UpdateServerGroupAttribute - Server Load Balancer - Alibaba Cloud Documentation Center

Modifies the configurations of a server group, such as health checks, session persistence, the server group name, the routing algorithm, and the protocol.

Operation description

Description

UpdateServerGroupAttribute is an asynchronous operation. After a request is sent, the system returns a request ID and runs the task in the background. You can call the ListServerGroups operation to query the status of a server group:

If a server group is in the Configuring state, the configuration of the server group is being modified.
If a server group is in the Available state, the configuration of the server group is modified.

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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

alb:UpdateServerGroupAttribute

update

*ServerGroup

acs:alb:{#regionId}:{#accountId}:servergroup/{#servergroupId}

None

Request parameters

Parameter	Type	Required	Description	Example
ServerGroupName	string	No	The server group name. The name must be 2 to 128 characters in length and can contain letters, digits, periods (.), underscores (_), and hyphens (-). The name must start with a letter.	test
Scheduler	string	No	The scheduling algorithm. Valid values: Wrr: the weighted round robin algorithm. Backend servers that have higher weights receive more requests than those that have lower weights. Wlc: the weighted least connections algorithm. Requests are distributed based on the weights and the number of connections to backend servers. If two backend servers have the same weight, the backend server that has fewer connections is expected to receive more requests. Sch: the consistent hashing algorithm. Requests from the same source IP address are distributed to the same backend server.	Wrr
ClientToken	string	No	The client token that is used to ensure the idempotence of the request. You can use the client to generate the token, but you must make sure that the token is unique among different requests. The token can contain only ASCII characters. Note If you do not specify this parameter, the system automatically uses the request ID as the client token. The request ID may be different for each request.	5A2CFF0E-5718-45B5-9D4D-70B3******
DryRun	boolean	No	Specifies whether to perform only a dry run, without performing the actual request. Valid values: true: checks the request without performing the operation. The system checks the request for potential issues, including missing parameter values, incorrect request syntax, and service limits. If the request fails the dry run, an error code is returned. If the request passes the dry run, the `DryRunOperation` error code is returned. false (default): performs a dry run and performs the actual request. If the request passes the dry run, a `2xx` HTTP status code is returned and the operation is performed.	true
HealthCheckConfig	object	No	The configuration of health checks.
HealthCheckConnectPort	integer	No	The backend port that is used for health checks. Valid values: 0 to 65535. If you set the value to 0, the backend port is used for health checks. Note This parameter takes effect only if you set HealthCheckEnabled to true.	80
HealthCheckEnabled	boolean	No	Specifies whether to enable the health check feature. Valid values: true false	true
HealthCheckHost	string	No	The domain name that is used for health checks. Backend Server Internal IP (default): Use the internal IP address of backend servers as the health check domain name. Custom Domain Name: Enter a domain name. The domain name must be 1 to 80 characters in length. The domain name can contain lowercase letters, digits, hyphens (-), and periods (.). The domain name must contain at least one period (.) but cannot start or end with a period (.). The rightmost domain label of the domain name can contain only letters, and cannot contain digits or hyphens (-). The domain name cannot start or end with a hyphen (-). Note This parameter takes effect only if HealthCheckProtocol is set to HTTP, HTTPS, or gRPC.	example.com
HealthCheckCodes	array	No	The HTTP status codes that indicate healthy backend servers.
	string	No	The HTTP status codes that indicate healthy backend servers. When HealthCheckProtocol is set to HTTP or HTTPS, you can set HealthCheckCodes to http_2xx (default value), http_3xx, http_4xx, and http_5xx. Separate multiple HTTP status codes with commas (,). When HealthCheckProtocol is set to gRPC, the valid values for HealthCheckCodes are from 0 to 99. The default value is 0. Value ranges are supported. You can specify at most 20 value ranges. Separate multiple value ranges with commas (,). Note This parameter takes effect only if you set HealthCheckEnabled to true and HealthCheckProtocol to HTTP, HTTPS, or gRPC.	200
HealthCheckHttpVersion	string	No	The HTTP version that is used for health checks. Valid values: HTTP1.0 HTTP1.1 Note This parameter takes effect only if you set HealthCheckEnabled to true and HealthCheckProtocol to HTTP or HTTPS.	HTTP1.1
HealthCheckInterval	integer	No	The interval at which health checks are performed. Unit: seconds. Valid values: 1 to 50. Note This parameter takes effect only if you set HealthCheckEnabled to true.	5
HealthCheckMethod	string	No	The HTTP method that is used for health checks. Valid values: GET: If the length of a response exceeds 8 KB, the response is truncated. However, the health check result is not affected. POST: gRPC health checks use the POST method by default. HEAD: HTTP and HTTPS health checks use the HEAD method by default. Note This parameter takes effect only if you set HealthCheckEnabled to true and HealthCheckProtocol to HTTP, HTTPS, or gRPC.	HEAD
