• Elastic Load Balancing

elb
  1. Help Center
  2. Elastic Load Balancing
  3. API Reference
  4. Enhanced Load Balancer APIs
  5. Member (Backend Server)
  6. Querying Backend Servers

Querying Backend Servers

Function

This API is used to query backend servers in a specific backend server group. Filter query and pagination query are supported.

URI

GET /v2.0/lbaas/pools/{pool_id}/members

Table 1 Parameter description

Parameter

Type

Mandatory

Description

pool_id

Uuid

Yes

Specifies the backend server group ID.

Constraints

Parameters marker, limit, and page_reverse are used for pagination query. Parameters marker and page_reverse take effect only when they are used together with parameter limit.

Request

  • Request parameters
    Table 2 Parameter description

    Parameter

    Type

    Mandatory

    Description

    marker

    String

    No

    Specifies the ID of the backend server from which pagination query starts, that is, the ID of the last backend server on the previous page. If this parameter is not specified, the first page will be queried.

    This parameter must be used together with limit.

    limit

    Int

    No

    Specifies the number of backend servers on each page.

    The value ranges from 0 to intmax.

    page_reverse

    Bool

    No

    Specifies the page direction. The value can be true or false, and the default value is false. The last page in the list requested with page_reverse set to false will not contain the "next" link, and the last page in the list requested with page_reverse set to true will not contain the "previous" link.

    This parameter must be used together with limit.

    id

    Uuid

    No

    Specifies the backend server ID.

    tenant_id

    String (255)

    No

    Specifies the ID of the project where the backend server is used.

    name

    String (255)

    No

    Specifies the backend server name.

    address

    String (64)

    No

    Specifies the private IP address of the backend server.

    protocol_port

    Int

    No

    Specifies the protocol and port number of the backend server.

    subnet_id

    Uuid

    No

    Specifies the ID of the subnet where the backend server works.

    admin_state_up

    Bool

    No

    Specifies the administrative status of the backend server.

    The value can be true or false.

    NOTE:

    This field can be used during creation and update and its actual value depends on whether the backend server exists. If the backend server exists, the value is true. Otherwise, the value is false.

    weight

    Int

    No

    Specifies the weight of the backend server.

  • Example request
    GET https://{Endpoint}/v2.0/lbaas/pools/5a9a3e9e-d1aa-448e-af37-a70171f2a332/members

Response

  • Response parameters
    Table 3 Parameter description

    Parameter

    Type

    Description

    members

    List

    Lists backend servers in the backend server group. For details, see Table 4.

    Table 4 members field description

    Parameter

    Type

    Description

    id

    Uuid

    Specifies the backend server ID.

    tenant_id

    String (255)

    Specifies the ID of the project where the backend server is used.

    name

    String (255)

    Specifies the backend server name.

    address

    String (64)

    Specifies the private IP address of the backend server. This IP address must be in the subnet specified by subnet_id.

    This parameter can be set only to the IP address of the primary NIC, for example, 192.168.3.11.

    protocol_port

    Int

    Specifies the protocol and port number of the backend server. The port number ranges from 1 to 65535.

    subnet_id

    Uuid

    Specifies the ID of the subnet where the backend server works. The private IP address of the backend server is in this subnet.

    IPv6 subnets are not supported.

    admin_state_up

    Bool

    Specifies the administrative status of the backend server. The value can be true or false.

    Currently, the value can only be true.

    NOTE:

    This field can be used during creation and update and its actual value depends on whether the backend server exists. If the backend server exists, the value is true. Otherwise, the value is false.

    weight

    Int

    Specifies the weight of the backend server. The value ranges from 0 to 100.

    If the value is 0, the backend server will not accept new requests. The default value is 1.

    operating_status

    String (16)

    Specifies the health check result of the backend server. The value can be one of the following:

    • ONLINE: The health check is successfully conducted and the backend server is running properly.
    • OFFLINE: The health check is abnormal and the backend server is running improperly. The load balancer stops distributing traffic to this server until it recovers.
    • NO_MONITOR: No health check is conducted. No health checks are configured, or the value of admin_state_up is false.

    members_links

    List

    Provides links to the previous or next page during pagination query, respectively.

    This parameter exists only in the response body of pagination query. For details, see Table 5.

    Table 5 members_links field description

    Parameter

    Type

    Description

    href

    String

    Provides links to the previous or next page during pagination query, respectively.

    rel

    String (255)

    Specifies the prompt of the previous or next page. The value can be next or previous.

    • next: indicates the URL of the next page.
    • previous: indicates that the URL of the previous page.
  • Example response
    {
        "members": [
            {
                "address": "10.0.0.8",
                "admin_state_up": true,
                "id": "9a7aff27-fd41-4ec1-ba4c-3eb92c629313",
                "protocol_port": 80,
                "subnet_id": "013d3059-87a4-45a5-91e9-d721068ae0b2",
                "tenant_id": "1a3e005cf9ce40308c900bcb08e5320c",
                
                "weight": 1,
                "name": "member-name"
            }
        ]
    }

Response Codes

For details, see HTTP Status Codes for Enhanced Load Balancers.