Create and manage clusters

A cluster is an OpenSearch execution unit composed of multiple nodes (Data Node, Cluster Manager Node) that performs indexing, search, and analysis on large-scale data. A cluster provides an integrated search and analytics environment that includes high-performance search processing, data durability, scalability, and security configuration, and supports stable exploration of data generated from various applications and systems.
The following describes how to create and manage OpenSearch clusters in the Advanced Managed Search service.

Create cluster

Create a new cluster. Depending on the environment, creating a cluster may take about 10 minutes.

note

• Even if you expand the volume after creating the cluster, the maximum IOPS remains fixed at the initially specified value.
• Set an appropriate volume size for stable performance.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. Click the [Get started] button to create a service agent for accessing Advanced Managed Search resources.

3. In the Clusters menu, click the [Create cluster] button.

4. Enter the information required to create the cluster and click the [Create] button.

   Item	Category	Description
   Basic settings	Cluster name	Enter the name of the cluster to create - Duplicate cluster names cannot be used within the same project - Example: my-cluster-01
   	OpenSearch version	Select the OpenSearch version - Supported OpenSearch versions
   Network settings	VPC	Select the network where the cluster will be configured - Using a VPC with two or more availability zones is recommended to maintain high availability of the cluster - Select from created user VPCs or create a new one and select it
   	Subnet	Select the subnet to which data nodes will be assigned - Select from created user subnets or create a new one and select it
   	Security group	Configure the security group to apply to the cluster - Select from created user security groups or create a new one and select it - For more information, see Security groups
   Data node settings	Number of specified availability zones	Check the number of availability zones and the availability zones of the subnet selected in Network settings
   	Instance type	Select the instance type - Each data node in the cluster runs with the specifications of the selected instance - The instance type cannot be changed after the cluster is created
   	Number of data nodes per availability zone	Enter the number of data nodes to distribute in each specified availability zone - Data node quota: up to 9 per project - For more information about the data node quota, see Quota * If 2 availability zones and 3 data nodes are specified, 3 data nodes are placed in each of the 2 availability zones Total number of data nodes: 6
   	Volume type / size per data node	Specify the volume type and size to assign to each data node - Volume type: only SSD is currently available - Volume size: from 50 GB to 1,600 GB * If 3 data nodes and a volume size of 50 GB are specified, 50 GB is assigned to each data node Total volume size: 150 GB
   	Maximum IOPS	Check the maximum IOPS determined according to the volume size
   Cluster manager node settings	Instance type	Select the instance type - Cluster manager nodes run with the specifications of the selected instance - The instance type cannot be changed after the cluster is created
   	Number of cluster manager nodes	Check the number of cluster manager nodes - For stable operation, the number of nodes is always maintained at 3.
   Master user settings	Master username	Check the master username - For convenience, the master username is fixed as admin
   Master user settings	Master password	Set the master password - Must include uppercase English letters, and only English letters, numbers, and special characters are allowed (8-16 characters)
   Master user settings	Confirm master password	Re-enter the value set as the master password

Manage clusters

View cluster list

You can view the list of clusters created in the project.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. In the Clusters menu, check the list of currently created clusters.

   Item	Description	Note
   Name	Name specified by the user when creating the cluster	Click the cluster name to view detailed information about the cluster
   ID	Resource ID of the cluster
   Status	Current status of the cluster	For detailed status values, see Cluster lifecycle and status
   Version	OpenSearch version in use
   Number of availability zones	Number of availability zones according to the network settings configured by the user when creating the cluster
   Number of data nodes	Number of data nodes created by the user when creating the cluster	Total number of data nodes: Number of availability zones * Number of data nodes
   Created at	Date and time when the cluster was created
   Created by	User who requested cluster creation

View cluster details

You can check information about clusters created in the project.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. In the Clusters menu, click the name of the cluster whose details you want to view.