HealthCheckPath	string	No	The URL that is used for health checks. The URL must be 1 to 80 characters in length, and can contain letters, digits, and the following special characters: `- / . % ? # & =`. It can also contain the following extended characters: `_ ; ~ ! ( ) * [ ] @ $ ^ : ' , +`. The URL must start with a forward slash (`/`). Note This parameter takes effect only if you set HealthCheckEnabled to true and HealthCheckProtocol to HTTP or HTTPS.	/test/index.html
HealthCheckProtocol	string	No	The protocol that you want to use for health checks. Valid values: HTTP: HTTP health checks simulate browser behaviors by sending HEAD or GET requests to probe the availability of backend servers. HTTPS: HTTPS health checks simulate browser behaviors by sending HEAD or GET requests to probe the availability of backend servers. HTTPS supports encryption and provides higher security than HTTP. TCP: TCP health checks send TCP SYN packets to a backend server to probe the availability of backend servers. gRPC: gRPC health checks send POST or GET requests to a backend server to check whether the backend server is healthy.	HTTP
HealthCheckTimeout	integer	No	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 This parameter takes effect only if you set HealthCheckEnabled to true.	3
HealthyThreshold	integer	No	The number of times that an unhealthy backend server must consecutively pass health checks before it can be declared healthy. In this case, the health check status of the backend server changes from fail to success. Valid values: 2 to 10.	4
UnhealthyThreshold	integer	No	The number of times that a healthy backend server must consecutively fail health checks before it can be declared unhealthy. In this case, the health check status of the backend server changes from success to fail. Valid values: 2 to 10.	4
StickySessionConfig	object	No	The configuration of session persistence.
Cookie	string	No	The cookie to be configured on the server. The cookie must be 1 to 200 characters in length and can contain only ASCII characters and digits. It cannot contain commas (,), semicolons (;), or space characters. It cannot start with a dollar sign ($). Note This parameter takes effect when the StickySessionEnabled parameter is set to true and the StickySessionType parameter is set to Server.	B490B5EBF6F3CD402E515D22B******
CookieTimeout	integer	No	The timeout period of a cookie. Unit: seconds. Valid values: 1 to 86400. Note This parameter takes effect when the StickySessionEnabled parameter is set to true and the StickySessionType parameter is set to Insert.	1000
StickySessionEnabled	boolean	No	Specifies whether to enable session persistence. Valid values: true false (default)	false
StickySessionType	string	No	The method that is used to handle a cookie. Valid values: Insert: inserts a cookie. ALB inserts a cookie (SERVERID) into the first HTTP or HTTPS response packet that is sent to a client. The next request from the client contains this cookie and the listener forwards this request to the recorded backend server. Server: rewrites a cookie. When ALB detects a user-defined cookie, it overwrites the original cookie with the user-defined cookie. Subsequent requests to ALB carry this user-defined cookie, and ALB determines the destination servers of the requests based on the cookies. Note This parameter takes effect when the StickySessionEnabled parameter is set to true for the server group.	Insert
ServerGroupId	string	Yes	The server group ID.	sgp-atstuj3rtop****
UpstreamKeepaliveEnabled	boolean	No	Specifies whether to enable persistent TCP connections.	true
ServiceName	string	No	This parameter is available only if the ALB Ingress controller is used. In this case, set this parameter to the name of the `Kubernetes Service` that is associated with the server group.	test2
UchConfig	object	No	The configurations of consistent hashing based on URLs.
Type	string	Yes	The type of the parameter. Only query strings are supported.	QueryString
Value	string	Yes	The value of the parameter used for consistent hashing.	abc
ConnectionDrainConfig	object	No	The configurations of connection draining. After connection draining is enabled, SLB remains data transmission for a period of time after a backend server is removed or declared unhealthy. Note Basic SLB instances do not support connection draining. Standard and WAF-enabled SLB instances support connection draining. Server groups of the server and IP types support connection draining. Server groups of the Function Compute type do not support connection draining.
ConnectionDrainEnabled	boolean	No	Specifies whether to enable connection draining. Valid values: true false	false
ConnectionDrainTimeout	integer	No	The timeout period of connection draining. Valid values: 0 to 900.	300
SlowStartConfig	object	No	The configurations of slow starts. After slow starts are enabled, ALB prefetches data to newly added backend servers. Requests distributed to the backend servers gradually increase. Note Basic ALB instances do not support slow starts. Standard and WAF-enabled ALB instances support slow starts. Server groups of the instance and IP types support slow starts. Server groups of the Function Compute type do not support slow starts. Slow start is supported only by the weighted round-robin scheduling algorithm.
SlowStartEnabled	boolean	No	Indicates whether slow starts are enabled. Valid values: true false	false
SlowStartDuration	integer	No	The duration of a slow start.	30
CrossZoneEnabled	boolean	No	Indicates whether cross-zone load balancing is enabled for the server group. Valid values: true (default) false Note Basic ALB instances do not support server groups that have cross-zone load balancing disabled. Only Standard and WAF-enabled ALB instances support server groups that have cross-zone load balancing. Cross-zone load balancing can be disabled for server groups of the server and IP type, but not for server groups of the Function Compute type. When cross-zone load balancing is disabled, session persistence cannot be enabled.	true

