Add or remove nodes

Billing

Precautions

• You can add or remove read-only nodes only when no configuration changes are in progress for the cluster.

• You can remove multiple read-only nodes at the same time. However, to prevent operational errors, we recommend that you add or remove only one node at a time.

• Adding a read-only node takes about 5 minutes. This operation does not affect your database.

• Removing a read-only node briefly interrupts its connections. Other nodes are not affected. We recommend that you perform this operation during off-peak hours and ensure your application has an automatic reconnection mechanism. If your application connects to the cluster endpoint, PolarDB automatically removes the deleted node from the endpoint, so you do not need to change your application configuration.

Add a read-only node

1. Log on to the PolarDB console. In the navigation pane on the left, click Clusters. Select the cluster's region and then find the cluster.

2. Navigate to the Add/Remove Node wizard using either of the following methods:

   • In the Operation column, click Add/Remove Node.

   • Click the cluster ID. On the Basic Information page, in the database nodes section, click Add/Remove Node.

3. Select Add Node and click OK.

   Adding a node takes about 5 minutes. The default cluster endpoint automatically recognizes the new node for load balancing.

4. Click + Add Read-only Node, select a Switching Time, accept the terms of service, and then click Buy Now.

   Note

   • To add multiple nodes to your cluster at the same time, click + Add Read-only Node repeatedly.

   • For Switching Time, you can select Switch Now or Switch At. If you select Switch At, you can specify any time within the next 24 hours. The node-adding task completes within 30 minutes of the scheduled time. You can also view task details or cancel the task on the Scheduled Tasks page. For more information, see Scheduled Tasks.

Remove a read-only node

1. Log on to the PolarDB console. In the navigation pane on the left, click Clusters. Select the cluster's region and then find the cluster.

2. Navigate to the Add/Remove Node wizard using either of the following methods:

   • In the Operation column, click Add/Remove Node.

   • Click the cluster ID. On the Basic Information page, in the database nodes section, click Add/Remove Node.

3. Select Delete Node and click OK.

4. Click the icon next to the node you want to delete.

5. Accept the terms of service, and then click Buy Now.

   Note

   You can release subscription and pay-as-you-go read-only nodes at any time. After a node is released, billing for the node stops, and you may receive a refund.

API reference