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Server Load Balancer:CreateVServerGroup

Last Updated:Mar 04, 2026

Creates a vServer group and adds backend servers to the vServer group.

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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:CreateVServerGroup

create

Instance

acs:ecs:{#regionId}:{#accountId}:instance/{#InstanceId}

*LoadBalancer

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

  • slb:tag
  • slb:tag
  • slb:tag
None

Request parameters

Parameter

Type

Required

Description

Example

Tag

array<object>

No

The tags.

object

No

The tags.

Key

string

No

The key of tag N. Valid values of N: 1 to 20. The tag key cannot be an empty string.

The tag key can be up to 64 characters in length, and cannot contain http:// or https://. The tag key cannot start with aliyun or acs:.

TestKey

Value

string

No

The tag value. Valid values of N: 1 to 20. The tag value can be an empty string.

The tag value can be up to 128 characters in length and cannot start with acs: or aliyun. The tag value cannot contain http:// or https://.

TestValue

RegionId

string

Yes

The ID of the region where the SLB instance is deployed.

cn-hangzhou

LoadBalancerId

string

Yes

The ID of the Server Load Balancer (SLB) instance.

lb-bp1qjwo61pqz3ahl******

VServerGroupName

string

No

The name of the vServer group.

The name must be 1 to 80 characters in length, and can contain letters, digits, hyphens (-), forward slashes (/), periods (.),and underscores (_).

Group1

BackendServers

string

No

The backend servers that you want to add. Configure the following parameters:

  • ServerId: required. The ID of the backend server. Specify the ID in a string. You can specify the ID of an Elastic Compute Service (ECS) instance, an elastic network interface (ENI), or an elastic container instance. If you set ServerId to the ID of an ENI or an elastic container instance, you must configure the Type parameter.

  • Weight: the weight of the backend server. Valid values: 0 to 100. Default value: 100. If you set the weight of a backend server to 0, no requests are forwarded to the backend server.

  • Description: optional. The description of the backend server. Specify the description in a string. The description must be 1 to 80 characters in length, and can contain letters, digits, hyphens (-), forward slashes (/), periods (.), and underscores (_).

  • Type: the type of the backend server. Valid values:

    • ecs (default): ECS instance

    • eni: ENI.

    • eni: elastic container instance.

Note

You can specify ENIs and elastic container instances as backend servers only for high-performance SLB instances.

  • ServerIp: The IP address of the ECS instance or ENI.

  • Port: the backend port.

Examples:

  • Add an ECS instance:

    [{ "ServerId": "i-xxxxxxxxx", "Weight": "100", "Type": "ecs", "Port":"80","Description":"test-112" }]

  • Add an ENI:

    [{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168.**.**", "Port":"80","Description":"test-112" }]

  • Add an ENI with multiple IP addresses:

    [{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168.**.**", "Port":"80","Description":"test-113" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166.**.**", "Port":"80","Description":"test-113" }]

  • Add an elastic container instance:

    [{ "ServerId": "eci-xxxxxxxxx", "Weight": "100", "Type": "eci", "ServerIp": "192.168.**.**", "Port":"80","Description":"test-114" }]

Note

You can add only running backend servers to SLB instances. You can specify at most 20 backend servers.

[{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "192.168.**.**", "Port":"80","Description":"test-112" },{ "ServerId": "eni-xxxxxxxxx", "Weight": "100", "Type": "eni", "ServerIp": "172.166.**.**", "Port":"80","Description":"test-113" }]

Response elements

Element

Type

Description

Example

object

VServerGroupId

string

The ID of the vServer group.

rsp-cige6******

RequestId

string

The ID of the request.

9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C

BackendServers

object

BackendServer

array<object>

The list of backend servers.

object

The backend servers.

Type

string

The type of backend server. Valid values:

  • ecs (default): ECS instance

  • eni: elastic network interface (ENI)

  • eci: elastic container instance

eni

Weight

integer

The weight of the backend server.

100

Description

string

The description of the vServer group.

vServer group

Port

integer

The port that is used by the backend server.

70

ServerId

string

The ID of the ECS instance or ENI.

eni-hhshhs****

Examples

Success response

JSON format

{
  "VServerGroupId": "rsp-cige6******",
  "RequestId": "9DEC9C28-AB05-4DDF-9A78-6B08EC9CE18C",
  "BackendServers": {
    "BackendServer": [
      {
        "Type": "eni",
        "Weight": 100,
        "Description": "vServer group",
        "Port": 70,
        "ServerId": "eni-hhshhs****"
      }
    ]
  }
}

Error codes

HTTP status code

Error code

Error message

Description

400 LBNotSupportIpv6Backend The specified loadbalancer does not support ipv6 backend.
400 Mismatched.ZoneId The zone of the server is not matched with the cloud box loadbalancer.
400 InvalidBackendServers.ServerIpConflict %s.
400 OperationUnsupported.CreateVServerGroup This type of backend server is not allowed to attached to singleTunnel or anyTunnel lb.
400 IncorrectStatus.RSByPassToas %s.
400 BackendServer.InvalidType The specified Type is invalid.
400 BackendServer.ServerRegionIdNotEqual The specified ServerRegionId must be equal.
400 OperationFailed.InvalidCen The cen related with this loadbalancer is invalid.
400 IncorrectStatus.CenNotAssociated The action is invalid because the loadbalancer is not associated with cen.
400 InvalidBackendServers.MissingCenBandWidth The bandwidth is missing between loadbalancer and backendServers in cen.
400 InvalidBackendServers.VpcNotInCen The BackendServers is not in the cen associated with the loadbalancer.
400 InvalidServerId.NotExist The specified ServerId is not exist.
400 MissingParameter.ServerRegionId The parameter ServerRegionId is required.
400 MissingParameter.VbrId The parameter VbrId is required.
400 InvalidParameter.ServerRegionId The parameter ServerRegionId is invalid for crossborder.
400 InvalidVbrId.NotInCen The VbrId is not in the cen associated with the loadbalancer.
400 InvalidParameter.ZoneNotSupport The zone does not support the parameter %s.
400 NetworkConflict %s.
400 InvalidParam.TagValue %s.
400 InvalidParam.TagKey %s.
400 SizeLimitExceeded.Tag %s.
400 MissingParam.TagKey The param MissingParam.TagKey is missing.
400 VpcSystemBusy Invoke vpc system busy, please retry later.
400 OperationFailed.Endpoint The operation failed because of the RegionId is unavailable in this endpoint. endpoint error
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.