DescribeLoadBalancerTCPListenerAttribute - Server Load Balancer

Queries the configuration of a TCP listener.

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Test

RAM authorization

The table below describes the authorization required to call this API. You can define it in a Resource Access Management (RAM) policy. The table's columns are detailed below:

Action: The actions can be used in the Action element of RAM permission policy statements to grant permissions to perform the operation.
API: The API that you can call to perform the action.
Access level: The predefined level of access granted for each API. Valid values: create, list, get, update, and delete.
Resource type: The type of the resource that supports authorization to perform the action. It indicates if the action supports resource-level permission. The specified resource must be compatible with the action. Otherwise, the policy will be ineffective.
- For APIs with resource-level permissions, required resource types are marked with an asterisk (*). Specify the corresponding Alibaba Cloud Resource Name (ARN) in the Resource element of the policy.
- For APIs without resource-level permissions, it is shown as All Resources. Use an asterisk (*) in the Resource element of the policy.
Condition key: The condition keys defined by the service. The key allows for granular control, applying to either actions alone or actions associated with specific resources. In addition to service-specific condition keys, Alibaba Cloud provides a set of common condition keys applicable across all RAM-supported services.
Dependent action: The dependent actions required to run the action. To complete the action, the RAM user or the RAM role must have the permissions to perform all dependent actions.

Action

Access level

Resource type

Condition key

Dependent action

slb:DescribeLoadBalancerTCPListenerAttribute

get

*loadbalancer

acs:slb:{#regionId}:{#accountId}:loadbalancer/{#loadbalancerId}

slb:tag
slb:tag
slb:tag
slb:tag
slb:tag

None

Request parameters

Parameter	Type	Required	Description	Example
RegionId	string	No	The region ID of the Classic Load Balancer instance. You can find the region ID in the Regions and zones list or by calling the DescribeRegions operation.	cn-hangzhou
LoadBalancerId	string	Yes	The ID of the Classic Load Balancer instance.	lb-bp1ygod3yctvg1y****
ListenerPort	integer	Yes	The frontend port used by the Classic Load Balancer instance. Valid values: 1 to 65535.	80

Response elements

Element	Type	Description	Example
	object
VServerGroupId	string	The ID of the attached vServer group.	rsp-cige6******8
Status	string	The current status of the listener. Valid values: running: The listener is running normally. stopped: The listener is stopped.	stopped
AclType	string	The access control type. Valid values: white: Only requests from IP addresses or CIDR blocks in the specified access control policy group are forwarded. Use this option when your application allows only specific IP addresses to access it. Enabling a whitelist carries business risks. After you enable a whitelist, only IP addresses in the whitelist can access the listener. If you enable a whitelist but do not add any IP addresses to the access control policy group, the listener forwards all requests. black: Requests from IP addresses or CIDR blocks in the specified access control policy group are blocked. Use this option when your application restricts access from specific IP addresses. If you enable a blacklist but do not add any IP addresses to the access control policy group, the listener forwards all requests. Note This parameter is required if the AclStatus parameter is set to on.	white
ConnectionDrainTimeout	integer	The timeout period for connection draining. This parameter is returned only if the ConnectionDrain parameter is set to on. Valid values: 10 to 900 seconds.	300
RequestId	string	The request ID.	365F4154-92F6-4AE4-92F8-7FF34B540710
HealthCheckConnectPort	integer	The port used for health checks. Valid values: 1 to 65535. If you do not specify this parameter, the backend server port (BackendServerPort) is used.	8080
Description	string	The custom name of the listener.	TCP_80
Bandwidth	integer	The peak bandwidth of the listener, in Mbit/s. Valid values: -1: For Internet-facing SLB instances that use pay-by-data-transfer billing, you can set the peak bandwidth to -1 to remove the bandwidth limit. 1 to 5120: For Internet-facing SLB instances that use pay-by-bandwidth billing, you can set the peak bandwidth for each listener. However, the sum of the peak bandwidths of all listeners cannot exceed the peak bandwidth of the instance.	-1
HealthCheckType	string	The health check method for the TCP listener. Valid values: tcp or http.	tcp
MasterSlaveServerGroupId	string	The ID of the attached primary/secondary server group.	rsp-0bfucw****
BackendServerPort	integer	The backend port used by the Classic Load Balancer instance. Note This parameter is not displayed if the backend server group is a vServer group.	443
AclStatus	string	Whether to enable access control. Valid values: on: Enable access control. off: Disable access control.	off
HealthCheckDomain	string	The domain name used for health checks. Valid values: $_ip: The private IP address of the backend server. If you specify an IP address or omit this parameter, Server Load Balancer uses the private IP address of each backend server as the domain name for health checks. domain: A domain name that is 1 to 80 characters in length and contains only letters, digits, periods (.), and hyphens (-).	www.domain.com
UnhealthyThreshold	integer	The unhealthy threshold. After consecutive health check failures reach this value, the health check status of a backend server changes from success to failure. Valid values: 2 to 10.	4
HealthCheckHttpCode	string	The HTTP status code that indicates a successful health check.	http_2xx
ProxyProtocolV2Enabled	boolean	Whether to enable Proxy Protocol V2 to pass client source IP addresses to backend servers. Valid values: true: Enable. false: Disable.	false
PersistenceTimeout	integer	The timeout period for session persistence. Valid values: 0 to 3600 seconds. Default value: 0, which disables session persistence.	0
ListenerPort	integer	The frontend port used by the Classic Load Balancer instance.	110
HealthCheckInterval	integer	The interval between health checks. Valid values: 1 to 50 seconds.	5
HealthCheckURI	string	The URL used for health checks. The URL must be 1 to 80 characters in length and can contain only letters, digits, hyphens (-), forward slashes (/), periods (.), percent signs (%), question marks (?), number signs (#), and ampersands (&). The URL cannot be just a forward slash (/), but it must start with a forward slash (/).	/test/index.html
AclId	string	The ID of the access control policy group attached to the listener. This parameter is required if the AclStatus parameter is set to on.	acl-uf60jwfi******
SynProxy	string	Whether to enable SynProxy attack prevention for the load balancer. We recommend that you do not change this parameter. Let Server Load Balancer manage it. enable: Enable SynProxy. disable: Disable SynProxy.	disable
Scheduler	string	The scheduling algorithm. Valid values: wrr (default): Backend servers with higher weights receive more requests. rr: Requests are distributed to backend servers in sequence. sch: Consistent hashing based on source IP addresses. Requests from the same source IP address are routed to the same backend server. tch: Consistent hashing based on four-tuples (source IP address, destination IP address, source port, and destination port). Requests in the same flow are routed to the same backend server. Note The sch and tch algorithms are supported only by guaranteed-performance instances.	wrr
EstablishedTimeout	integer	The connection timeout period.	500
HealthCheckConnectTimeout	integer	The timeout period for health checks.	100
HealthyThreshold	integer	The healthy threshold. After consecutive health check successes reach this value, the health check status of a backend server changes from failure to success. Valid values: 2 to 10.	4
ConnectionDrain	string	Whether to enable connection draining. This parameter is returned only if the ConnectionDrain parameter is set to on. Valid values: on: Enable connection draining. off: Disable connection draining.	off
HealthCheckMethod	string	The health check method.	tcp
HealthCheck	string	Whether to enable health checks. Valid values: on: Enable health checks. off: Disable health checks.	on
AclIds	object
AclId	array	A list of access control policy group IDs.

