Replacing a Node
Function
This API is used to replace a failed node.
If a node in an Elasticsearch or OpenSearch cluster is faulty, you can replace it to restore services.
The node replacement process is as follows:
-
Migrate data from the node that needs to be replaced to other available nodes.
-
Rebuild the node using the original ID, IP address, specifications, and AZ.
-
Add the new node into the cluster. The system automatically triggers a shard reallocation, migrating some of the shards to the new node.
This process does not interrupt services because data is migrated from the replaced node to other available nodes.
Constraints
-
Only one node can be replaced at a time. Each new node is rebuilt using the ID, IP address, specifications, and AZ of the node it is replacing.
-
The configurations you modified manually will not be retained after node replacement. For example, if you have manually added a return route for the original node, you need to add it again for the new node after the node replacement is complete.
-
If the node you want to replace is a data node or cold data node, pay attention to the following precautions:
-
When a data node or cold data node is replaced, its data is first migrated to other data nodes. This means the total number of data nodes and cold data nodes must be greater than the maximum number of index replicas plus 1.
-
Elasticsearch clusters whose version is earlier than 7.6.2 cannot have closed indexes. Otherwise, their data nodes or cold data nodes cannot be replaced.
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In the AZ that contains the data node or cold data node to be replaced, there has to be at least another data node or cold data node.
-
If the cluster has not master nodes, the total number of data nodes plus cold data nodes must be at least three.
-
The precautions above do not apply if you are replacing a faulty node, regardless of its type. This is because faulty nodes are not included in _cat/nodes.
Calling Method
For details, see Calling APIs.
Authorization Information
Each account has all the permissions required to call all APIs, but IAM users must be assigned the required permissions.
- If you are using role/policy-based authorization, see Permissions Policies and Supported Actions for details on the required permissions.
- If you are using identity policy-based authorization, the following identity policy-based permissions are required.
Action
Access Level
Resource Type (*: required)
Condition Key
Alias
Dependencies
css:cluster:upgradeCluster
Write
cluster *
-
- ecs:cloudServerFlavors:get
- evs:types:get
- kms:cmk:get
- iam:agencies:listAgencies
- iam:permissions:listRolesForAgency
- iam:permissions:listRolesForAgencyOnProject
- iam:agencies:pass
URI
PUT /v1.0/{project_id}/clusters/{cluster_id}/instance/{instance_id}/replace
| Parameter | Mandatory | Type | Description |
|---|---|---|---|
| project_id | Yes | String | Definition Project ID. For details about how to obtain the project ID and name, see Obtaining the Project ID and Name. Constraints N/A Range Project ID of an account. The value contains 32 characters, consisting of lowercase letters and digits. Default Value N/A |
| cluster_id | Yes | String | Definition ID of the cluster where nodes are to be replaced. For details about how to obtain the cluster ID, see Obtaining the Cluster ID. Constraints N/A Range The value is a UUID containing 36 characters. Default Value N/A |
| instance_id | Yes | String | Definition ID of the node to be replaced. Obtain the ID attribute in instances by referring to Querying Cluster Details. Constraints N/A Range N/A Default Value N/A |
Request Parameters
None
Response Parameters
Status code: 200
Request succeeded.
None
Example Requests
Replace a node.
PUT https://{Endpoint}/v1.0/{project_id}/clusters/4f3deec3-efa8-4598-bf91-560aad1377a3/instance/43e63449-339c-4280-a6e9-da36b0685995/replace?migrateData=true Example Responses
None
SDK Sample Code
The SDK sample code is as follows.
Java
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 | 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.css.v1.region.CssRegion; import com.huaweicloud.sdk.css.v1.*; import com.huaweicloud.sdk.css.v1.model.*; public class UpdateInstanceSolution { 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"); String projectId = "{project_id}"; ICredential auth = new BasicCredentials() .withProjectId(projectId) .withAk(ak) .withSk(sk); CssClient client = CssClient.newBuilder() .withCredential(auth) .withRegion(CssRegion.valueOf("<YOUR REGION>")) .build(); UpdateInstanceRequest request = new UpdateInstanceRequest(); request.withClusterId("{cluster_id}"); request.withInstanceId("{instance_id}"); try { UpdateInstanceResponse response = client.updateInstance(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()); } } } |
Python
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | # coding: utf-8 import os from huaweicloudsdkcore.auth.credentials import BasicCredentials from huaweicloudsdkcss.v1.region.css_region import CssRegion from huaweicloudsdkcore.exceptions import exceptions from huaweicloudsdkcss.v1 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.environ["CLOUD_SDK_AK"] sk = os.environ["CLOUD_SDK_SK"] projectId = "{project_id}" credentials = BasicCredentials(ak, sk, projectId) client = CssClient.new_builder() \ .with_credentials(credentials) \ .with_region(CssRegion.value_of("<YOUR REGION>")) \ .build() try: request = UpdateInstanceRequest() request.cluster_id = "{cluster_id}" request.instance_id = "{instance_id}" response = client.update_instance(request) print(response) except exceptions.ClientRequestException as e: print(e.status_code) print(e.request_id) print(e.error_code) print(e.error_msg) |
Go
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 | package main import ( "fmt" "github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic" css "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/css/v1" "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/css/v1/model" region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/css/v1/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") projectId := "{project_id}" auth, err := basic.NewCredentialsBuilder(). WithAk(ak). WithSk(sk). WithProjectId(projectId). SafeBuild() if err != nil { fmt.Println(err) return } hcClient, err := css.CssClientBuilder(). WithRegion(region.ValueOf("<YOUR REGION>")). WithCredential(auth). SafeBuild() if err != nil { fmt.Println(err) return } client := css.NewCssClient(hcClient) request := &model.UpdateInstanceRequest{} request.ClusterId = "{cluster_id}" request.InstanceId = "{instance_id}" response, err := client.UpdateInstance(request) if err == nil { fmt.Printf("%+v\n", response) } else { fmt.Println(err) } } |
More
For SDK sample code of more programming languages, see the Sample Code tab in API Explorer. SDK sample code can be automatically generated.
Status Codes
| Status Code | Description |
|---|---|
| 200 | Request succeeded. |
| 400 | Invalid request. The client should modify the request instead of re-initiating it. |
| 404 | The requested resource could not be found. The client should modify the request instead of re-initiating it. |
Error Codes
See Error Codes.
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