Updating a Backend Server Group¶
Function¶
This API is used to update a backend server group.
Constraints¶
The backend server group can be updated only when the provisioning status of the associated load balancer is ACTIVE.
URI¶
PUT /v3/{project_id}/elb/pools/{pool_id}
Parameter | Mandatory | Type | Description |
|---|---|---|---|
pool_id | Yes | String | Specifies the backend server group ID. |
project_id | Yes | String | Specifies the project ID. |
Request Parameters¶
Parameter | Mandatory | Type | Description |
|---|---|---|---|
X-Auth-Token | Yes | String | Specifies the token used for IAM authentication. |
Parameter | Mandatory | Type | Description |
|---|---|---|---|
pool | Yes | UpdatePoolOption object | Specifies the backend server group. |
Parameter | Mandatory | Type | Description |
|---|---|---|---|
admin_state_up | No | Boolean | Specifies the administrative status of the backend server group. The value can only be updated to true. This parameter is unsupported. Please do not use it. |
description | No | String | Provides supplementary information about the backend server group. Minimum: 0 Maximum: 255 |
lb_algorithm | No | String | Specifies the load balancing algorithm used by the load balancer to route requests to backend servers in the associated backend server group. The value can be one of the following:
Note:
|
name | No | String | Specifies the backend server group name. Minimum: 0 Maximum: 255 |
session_persistence | No | Specifies the sticky session. | |
slow_start | No | UpdatePoolSlowStartOption object | Specifies slow start details. After you enable slow start, new backend servers added to the backend server group are warmed up, and the number of requests they can receive increases linearly during the configured slow start duration. This parameter can be used when the protocol of the backend server group is HTTP or HTTPS. An error will be returned if the protocol is not HTTP or HTTPS. |
member_deletion_protection_enable | No | Boolean | Specifies whether to enable removal protection for the load balancer.
Note Disable removal protection for all your resources before deleting your account. |
vpc_id | No | String | Specifies the ID of the VPC where the backend server group works. This parameter can be updated only when vpc_id is left blank. Minimum: 0 Maximum: 36 |
type | No | String | Specifies the type of the backend server group. Values:
Note: This parameter can be updated only when type is left blank. |
protection_reason | No | String | Specifies why the modification protection is enabled. Note: This parameter is valid only when protection_status is set to consoleProtection. If protection_status is set to nonProtection, the value of protection_reason is removed. The value can contain a maximum of 255 Unicode characters, excluding angle brackets (<>). Minimum: 0 Maximum: 255 |
Parameter | Mandatory | Type | Description |
|---|---|---|---|
cookie_name | No | String | Specifies the cookie name. The value can contain only letters, digits, hyphens (-), underscores (_), and periods (.). Note: This parameter will take effect only when type is set to APP_COOKIE. |
type | No | String | Specifies the sticky session type. The value can be SOURCE_IP, HTTP_COOKIE, or APP_COOKIE. Note:
|
persistence_timeout | No | Integer | Specifies the stickiness duration, in minutes. This parameter will not take effect when type is set to APP_COOKIE.
|
Parameter | Mandatory | Type | Description |
|---|---|---|---|
enable | No | Boolean | Specifies whether to enable slow start.
|
duration | No | Integer | Specifies the slow start duration, in seconds. The value ranges from 30 to 1200, and the default value is 30. Minimum: 30 Maximum: 1200 |
Response Parameters¶
Status code: 200
Parameter | Type | Description |
|---|---|---|
request_id | String | Specifies the request ID. The value is automatically generated. |
pool | Pool object | Specifies the backend server group. |
Parameter | Type | Description |
|---|---|---|
admin_state_up | Boolean | Specifies the administrative status of the backend server group. The value can only be true. This parameter is unsupported. Please do not use it. |
description | String | Provides supplementary information about the backend server group. |
healthmonitor_id | String | Specifies the ID of the health check configured for the backend server group. |
id | String | Specifies the backend server group ID. |
lb_algorithm | String | Specifies the load balancing algorithm used by the load balancer to route requests to backend servers in the associated backend server group. The value can be one of the following:
Note:
|
listeners | Array of ListenerRef objects | Specifies the IDs of the listeners with which the backend server group is associated. |
loadbalancers | Array of LoadBalancerRef objects | Specifies the IDs of the load balancers with which the backend server group is associated. |
members | Array of MemberRef objects | Specifies the IDs of the backend servers in the backend server group. |
name | String | Specifies the backend server group name. |
project_id | String | Specifies the project ID. |
protocol | String | Specifies the protocol used by the backend server group to receive requests. The value can be TCP, UDP, HTTP, HTTPS, or QUIC.
|
session_persistence | SessionPersistence object | Specifies the sticky session. |
ip_version | String | Specifies the IP address version supported by the backend server group. IPv6 is unsupported. Only v4 will be returned. |
slow_start | SlowStart object | Specifies slow start details. After you enable slow start, new backend servers added to the backend server group are warmed up, and the number of requests they can receive increases linearly during the configured slow start duration. This parameter can be used when the protocol of the backend server group is HTTP or HTTPS. An error will be returned if the protocol is not HTTP or HTTPS. |
member_deletion_protection_enable | Boolean | Specifies whether to enable removal protection.
