Compute
Elastic Cloud Server
Huawei Cloud Flexus
Bare Metal Server
Auto Scaling
Image Management Service
Dedicated Host
FunctionGraph
Cloud Phone Host
Huawei Cloud EulerOS
Networking
Virtual Private Cloud
Elastic IP
Elastic Load Balance
NAT Gateway
Direct Connect
Virtual Private Network
VPC Endpoint
Cloud Connect
Enterprise Router
Enterprise Switch
Global Accelerator
Management & Governance
Cloud Eye
Identity and Access Management
Cloud Trace Service
Resource Formation Service
Tag Management Service
Log Tank Service
Config
OneAccess
Resource Access Manager
Simple Message Notification
Application Performance Management
Application Operations Management
Organizations
Optimization Advisor
IAM Identity Center
Cloud Operations Center
Resource Governance Center
Migration
Server Migration Service
Object Storage Migration Service
Cloud Data Migration
Migration Center
Cloud Ecosystem
KooGallery
Partner Center
User Support
My Account
Billing Center
Cost Center
Resource Center
Enterprise Management
Service Tickets
HUAWEI CLOUD (International) FAQs
ICP Filing
Support Plans
My Credentials
Customer Operation Capabilities
Partner Support Plans
Professional Services
Analytics
MapReduce Service
Data Lake Insight
CloudTable Service
Cloud Search Service
Data Lake Visualization
Data Ingestion Service
GaussDB(DWS)
DataArts Studio
Data Lake Factory
DataArts Lake Formation
IoT
IoT Device Access
Others
Product Pricing Details
System Permissions
Console Quick Start
Common FAQs
Instructions for Associating with a HUAWEI CLOUD Partner
Message Center
Security & Compliance
Security Technologies and Applications
Web Application Firewall
Host Security Service
Cloud Firewall
SecMaster
Anti-DDoS Service
Data Encryption Workshop
Database Security Service
Cloud Bastion Host
Data Security Center
Cloud Certificate Manager
Edge Security
Situation Awareness
Managed Threat Detection
Blockchain
Blockchain Service
Web3 Node Engine Service
Media Services
Media Processing Center
Video On Demand
Live
SparkRTC
MetaStudio
Storage
Object Storage Service
Elastic Volume Service
Cloud Backup and Recovery
Storage Disaster Recovery Service
Scalable File Service Turbo
Scalable File Service
Volume Backup Service
Cloud Server Backup Service
Data Express Service
Dedicated Distributed Storage Service
Containers
Cloud Container Engine
SoftWare Repository for Container
Application Service Mesh
Ubiquitous Cloud Native Service
Cloud Container Instance
Databases
Relational Database Service
Document Database Service
Data Admin Service
Data Replication Service
GeminiDB
GaussDB
Distributed Database Middleware
Database and Application Migration UGO
TaurusDB
Middleware
Distributed Cache Service
API Gateway
Distributed Message Service for Kafka
Distributed Message Service for RabbitMQ
Distributed Message Service for RocketMQ
Cloud Service Engine
Multi-Site High Availability Service
EventGrid
Dedicated Cloud
Dedicated Computing Cluster
Business Applications
Workspace
ROMA Connect
Message & SMS
Domain Name Service
Edge Data Center Management
Meeting
AI
Face Recognition Service
Graph Engine Service
Content Moderation
Image Recognition
Optical Character Recognition
ModelArts
ImageSearch
Conversational Bot Service
Speech Interaction Service
Huawei HiLens
Video Intelligent Analysis Service
Developer Tools
SDK Developer Guide
API Request Signing Guide
Terraform
Koo Command Line Interface
Content Delivery & Edge Computing
Content Delivery Network
Intelligent EdgeFabric
CloudPond
Intelligent EdgeCloud
Solutions
SAP Cloud
High Performance Computing
Developer Services
ServiceStage
CodeArts
CodeArts PerfTest
CodeArts Req
CodeArts Pipeline
CodeArts Build
CodeArts Deploy
CodeArts Artifact
CodeArts TestPlan
CodeArts Check
CodeArts Repo
Cloud Application Engine
MacroVerse aPaaS
KooMessage
KooPhone
KooDrive

Scaling In an OpenSearch Cluster

Updated on 2025-01-23 GMT+08:00

If a cluster can process current traffic without fully utilizing its resources, you can scale in the cluster to cut costs.

