeout becomes invalid, and the value of HealthCheckInterval is used as the timeout period.	10
HealthCheckConnectPort	integer	The port that is used for health checks. Valid values: 1 to 65535. If you leave this parameter empty, the port specified by BackendServerPort is used for health checks. Note This parameter is returned only if you set HealthCheck to on.	5000
HealthCheckInterval	integer	The interval at which health checks are performed. Valid values: 1 to 50. Unit: seconds. Note This parameter is returned only if you set HealthCheck to on.	5
Description	string	The description of the listener. The description must be 1 to 80 characters in length. Note The value cannot start with `http://` or `https://`.	abc
ListenerForward	string	Indicates whether HTTP-to-HTTPS redirection is enabled. Valid values: on: HTTP-to-HTTPS redirection is enabled. off (default)	off
ForwardPort	integer	The listener port that is used to redirect HTTP requests to HTTPS.	10002
RequestTimeout	integer	The timeout period of requests. Default value: 60. Valid values: 1 to 180. Unit: seconds. Note If no response is received from the backend server within the specified timeout period, ELB returns an HTTP 504 error code to the client.	60
IdleTimeout	integer	The timeout period for idle connections. Default value: 15. Valid values: 1 to 60. Unit: seconds. Note If no request is received within the specified timeout period, ELB closes the connection. When another request is received, ELB establishes a new connection.	15
HealthCheckHttpCode	string	The HTTP status codes for a successful health check. Valid values: http_2xx (default) http_3xx. http_4xx http_5xx Note This parameter is returned only if you set HealthCheck to on.	http_2xx
HealthCheckDomain	string	The domain name that is used for health checks. Note This parameter is returned only if you set HealthCheck to on.	www.example.com
HealthCheckURI	string	The URI used for health checks. The URI must be 1 to 80 characters in length. Note A URL must start with a forward slash (`/`) but cannot contain only forward slashes (`/`). This parameter takes effect only if the HealthCheck parameter is set to on.	/checkpreload.htm
ServerCertificateId	string	The ID of the server certificate.	6027667
HealthCheckMethod	string	The health check method used in HTTP health checks. Valid values: head: requests the head of the page. get: requests the specified part of the page and returns the entity body. Note This parameter is returned only if you set HealthCheck to on.	head
XForwardedFor	string	Indicates whether the X-Forwarded-For header is used to obtain the real IP address of the client. Valid values: on (default) off	on
BackendServerPort	integer	The backend port that is used by the ELB instance. Valid values: 1 to 65535.	8080

Examples

Sample success responses

JSONformat

{
  "RequestId": "473469C7-AA6F-4DC5-B3DB-A3DC0DE3C83E",
  "ListenerPort": 80,
  "Status": "Running",
  "Bandwidth": -1,
  "Scheduler": "wrr",
  "HealthCheck": "on",
  "HealthyThreshold": 3,
  "UnhealthyThreshold": 3,
  "HealthCheckTimeout": 10,
  "HealthCheckConnectPort": 5000,
  "HealthCheckInterval": 5,
  "Description": "abc",
  "ListenerForward": "off",
  "ForwardPort": 10002,
  "RequestTimeout": 60,
  "IdleTimeout": 15,
  "HealthCheckHttpCode": "http_2xx",
  "HealthCheckDomain": "www.example.com",
  "HealthCheckURI": "/checkpreload.htm",
  "ServerCertificateId": "6027667",
  "HealthCheckMethod": "head",
  "XForwardedFor": "on\n",
  "BackendServerPort": 8080
}

Error codes

HTTP status code	Error code	Error message	Description
400	LoadBalancerNotFound	The input parameter loadBalancerId that is not found.	The load balancing instance does not exist.
400	ListenerNotFound	Listener is not found.	Listener does not exist
400	ens.interface.error	Failed to call API.	-
400	NoPermission	Permission denied.	-
400	InvalidParameter.%s	The specified field %s invalid. Please check it again.	-

For a list of error codes, visit the Service error codes.

Change history

Change time	Summary of changes	Operation
2024-08-08	The Error code has changed. The response structure of the API has changed	View Change Details
2024-07-04	The Error code has changed	View Change Details
2024-06-04	The Error code has changed. The response structure of the API has changed	View Change Details