DescribeRules - Server Load Balancer - Alibaba Cloud Documentation Center

Queries the forwarding rules that are configured for a specified listener.

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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
slb:DescribeRules	get	loadbalancer acs:slb:{#regionId}:{#accountId}:loadbalancer/{#loadbalancerId}	slb:tag	none

Request parameters

Parameter	Type	Required	Description	Example
RegionId	string	Yes	The ID of the region where the SLB instance is deployed. You can call the DescribeRegions operation to query the most recent region list.	cn-hangzhou
LoadBalancerId	string	Yes	The ID of the SLB instance.	lb-bp1ca0zt07t934****
ListenerProtocol	string	No	The frontend listener protocol that is used by the SLB instance. Note This parameter is required when listeners that use different protocols listen on the same port.	https
ListenerPort	integer	Yes	The frontend listener port that is used by the Server Load Balancer (SLB) instance. Valid values: 1 to 65535.	90

Response parameters

Parameter	Type	Description	Example
	object
RequestId	string	The ID of the request.	9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C
Rules	array<object>	The forwarding rules.
Rule	object
HealthCheckHttpCode	string	The HTTP status code that indicates a successful health check. Multiple HTTP status codes are separated by commas (,). Default value: http_2xx. Valid values: http_2xx, http_3xx, http_4xx, and http_5xx. Note If you set the HealthCheck parameter to on, this parameter is required.	http_3xx
VServerGroupId	string	The ID of the destination vServer group specified in the forwarding rule.	rsp-6cejjzl****
Domain	string	The requested domain name specified in the forwarding rule.	test.com
Cookie	string	The cookie that is configured on the backend server. The value must be 1 to 200 characters in length, and can contain only ASCII letters and digits. It cannot contain commas (,), semicolons (;), or spaces. It cannot start with a dollar sign ($). Note If you set the StickySession parameter to on and the StickySessionType parameter to server, this parameter is required.	23
HealthCheckInterval	integer	The time interval between two consecutive health checks. Valid values: 1 to 50. Unit: seconds. Note If you set the HealthCheck parameter to on, this parameter is required.	5
Url	string	The requested path specified in the forwarding rule.	/cache
HealthCheckURI	string	The URI that is used for health checks. Note If you set the HealthCheck parameter to on, this parameter is required.	/example
StickySessionType	string	The method that is used to handle a cookie. Valid values: insert: inserts a cookie into the response. SLB inserts a cookie (SERVERID) into the first HTTP or HTTPS response packet that is sent to a client. The next request from the client will contain this cookie, and the listener will distribute this request to the recorded backend server. server: rewrites a cookie. When SLB detects a user-defined cookie, SLB overwrites the original cookie with the user-defined cookie. The next request from the client contains the user-defined cookie, and the listener distributes the request to the recorded backend server. Note If you set the StickySession parameter to on, this parameter is required.	insert
RuleName	string	The name of the forwarding rule. The name must be 1 to 80 characters in length, and can contain only letters, digits, hyphens (-), forward slashes (/), periods (.),and underscores (_). Note The name of each forwarding rule must be unique within a listener.	Rule2
RuleId	string	The ID of the forwarding rule.	rule-tybqi6****
HealthCheckConnectPort	integer	The backend port that is used for health checks. Valid values: 1 to 65535. Note If you set the HealthCheck parameter to on, this parameter is required. If this parameter is empty but HealthCheck is set to on, the listener port is used for health checks.	45
Scheduler	string	The scheduling algorithm. Valid values: wrr (default): Backend servers that have higher weights receive more requests than backend servers that have lower weights. rr: Requests are distributed to backend servers in sequence. Note If you set the ListenerSync parameter to off, this parameter is required. If you set the parameter to on, the configuration of the listener is used.	wrr
HealthCheckTimeout	integer	The timeout period of a health check response. If a backend ECS instance does not respond within the specified timeout period, the ECS instance fails the health check. Unit: seconds Valid values: 1 to 300. Note When you set the HealthCheck parameter to on, this parameter takes effect.	34
ListenerSync	string	Indicates whether the forwarding rule uses the scheduling algorithm, session persistence, and health check configurations of the listener. Valid values: on and off. off: does not use the configurations of the listener. You can customize health check and session persistence configurations for the forwarding rule. on: uses the configurations of the listener.	off
HealthyThreshold	integer	Specifies the number of successful health checks that must be consecutively performed before a backend server can be declared healthy (from fail to success). Valid values: 2 to 10. Note If you set the HealthCheck parameter to on, this parameter is required.	5
CookieTimeout	integer	The timeout period of a cookie. Valid values: 1 to 86400. Unit: seconds. Note If you set the StickySession parameter to on and the StickySessionType parameter to insert, this parameter is required.	56
HealthCheckDomain	string	The domain name that is used for health checks. Valid values: $_ip: The private IP address of the backend server. If you do not set this parameter or set the parameter to $_ip, the SLB instance uses the private IP address of each backend server as the domain name for health checks. domain: The domain name must be 1 to 80 characters in length. The domain name can contain only letters, digits, periods (.),and hyphens (-). Note If you set the HealthCheck parameter to on, this parameter is required.	www.domain.com
UnhealthyThreshold	integer	Specifies the number of times that a healthy backend server must consecutively fail health checks before it is declared unhealthy (from success to fail). Valid values: 2 to 10 Note If you set the HealthCheck parameter to on, this parameter is required.	2
StickySession	string	Specifies whether to enable session persistence. Valid values: on and off. Note If you set the ListenerSync parameter to off, this parameter is required. If you set the parameter to on, the configuration of the listener is used.	off
HealthCheck	string	Indicates whether health checks are enabled. Valid values: on and off. Note If you set the ListenerSync parameter to off, this parameter is required. If you set the parameter to on, the configuration of the listener is used.	off

Examples

Sample success responses

JSONformat

{
  "RequestId": "9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C",
  "Rules": {
    "Rule": [
      {
        "HealthCheckHttpCode": "http_3xx",
        "VServerGroupId": "rsp-6cejjzl****",
        "Domain": "test.com",
        "Cookie": "23",
        "HealthCheckInterval": 5,
        "Url": "/cache",
        "HealthCheckURI": "/example",
        "StickySessionType": "insert",
        "RuleName": "Rule2",
        "RuleId": "rule-tybqi6****",
        "HealthCheckConnectPort": 45,
        "Scheduler": "wrr",
        "HealthCheckTimeout": 34,
        "ListenerSync": "off",
        "HealthyThreshold": 5,
        "CookieTimeout": 56,
        "HealthCheckDomain": "www.domain.com",
        "UnhealthyThreshold": 2,
        "StickySession": "off",
        "HealthCheck": "off"
      }
    ]
  }
}

Error codes

HTTP status code	Error code	Error message
400	TooManyListeners	More than 1 listener is found, please be more specified.

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