Scenario

CSS supports multiple scale-in methods, as described in Table 1.

Table 1 Scaling in an Elasticsearch cluster

Scenario

Description

Details

Reducing nodes randomly

Randomly removes some of the nodes of a cluster, so that it is less costly to keep it running.

Reducing Nodes Randomly

Removing specified nodes

Removes specified nodes of a cluster, so that it is less costly to keep it running.

Removing Specified Nodes

Constraints

  • To reduce the impact on services, you are advised to perform scale-in during off-peak hours.
  • During a scale-in, the data on the nodes to be removed needs to be migrated to other nodes. The timeout threshold for data migration is five hours. If data migration is not complete within 5 hours, the cluster scale-in fails. If the cluster stores large amounts of data, you are advised to break down the scale-in task into multiple batches, and complete each batch one at a time.
  • Ensure that the disk usage after scale-in is less than 80% and each AZ has at least one node of each type.
  • In a cross-AZ cluster, the difference between the numbers of the same type nodes in different AZs cannot exceed 1.
  • For a cluster without master nodes, the number of removed data nodes plus cold data nodes in a scale-in must be fewer than half of the original data nodes plus cold data nodes, and the number of remaining data nodes plus cold data nodes after a scale-in must be greater than the maximum number of index replicas.
  • For a cluster with master nodes, the number of removed master nodes in a scale-in must be fewer than half of the original master nodes. After scale-in, there has to be an odd number of master nodes, and there has to be at least three of them.
  • For a cluster without master nodes, scale-in is allowed only if the number of data nodes plus cold data nodes is at least three. For a cluster with master nodes, this number must be at least two if you want to be able to perform a scale-in. If you want to reduce cluster nodes even though your cluster does not meet these criteria, you can simply create a new cluster. You can migrate the data of your cluster by following the procedures described in Backing up and Restoring the Data of an Elasticsearch Cluster.
  • In each cluster, the number of nodes supported by each node type varies, depending on the types of nodes used in that cluster. For details, see Table 2.
    Table 2 Number of nodes of different types allowed in a single cluster

    Node Type

    Node Quantity

    ess

    ess: 1-32

    ess, ess-master

    ess: 1-200

    ess-master: an odd number ranging from 3 to 9

    ess, ess-client

    ess: 1-32

    ess-client: 1-32

    ess, ess-cold

    ess: 1-32

    ess-cold: 1-32

    ess, ess-master, ess-client

    ess: 1-200

    ess-master: an odd number ranging from 3 to 9

    ess-client: 1-32

    ess, ess-master, ess-cold

    ess: 1-200

    ess-master: an odd number ranging from 3 to 9

    ess-cold: 1-32

    ess, ess-client, ess-cold

    ess: 1-32

    ess-client: 1-32

    ess-cold: 1-32

    ess, ess-master, ess-client, ess-cold

    ess: 1-200

    ess-master: an odd number ranging from 3 to 9

    ess-client: 1-32

    ess-cold: 1-32

    NOTE:
    • ess: data node, which is the default node type that is mandatory for cluster creation. The other three node types are optional.
    • ess-master: master node
    • ess-client: client node
    • ess-cold: cold data node

Prerequisites

  • The cluster is in the Available state and has no ongoing tasks.
  • All mission-critical data has been backed up before a cluster scale-in. This is to prevent data loss.

Reducing Nodes Randomly

  1. Log in to the CSS management console.
  2. In the navigation pane, choose a cluster type. The cluster management page is displayed.
  3. In the cluster list, select the target cluster, and choose More > Modify Configuration in the Operation column. The Modify Configuration page is displayed.
  4. Click the Scale Cluster tab.
  5. Click Scale in to set parameters.
    Table 3 Reducing nodes randomly

    Parameter

    Description

    Action

    Select Scale in.

    Resources

    Shows the change of resources for this scale-in operation.

    Agency

    When a node is deleted, NICs are released. This means you need to have VPC permissions. Select an IAM agency to grant the current account the permission to access and use VPC.