Response elements

Element	Type	Description	Example
	object	The response parameters.
JobId	string	The ID of the asynchronous job.	72dcd26b-f12d-4c27-b3af-18f6aed5****
RequestId	string	The request ID.	365F4154-92F6-4AE4-92F8-7FF3*****

Examples

Success response

JSON format

{
  "JobId": "72dcd26b-f12d-4c27-b3af-18f6aed5****",
  "RequestId": "365F4154-92F6-4AE4-92F8-7FF3*****"
}

Error codes

HTTP status code	Error code	Error message	Description
400	IncorrectStatus.ServerGroup	The status of %s [%s] is incorrect.	The status of %s [%s] is incorrect.
400	Mismatch.LoadBalancerEditionAndConnectionDrain	The %s and %s are mismatched.	The %s and %s are mismatched.
400	Mismatch.ServerGroupSchedulerAndSlowStartEnable	The %s and %s are mismatched.	The %s and %s are mismatched.
400	QuotaExceeded.ConnectionDrainTimeout	The quota of %s is exceeded, usage %s/%s.	The quota of %s is exceeded, usage %s/%s.
400	UnsupportedFeature.ConnectionDrain	The feature of %s is not supported.	The feature of %s is not supported.
400	QuotaExceeded.SlowStartDuration	The quota of %s is exceeded, usage %s/%s.	The quota of %s is exceeded, usage %s/%s.
400	UnsupportedFeature.SlowStart	The feature of %s is not supported.
400	Mismatch.LoadBalancerEditionAndSlowStartEnable	The %s and %s are mismatched.	The %s and %s are mismatched.
400	OperationDenied.UpstreamKeepaliveDisabled	The operation is not allowed because of UpstreamKeepaliveDisabled.	Updating not allowed Backend long connection is closed
400	OperationDenied.UpstreamKeepaliveEnabled	The operation is not allowed because of UpstreamKeepaliveEnabled.	Update not allowed to open Backend Long connection is in the open state
400	CloseUpstreamKeepaliveNotSupport	The param of UpstreamKeepalive is not Support.	close keepalive attribute for server group is not supported
404	ResourceNotFound.ServerGroup	The specified resource %s is not found.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.