3. Check detailed information in the tabs.

   Top information

   Item	Description	Note
   Status	Current status of the cluster	For detailed status values, see Cluster lifecycle and status
   OpenSearch version	OpenSearch version in use
   Endpoint	Access address for connecting to the OpenSearch cluster through API	Authentication is required when accessing the endpoint through the master user account set when creating the cluster or a user account with granted permissions
   OpenSearch dashboard	Address for connecting to OpenSearch dashboard	Log in with the master user account set when creating the cluster - See External access to OpenSearch Dashboard (nginx)

   Details tab

   Item	Information	Description
   Cluster	Cluster name	Name specified by the user when creating the cluster
   	Cluster ID	Resource ID of the cluster
   	Master user ID	Master user ID entered when creating the cluster
   	VPC	User VPC selected by the user when creating the cluster
   	Created by	User who requested cluster creation
   	Subnet	User subnet selected by the user when creating the cluster
   	Created at	Date and time when the cluster was created
   	Security group	List of security groups configured by the user when creating the cluster
   Data node	Number of availability zones	Number of availability zones according to the network settings configured by the user when creating the cluster
   	Number of data nodes per availability zone	Number of data nodes placed per availability zone and the total number of nodes - Total number of nodes: Number of availability zones * Number of nodes
   	Instance type	Instance specification of the data node selected by the user when creating the cluster
   	Total volume size (volume size per node)	Total volume size and the volume size allocated per node
   Cluster manager node	Instance type	Instance specification of the cluster manager node selected by the user when creating the cluster
   	Number of cluster manager nodes	Check the number of manager nodes and the availability zones where they are placed
   Logs	Collected logs	Check the types of logs being collected
   	View logs	Move to the log explorer of the Monitoring service to view logs

   Instances tab

   Item	Information	Description
   Data node	Name	Name created by KakaoCloud when the data node is created - You can check the data node name in the legend when viewing charts in the Monitoring tab
   	ID	Resource ID of the data node
   	Status	Current status of the data node - For detailed status values, see Data node lifecycle and status
   	Instance type	Instance specification of the data node selected by the user when creating the cluster
   	Availability zone	Availability zone where the data node is placed
   	Volume size	Volume size allocated to the data node
   Cluster manager node	Name	Name created by KakaoCloud when the cluster manager node is created - You can check the cluster manager node name in the legend when viewing charts in the Monitoring tab
   	ID	Resource ID of the cluster manager node
   	Status	Current status of the cluster manager node - For detailed status values, see Cluster manager node lifecycle and status
   	Instance type	Instance specification of the cluster manager node selected by the user when creating the cluster
   	Availability zone	Availability zone where the cluster manager node is placed

   Monitoring tab

   Category	Description
   Data period	Set the data period to display on monitoring graphs - 1 hour ago (default) / 3 hours ago / 12 hours ago / 1 day ago / 7 days ago
   Query items	Select monitoring query items - Cluster / Data Node / Cluster Manager Node - Select all (default) - Multiple items can be selected
   View mode	Set the monitoring graph view mode - One-column view, two-column view available
   Auto refresh interval	Set the auto refresh interval - No auto refresh (default) / 10 seconds / 30 seconds / 1 minute / 5 minutes
   Manual refresh	Refresh monitoring results by clicking the refresh button

