ReplaceServersInServerGroup - Server Load Balancer - Alibaba Cloud Documentation Center

Replaces backend servers in a server group.

Operation description

ReplaceServersInServerGroup 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, it indicates that the server group is being modified.
- If a server group is in the Available state, it indicates that the server group is running.
You can call the ListServerGroupServers operation to query the status of a backend server.
- If a backend server is in the Replacing state, it indicates that the server is being removed from the server group and a new server is added to the server group.
- If a backend server is in the **Available** state, it indicates that the server is running.

Debugging

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer.

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
alb:ReplaceServersInServerGroup	update	All Resources *	none	none

Request parameters

Parameter	Type	Required	Description	Example
ServerGroupId	string	Yes	The ID of the server group. Note You cannot perform this operation on a server group of the Function type.	sgp-5114d593o96qxy****
AddedServers	array<object>	Yes	The backend servers. You can specify at most 200 servers in each call.
	object	Yes	The configurations of the backend server.
Description	string	No	The description of the backend server. The description must be 2 to 256 characters in length, and cannot start with http:// or https://.	test
Port	integer	Yes	The port used by the backend server in the server group. Valid values: 1 to 65535. You can specify at most 200 servers in each call.	80
ServerId	string	Yes	The ID of the backend server. You can specify at most 200 servers in each call. If the server group is of the Instance type, set ServerId to the ID of a resource of the Ecs, Eni, or Eci type. If the server group is of the Ip type, set ServerId to IP addresses. Note You cannot perform this operation on a server group of the Function Compute type. You can call the ListServerGroups operation to query the type of server groups.	i-bp1f9kdprbgy9uiu****
ServerIp	string	No	The IP address of the elastic network interface (ENI) in exclusive mode.	192.168.1.1
ServerType	string	Yes	The type of backend server. You can specify at most 200 servers in each call. Valid values: Ecs: Elastic Compute Service (ECS) instance Eni: ENI Eci: elastic container instance	Ecs
Weight	integer	No	The weight of the backend server. You can specify at most 200 servers in each call. Valid values: 0 to 100. Default value: 100. If the value is set to 0, no requests are forwarded to the server.	100
RemovedServers	array<object>	Yes	The backend servers that you want to remove.
	object	Yes	The configurations of the backend servers that you want to remove.
ServerId	string	Yes	The ID of the backend server. You can specify at most 200 servers in each call. If the server group is of the Instance type, set ServerId to the ID of a resource of the Ecs, Eni, or Eci type. If the server group is of the Ip type, set ServerId to IP addresses. Note You cannot perform this operation on a server group of the Function Compute type. You can call the ListServerGroups operation to query the type of server groups.	ecs-bp1ac9uozods2uc****
ServerIp	string	No	The IP address of the ENI in exclusive mode.	192.168.1.12
ServerType	string	Yes	The type of backend server. You can specify at most 200 servers in each call. Valid values: Ecs: ECS instance Eni: ENI Eci: elastic container instance	ecs
Port	integer	Yes	The port that is used by the backend server. Valid values: 1 to 65535. You can specify at most 200 servers in each call.	81
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.	593B0448-D13E-4C56-AC0D-FDF0FDE0E9A3
DryRun	boolean	No	Specifies whether to perform only a dry run, without performing the actual request. Valid values: true: performs a dry run. 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

Response parameters

Parameter	Type	Description	Example
	object	The response parameters.
JobId	string	The asynchronous task ID.	72dcd26b-f12d-4c27-b3af-18f6aed5****
RequestId	string	The request ID.	365F4154-92F6-4AE4-92F8-7FF34B540710

Examples

Sample success responses

JSONformat

{
  "JobId": "72dcd26b-f12d-4c27-b3af-18f6aed5****",
  "RequestId": "365F4154-92F6-4AE4-92F8-7FF34B540710"
}

Error codes

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

Change history

Change time	Summary of changes	Operation
2024-03-04	The Error code has changed	View Change Details
2024-01-29	The Error code has changed	View Change Details
2024-01-24	The Error code has changed	View Change Details
2024-01-18	The Error code has changed	View Change Details
2023-07-20	The Error code has changed	View Change Details

HTTP status code	Error code	Error message	Description
400	ResourceQuotaExceeded.ServerAddedNum	The quota of %s is exceeded for resource %s, usage %s/%s.	The quota of %s is exceeded for resource %s. Usage: %s/%s.
400	IncorrectStatus.ServerGroup	The status of %s [%s] is incorrect.	The status of %s [%s] is incorrect.
400	Conflict.BackendServer	There is already %s having the same configuration with %s.	There is already %s having the same configuration with %s.
400	DuplicatedParam.BackendServer	The param of %s is duplicated.	The param of %s is duplicated.
400	OperationDenied.EciNotSupportJobType	The operation is not allowed because of eci not support job type.	The operation is not allowed because of eci not support job type.
400	Mismatch.ServerType	The %s is mismatched for %s and %s.	-
400	ResourceInConfiguring	The specified resource of %s is being configured. Please try again later.	-
400	ResourceQuotaExceeded.LoadBalancerServersNum	The quota of %s is exceeded for resource %s, usage %s/%s.	The quota of %s is exceeded for resource %s. Usage: %s/%s.
400	ResourceInConfiguring.BackendServer	The specified resource of %s is being configured, please try again later.	The specified resource of %s is being configured, please try again later.
400	IdempotentParameterMismatch	The request uses the same client token as a previous, but non-identical request. Do not reuse a client token with different requests, unless the requests are identical.	The request uses the same client token as a previous, but non-identical request. Do not reuse a client token with different requests, unless the requests are identical.
404	ResourceNotFound.ServerGroup	The specified resource %s is not found.	The specified resource %s is not found.
404	ResourceNotFound.Ecs	The specified resource %s is not found.	The specified resource %s is not found.
404	ResourceNotFound.Eci	The specified resource %s is not found.	The specified resource %s is not found.
404	ResourceNotFound.Eni	The specified resource %s is not found.	The specified resource %s is not found.
404	ResourceNotFound.BackendServer	The specified resource %s is not found.	The specified resource %s is not found.