Change the number of engine nodes - Lindorm

You can add or remove nodes for each engine of a Lindorm instance to match your business requirements.

Prerequisites

The instance is in the Running state.

Usage notes

No other specification changes can be performed on the instance while a node change is in progress. We recommend that you perform this operation during off-peak hours.
You must retain at least two nodes for each engine to ensure service continuity if one node becomes unavailable during operations and maintenance (O&M).
Instances that use local disks store three data replicas by default. To keep three replicas available when one node is unavailable, you must configure at least three nodes for these instances.
When you remove nodes, make sure that the remaining nodes can meet your business requirements. If you encounter issues, submit a ticket.

The following table summarizes minimum node requirements by service type.

Service type	Minimum nodes	Notes
Lindorm instance	2 per engine	General requirement
Lindorm instance (local disks)	3 per engine	Maintains three data replicas
Lindorm New Edition (production)	2	Nodes cannot be removed
Lindorm New Edition (test)	1	Nodes cannot be removed
LTS	3	Cannot remove nodes from a 3-node instance

Procedure

The procedure varies depending on the Service Type of your instance. For more information about how to view the service type, see View the series of an instance.

Common first step (all service types): Log on to the Lindorm console. In the upper-left corner of the page, select the region where the instance is deployed. On the Instances page, click the ID of the instance that you want to manage, or click Manage in the Actions column.

Lindorm instance

Change the number of nodes.
- Add a node: In the Configurations section, click Create Node in the Actions column for the target engine.
- Remove a node: In the Configurations section, click > Reduce Nodes in the Actions column for the target engine.
Important
To ensure that three data replicas remain available when one node is unavailable, you must configure at least three nodes for a Lindorm instance that uses local disks.
On the Upgrade/Downgrade or Upgrade/Downgrade page, specify the number of nodes and the storage capacity for the engine.

Note
For more information about how to determine the number of engine nodes, see Select a node specification and the number of nodes.
Agree to the terms of service, and then click Buy Now.

Lindorm New Edition instance

Important

You cannot remove nodes from a Lindorm New Edition instance. A production instance must contain at least two nodes and a test instance must contain at least one node.

In the Configurations section, click Create Node in the Actions column for the target engine.
On the Upgrade/Downgrade page, click the icon in the upper-right corner of the engine card, and then modify the number of engine nodes.
Agree to the terms of service, and then click Buy Now.

LTS

In the Configurations section, click Manage, and then select Reduce Nodes or Create Node from the drop-down list.
On the Upgrade/Downgrade or Change Specification page, specify the number of nodes.

Important
An LTS instance must contain at least three nodes. You cannot remove nodes from an instance that contains only three nodes.
Agree to the terms of service, and then click Buy Now.

After you submit the change

When the change is in progress, the instance enters the Changing Specifications state. The change is complete when the instance state returns to Running.

Note

The time required depends on the number of nodes being added or removed. In most cases, adding or removing one node takes 2 to 10 minutes. The time increases as more nodes are added or removed.