Note Disable removal protection for all your resources before deleting your account. |
created_at | String | Specifies the time when a backend server group was created. The format is yyyy-MM-dd'T'HH:mm:ss'Z' (UTC time). This is a new field in this version, and it will not be returned for resources associated with existing dedicated load balancers and for resources associated with existing and new shared load balancers. |
updated_at | String | Specifies the time when when a backend server group was updated. The format is yyyy-MM-dd'T'HH:mm:ss'Z' (UTC time). This is a new field in this version, and it will not be returned for resources associated with existing dedicated load balancers and for resources associated with existing and new shared load balancers. |
vpc_id | String | Specifies the ID of the VPC where the backend server group works. |
type | String | Specifies the type of the backend server group. Values:
|
protection_status | String | Specifies the protection status. Value options:
|
protection_reason | String | Specifies why the modification protection is enabled. Note: This parameter is valid only when protection_status is set to consoleProtection. The value can contain a maximum of 255 Unicode characters, excluding angle brackets (<>). Minimum: 0 Maximum: 255 |
az_affinity | AzAffinity object | Specifies how AZ affinity is configured for the backend server group. This parameter is unsupported. Please do not use it. |
Parameter | Type | Description |
|---|---|---|
id | String | Specifies the listener ID. |
Parameter | Type | Description |
|---|---|---|
id | String | Specifies the load balancer ID. |
Parameter | Type | Description |
|---|---|---|
id | String | Specifies the backend server ID. |
Parameter | Type | Description |
|---|---|---|
cookie_name | String | Specifies the cookie name. The value can contain only letters, digits, hyphens (-), underscores (_), and periods (.). Note: This parameter will take effect only when type is set to APP_COOKIE. |
type | String | Specifies the sticky session type. The value can be SOURCE_IP, HTTP_COOKIE, or APP_COOKIE. Note:
|
persistence_timeout | Integer | Specifies the stickiness duration, in minutes. This parameter will not take effect when type is set to APP_COOKIE.
|
Parameter | Type | Description |
|---|---|---|
enable | Boolean | Specifies whether to enable slow start.
Default: false |
duration | Integer | Specifies the slow start duration, in seconds. The value ranges from 30 to 1200, and the default value is 30. Minimum: 30 Maximum: 1200 Default: 30 |
Parameter | Type | Description |
|---|---|---|
enable | Boolean | Specifies whether to enable AZ affinity for the backend server group. If this parameter is set to true, ELB forwards traffic across the backend servers in the same AZ as the load balancer. Constraints:
The value can be false (disabled) or true (enabled). |
az_minimum_healthy_member_percentage | Integer | Specifies a percentage that is used to determine the health of an AZ. If the percentage of healthy servers in the AZ of the load balancer falls below the specified value, az_unhealthy_fallback_strategy is triggered. az_minimum_healthy_member_percentage shows the ratio of healthy servers to total servers in a backend server group of an AZ. The number of healthy servers is rounded up. For example, in AZ A, if there are three backend servers in the backend server group and az_minimum_healthy_member_percentage is set to 66%, the number of healthy servers is rounded up to 2 (3 x 0.66 = 1.98). If there are fewer than two healthy servers in AZ A, az_unhealthy_fallback_strategy is triggered. If az_minimum_healthy_member_percentage is set to 67%, the number of healthy servers is rounded up to 3 (3 x 0.67 = 2.01). If there are fewer than three healthy servers in AZ A, az_unhealthy_fallback_strategy is triggered. Constraints:
Value range: an integer ranging from -1 to 100. -1 indicates that az_minimum_healthy_member_count takes effect. |
az_minimum_healthy_member_count | Integer | Specifies a number that is used to determine the health of an AZ. If the number of healthy servers in the AZ of the load balancer falls below the specified value, az_unhealthy_fallback_strategy is triggered. az_minimum_healthy_member_count shows the number of healthy servers to total servers in a backend server group of an AZ. Constraints:
Value range: an integer ranging from -1 to 10000. -1 indicates that az_minimum_healthy_member_percentage takes effect. |
az_unhealthy_fallback_strategy | String | Specifies how traffic will be distributed across backend servers in an AZ if the percentage or number of healthy servers in the AZ of the load balancer falls below the specified value. Value options:
The value can be forward_to_all_member_of_local_az, forward_to_healthy_member_of_remote_az, forward_to_all_healthy_member, or forward_to_all_member. Default value: forward_to_all_member_of_local_az |
Example Requests¶
PUT https://{ELB_Endpoint}/v3/99a3fff0d03c428eac3678da6a7d0f24/elb/pools/36ce7086-a496-4666-9064-5ba0e6840c75
{
"pool" : {
"name" : "My pool.",
"description" : "My pool update",
"lb_algorithm" : "LEAST_CONNECTIONS"
}
}
Example Responses¶
Status code: 200
Successful request.
{
"pool" : {
"type" : "",
"vpc_id" : "",
"lb_algorithm" : "LEAST_CONNECTIONS",
"protocol" : "TCP",
"description" : "My pool update",
"admin_state_up" : true,
"member_deletion_protection_enable" : false,
"loadbalancers" : [ {
"id" : "098b2f68-af1c-41a9-8efd-69958722af62"
} ],
"project_id" : "99a3fff0d03c428eac3678da6a7d0f24",
"session_persistence" : null,
"healthmonitor_id" : null,
"listeners" : [ {
"id" : "0b11747a-b139-492f-9692-2df0b1c87193"
}, {
"id" : "61942790-2367-482a-8b0e-93840ea2a1c6"
}, {
"id" : "fd8f954c-f0f8-4d39-bb1d-41637cd6b1be"
} ],
"members" : [ ],
"id" : "36ce7086-a496-4666-9064-5ba0e6840c75",
"name" : "My pool.",
"ip_version" : "dualstack"
},
"request_id" : "8f40128b-c72b-4b64-986a-f7e2c633d75f"
}
Status Codes¶
Status Code | Description |
|---|---|
200 | Successful request. |
Error Codes¶
See Error Codes.