Help Center/ GaussDB(DWS)/ API Reference/ API Description/ Cluster Management/ Performing Primary-Standby Restoration
Updated on 2024-04-18 GMT+08:00

Performing Primary-Standby Restoration

Function

This API is used to performing active-standby restoration. In the Unbalanced state, the number of primary instances on some nodes increases. As a result, the load pressure is high. In this case, the cluster is normal, but the overall performance is not as good as that in a balanced state. You can perform primary-standby restoration to change the cluster status to Available.

  • Only8.1.1.202 and later versions support primary-standby cluster restoration.

  • Cluster restoration interrupts services for a short period of time. The interruption duration depends on the service volume. You are advised to perform this operation during off-peak hours.

Call Method

For details, see Calling APIs.

URI

POST /v1.0/{project_id}/clusters/{cluster_id}/switchover
Table 1 URI parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

Project ID. For details about how to obtain the ID, see Obtaining Project ID.

cluster_id

Yes

String

Cluster ID. For details about how to obtain the ID, see Obtaining the Cluster ID.

Request Parameters

None

Response Parameters

None

Example Request

POST https://{Endpoint}/v1.0/89cd04f168b84af6be287f71730fdb4b/clusters/4ca46bf1-5c61-48ff-b4f3-0ad4e5e3ba90/switchover

Example Response

None

SDK Sample Code

The sample code is as follows:

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package com.huaweicloud.sdk.test;

import com.huaweicloud.sdk.core.auth.ICredential;
import com.huaweicloud.sdk.core.auth.BasicCredentials;
import com.huaweicloud.sdk.core.exception.ConnectionException;
import com.huaweicloud.sdk.core.exception.RequestTimeoutException;
import com.huaweicloud.sdk.core.exception.ServiceResponseException;
import com.huaweicloud.sdk.dws.v2.region.DwsRegion;
import com.huaweicloud.sdk.dws.v2.*;
import com.huaweicloud.sdk.dws.v2.model.*;


public class SwitchOverClusterSolution {

    public static void main(String[] args) {
        // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
        // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
        String ak = System.getenv("CLOUD_SDK_AK");
        String sk = System.getenv("CLOUD_SDK_SK");

        ICredential auth = new BasicCredentials()
                .withAk(ak)
                .withSk(sk);

        DwsClient client = DwsClient.newBuilder()
                .withCredential(auth)
                .withRegion(DwsRegion.valueOf("<YOUR REGION>"))
                .build();
        SwitchOverClusterRequest request = new SwitchOverClusterRequest();
        try {
            SwitchOverClusterResponse response = client.switchOverCluster(request);
            System.out.println(response.toString());
        } catch (ConnectionException e) {
            e.printStackTrace();
        } catch (RequestTimeoutException e) {
            e.printStackTrace();
        } catch (ServiceResponseException e) {
            e.printStackTrace();
            System.out.println(e.getHttpStatusCode());
            System.out.println(e.getRequestId());
            System.out.println(e.getErrorCode());
            System.out.println(e.getErrorMsg());
        }
    }
}
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# coding: utf-8

from huaweicloudsdkcore.auth.credentials import BasicCredentials
from huaweicloudsdkdws.v2.region.dws_region import DwsRegion
from huaweicloudsdkcore.exceptions import exceptions
from huaweicloudsdkdws.v2 import *

if __name__ == "__main__":
    # The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    # In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak = os.getenv("CLOUD_SDK_AK")
    sk = os.getenv("CLOUD_SDK_SK")

    credentials = BasicCredentials(ak, sk) \

    client = DwsClient.new_builder() \
        .with_credentials(credentials) \
        .with_region(DwsRegion.value_of("<YOUR REGION>")) \
        .build()

    try:
        request = SwitchOverClusterRequest()
        response = client.switch_over_cluster(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)
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package main

import (
	"fmt"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic"
    dws "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/dws/v2"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/services/dws/v2/model"
    region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/dws/v2/region"
)

func main() {
    // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak := os.Getenv("CLOUD_SDK_AK")
    sk := os.Getenv("CLOUD_SDK_SK")

    auth := basic.NewCredentialsBuilder().
        WithAk(ak).
        WithSk(sk).
        Build()

    client := dws.NewDwsClient(
        dws.DwsClientBuilder().
            WithRegion(region.ValueOf("<YOUR REGION>")).
            WithCredential(auth).
            Build())

    request := &model.SwitchOverClusterRequest{}
	response, err := client.SwitchOverCluster(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

For more SDK sample codes of programming languages, visit API Explorer and click the Sample Code tab. Example codes can be automatically generated.

Status Code

Status Code

Description

200

The active-standby restoration is successful.

400

Request error.

401

Authentication failed.

403

You do not have required permissions.

404

No resources found.

500

Internal server error.

503

The service was unavailable.