LoadBalancerId	string	The ID of the Classic Load Balancer instance.	lb-bp1ygod3yctvg1y****
Tags	object
Tag	array<object>	A list of tags.
	object	A list of tags.
TagKey	string	The tag key of the listener. Valid values of N: 1 to 20. If you specify this parameter, it cannot be an empty string. It can be up to 128 characters in length. It cannot start with `aliyun` or `acs:`. It cannot contain `http://` or `https://`.	TestKey
TagValue	string	The tag value of the listener. Valid values of N: 1 to 20. If you specify this parameter, it can be an empty string. It can be up to 128 characters in length. It cannot start with `acs:`. It cannot contain `http://` or `https://`.	TestValue

Examples

Success response

JSON format

{
  "VServerGroupId": "rsp-cige6******8",
  "Status": "stopped",
  "AclType": "white",
  "ConnectionDrainTimeout": 300,
  "RequestId": "365F4154-92F6-4AE4-92F8-7FF34B540710",
  "HealthCheckConnectPort": 8080,
  "Description": "TCP_80",
  "Bandwidth": -1,
  "HealthCheckType": "tcp",
  "MasterSlaveServerGroupId": "rsp-0bfucw****",
  "BackendServerPort": 443,
  "AclStatus": "off",
  "HealthCheckDomain": "www.domain.com",
  "UnhealthyThreshold": 4,
  "HealthCheckHttpCode": "http_2xx",
  "ProxyProtocolV2Enabled": false,
  "PersistenceTimeout": 0,
  "ListenerPort": 110,
  "HealthCheckInterval": 5,
  "HealthCheckURI": "/test/index.html",
  "AclId": "acl-uf60jwfi******",
  "SynProxy": "disable",
  "Scheduler": "wrr",
  "EstablishedTimeout": 500,
  "HealthCheckConnectTimeout": 100,
  "HealthyThreshold": 4,
  "ConnectionDrain": "off",
  "HealthCheckMethod": "tcp",
  "HealthCheck": "on",
  "AclIds": {
    "AclId": [
      ""
    ]
  },
  "LoadBalancerId": "lb-bp1ygod3yctvg1y****",
  "Tags": {
    "Tag": [
      {
        "TagKey": "TestKey",
        "TagValue": "TestValue"
      }
    ]
  }
}

Error codes

HTTP status code	Error code	Error message	Description
400	LocationServiceTimeout	Location service connection timeout. Please try again later.
403	UnauthorizedRegion	The specified region of is not authorized.	The specified region of is not authorized.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.