    • This parameter is available only when the new IAM plane is connected.
    • If you are configuring an agency for the first time, click Automatically Create IAM Agency to create css-upgrade-agency.
    • If there is an IAM agency automatically created earlier, you can click One-click authorization to have the permissions associated with the VPC Administrator role or the VPC FullAccess system policy deleted automatically, and have the following custom policies added automatically instead to implement more refined permissions control.
      "vpc:subnets:get",
      "vpc:ports:*"
    • To use Automatically Create IAM Agency and One-click authorization, the following minimum permissions are required:
      "iam:agencies:listAgencies",
      "iam:roles:listRoles",
      "iam:agencies:getAgency",
      "iam:agencies:createAgency",
      "iam:permissions:listRolesForAgency",
      "iam:permissions:grantRoleToAgency",
      "iam:permissions:listRolesForAgencyOnProject",
      "iam:permissions:revokeRoleFromAgency",
      "iam:roles:createRole"
    • To use an IAM agency, the following minimum permissions are required:
      "iam:agencies:listAgencies",
      "iam:agencies:getAgency",
      "iam:permissions:listRolesForAgencyOnProject",
      "iam:permissions:listRolesForAgency"

    Nodes

    Reduce the number of nodes in the Nodes column. You can change multiple node types at the same time.

    For the value range of node quantity for each node type, see Table 2.

    Figure 1 Scaling in a cluster
  6. Click Next.
  7. Confirm the information and click Submit.
  8. Click Back to Cluster List to switch to the Clusters page. The Task Status is Scaling in. When Cluster Status changes to Available, the cluster has been successfully scaled in.

Removing Specified Nodes

  1. Log in to the CSS management console.
  2. In the navigation pane, choose a cluster type. The cluster management page is displayed.
  3. In the cluster list, select the target cluster, and choose More > Modify Configuration in the Operation column. The Modify Configuration page is displayed.
  4. On the Modify Configuration page, click the Scale In tab.
  5. Set scale-in parameters.
    Table 4 Removing specified nodes

    Parameter

    Description

    Agency

    When a node is deleted, NICs are released. This means you need to have VPC permissions. Select an IAM agency to grant the current account the permission to access and use VPC.

    • This parameter is available only when the new IAM plane is connected.
    • If you are configuring an agency for the first time, click Automatically Create IAM Agency to create css-upgrade-agency.
    • If there is an IAM agency automatically created earlier, you can click One-click authorization to have the permissions associated with the VPC Administrator role or the VPC FullAccess system policy deleted automatically, and have the following custom policies added automatically instead to implement more refined permissions control.
      "vpc:subnets:get",
      "vpc:ports:*"
    • To use Automatically Create IAM Agency and One-click authorization, the following minimum permissions are required:
      "iam:agencies:listAgencies",
      "iam:roles:listRoles",
      "iam:agencies:getAgency",
      "iam:agencies:createAgency",
      "iam:permissions:listRolesForAgency",
      "iam:permissions:grantRoleToAgency",
      "iam:permissions:listRolesForAgencyOnProject",
      "iam:permissions:revokeRoleFromAgency",
      "iam:roles:createRole"
    • To use an IAM agency, the following minimum permissions are required:
      "iam:agencies:listAgencies",
      "iam:agencies:getAgency",
      "iam:permissions:listRolesForAgencyOnProject",
      "iam:permissions:listRolesForAgency"

    Node Type

    Expand the node type that needs be changed to show all nodes under it. Select the nodes you want to remove.

  6. Click Next.
  7. Confirm the change information and click Submit. In the confirm dialog box, choose to migrate data, which helps to prevent data loss, and click OK.

    During data migration, the system migrates all data from the to-be-removed nodes to the remaining nodes, and removes these nodes upon completion of the data migration. If the data on the to-be-removed nodes has replicas on other nodes, data migration can be skipped and the cluster change can be completed faster.

  8. Click Back to Cluster List to switch to the Clusters page. The Task Status is Scaling in. When Cluster Status changes to Available, the cluster has been successfully scaled in.

We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out more

Feedback

Feedback

Feedback

0/500

Selected Content

Submit selected content with the feedback