Adding Coordinator Nodes for an Instance (Distributed)

Scenarios

As the instance deployment time and data increase, the database performance and storage will gradually reach the bottleneck. Adding nodes can improve the instance performance and storage capacity. You can only add nodes for distributed GaussDB instances that are deployed independently.

Precautions

The scaling duration depends on the amount of data. The default timeout period is seven days. When an instance is being scaled out, the instance is available, but you are not allowed to perform other operations on the console. If you need to perform any operations, submit a service ticket.
You can flexibly add coordinator nodes (CNs) or shards as needed. It is recommended that the number of CNs of a GaussDB instance do not exceed twice the number of shards.
Instances can be scaled out only when they are in the Available state.
You can add up to 64 CNs at a time, but the system supports no more than 256 CNs in total.

Billing

Billing Mode	Impact on Fees
Yearly/Monthly	After a CN is added, you will be billed for the new CN based on the time remaining in the requested period of your instance. You need to pay for the difference in price based on the remaining period. Example (The prices below are for reference only. The actual prices are displayed on the console.) Suppose you purchased a one-month, enterprise-edition distributed instance of V2.0-8.210 (configurations: 3 shards, 3 replicas, 3 CNs; instance specifications: dedicated, 8 vCPUs \| 64 GB; storage: ultra-high I/O, 120 GB) on June 1, 2025. The instance price was $19,752 USD/month. On June 15, 2025, you added a CN (specifications: dedicated, 8 vCPUs \| 64 GB) for the instance. Its price was $1,640 USD/month. Price difference = Fee of the new CN x Remaining period The remaining period in the formula is the number of remaining days in each calendar month divided by the maximum number of days in the calendar month. In this example, the remaining period and price difference are calculated as follows: Remaining period = 15 (Remaining days in June)/30 (Maximum number of days in June) = 0.5 Price difference = 1640 x 0.5 = $820 USD
Pay-per-use	Added CNs are billed by the hour. For details, see Product Pricing Details.

Billing Mode

Impact on Fees

Yearly/Monthly

After a CN is added, you will be billed for the new CN based on the time remaining in the requested period of your instance.

You need to pay for the difference in price based on the remaining period.

Example (The prices below are for reference only. The actual prices are displayed on the console.)

Suppose you purchased a one-month, enterprise-edition distributed instance of V2.0-8.210 (configurations: 3 shards, 3 replicas, 3 CNs; instance specifications: dedicated, 8 vCPUs | 64 GB; storage: ultra-high I/O, 120 GB) on June 1, 2025. The instance price was $19,752 USD/month.

On June 15, 2025, you added a CN (specifications: dedicated, 8 vCPUs | 64 GB) for the instance. Its price was $1,640 USD/month.

Price difference = Fee of the new CN x Remaining period

The remaining period in the formula is the number of remaining days in each calendar month divided by the maximum number of days in the calendar month.

In this example, the remaining period and price difference are calculated as follows:

Remaining period = 15 (Remaining days in June)/30 (Maximum number of days in June) = 0.5
Price difference = 1640 x 0.5 = $820 USD

Pay-per-use

Added CNs are billed by the hour. For details, see Product Pricing Details.

Procedure

Log in to the management console.
Click in the upper left corner and select a region and project.
Click in the upper left corner of the page and choose Databases > GaussDB.
On the Instances page, click the name of the target instance.
On the Basic Information page, click Add in the Coordinator Nodes field.
Specify the number of CNs to be added, the subnet, and the AZ.

Figure 1 Adding coordinator nodes
- If single-AZ deployment is specified during instance creation, CNs are only added to the AZ you specified.
- You can assign a different subnet for new CNs, though the instance's current subnet is recommended. If you want to use another subnet, ensure that it can communicate with the subnet of the instance. Otherwise, the scale-out will fail. You can select up to two different subnets for nodes, but their settings must be identical. If they differ, the nodes might not be able to communicate with each other.
Click Next.
Confirm the information and click Submit.
Check the result.

On the Instances page, check that the instance is in the Adding CNs state during the scale-out. After the instance status changes to Available, click the instance name. On the Basic Information page, check that the number of CNs matches the required quantity.