   Monitoring data

   Item	Monitoring data	Description
   Cluster	Number of Shards by State	Number of shards in the cluster by state
   Cluster	Active Shards Percentage	Percentage of shards that are normally active out of all shards
   Cluster	Indexed Documents (5m Interval)	Number of documents successfully indexed in the last 5 minutes
   Cluster	Failed Indexed Documents (5m Interval)	Number of documents that failed indexing in the last 5 minutes
   Cluster	Search Queries latency	Average response latency of search queries
   Cluster	Search Queries per Second	Number of search queries processed per second
   Cluster	Total Active Documents	Total number of documents stored in the cluster and currently searchable
   Cluster	Thread Pool Queue Size	Number of tasks waiting in the OpenSearch thread pool
   Cluster	Thread Pool Rejected Request Count (5m Interval)	Number of requests rejected in the last 5 minutes due to thread pool capacity being exceeded
   Cluster	Circuit Breaker Trip Count per Second	Number of times per second the circuit breaker was triggered to protect memory
   Data Node	OpenSearch Process CPU Usage (%)	CPU usage of the OpenSearch process on the data node
   Data Node	System Memory Usage (%)	Overall system memory usage of the data node
   Data Node	System Memory Usage (Bytes)	Total system memory usage of the data node
   Data Node	Heap Usage (%)	Usage percentage of JVM heap memory on the data node
   Data Node	Heap Usage (Bytes)	Actual JVM heap memory usage of the data node
   Data Node	Young GC Count (1m Interval)	Number of Young GC occurrences on the data node in the last 1 minute
   Data Node	Old GC Count (1m Interval)	Number of Old GC occurrences on the data node in the last 1 minute
   Data Node	Disk Usage Watermark (%)	Displays the disk watermark threshold set in the cluster and the current disk usage of the data node as a percentage
   Data Node	Disk Usage Watermark (Bytes)	Displays the disk watermark threshold set in the cluster and the current disk usage of the data node in bytes
   Cluster Manager Node	OpenSearch Process CPU Usage (%)	CPU usage of the OpenSearch process on the cluster manager node
   Cluster Manager Node	System Memory Usage (%)	System memory usage of the cluster manager node
   Cluster Manager Node	System Memory Usage (Bytes)	Total system memory usage of the cluster manager node
   Cluster Manager Node	Heap Usage (%)	Usage percentage of JVM heap memory on the cluster manager node
   Cluster Manager Node	Heap Usage (Bytes)	Actual JVM heap memory usage of the cluster manager node
   Cluster Manager Node	Young GC Count (1m Interval)	Number of Young GC occurrences on the cluster manager node in the last 1 minute
   Cluster Manager Node	Old GC Count (1m Interval)	Number of Old GC occurrences on the cluster manager node in the last 1 minute

Extend volume

If storage space becomes insufficient due to increasing data, you can expand the volume size allocated to data nodes to maintain stable cluster operation.
Volume expansion is performed without cluster interruption or node restart, and can dynamically increase storage space without affecting existing data or search services.

note

Volume expansion means increasing storage capacity, and CPU and memory resources according to the instance specification are not changed. If search performance improvement is required, consider expanding data nodes as well.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. In the Clusters menu, select the cluster to expand.

3. Click the [Extend volume] button located at the upper right.

4. In Volume expansion settings, expand the volume and click the [Save] button.

   Item	Description
   Cluster name	Check the name of the selected cluster
   Number of data nodes	Check the total number of data nodes in the selected cluster
   Current total volume size	Check the current total volume size and the volume size per data node
   Data node volume size	Specify the volume size to expand per data node

Expand cluster

To respond to increasing search traffic or expanding indexed data, you can increase the number of data nodes through cluster expansion.
When the cluster is expanded, OpenSearch shard reallocation is automatically performed, and temporary performance fluctuations may occur during this process.
Expansion can improve search throughput and indexing performance, and enables stable service operation even in large-scale data workload environments.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. In the Clusters menu, select the cluster to expand.

3. Click the [Expand cluster] button located at the upper right.

4. In Cluster expansion settings, expand the number of data nodes and click the [Save] button.

   Item	Description
   Cluster name	Check the name of the selected cluster
   Number of availability zones	Check the number of availability zones of the selected cluster
   Availability zone	Check the availability zones of the selected cluster
   Current total number of data nodes	Check the current total number of data nodes and the number of data nodes per availability zone
   Number of data nodes	Specify the number of data nodes to expand per availability zone

Delete cluster

You can delete a cluster that is no longer in use.

caution

Be careful, because the nodes and allocated volumes in the deleted cluster are fully released and cannot be recovered.

1. Go to KakaoCloud console > Analytics > Advanced Managed Search.

2. In the Clusters menu, select the cluster to delete.

3. In the Delete cluster pop-up window, enter the name of the cluster to delete and click the [Delete] button.