Changing a Cluster Instance Class

Precautions

• An instance cannot be deleted while its instance class is being changed.
• When the instance class is being changed, a primary/secondary switchover may occur once or twice and the database connection will be interrupted each time for up to 30s. You are advised to change the specifications during off-peak hours to reduce impacts and ensure that the service system of your client can reconnect to the database if the connection is interrupted.
• After the class of a cluster instance is changed, the system will change the value of net.maxIncomingConnections accordingly.
• A maximum of 16 shard nodes can be selected in each batch of class change.
• The classes of yearly/monthly instance shard nodes can only be upgraded or downgraded one at a time.
• If you forcibly change the class of an abnormal node in a DB instance, services may be interrupted.

Pre-check Items for Instance Class Change

• The instance status and the status of the node whose specifications are to be changed are normal.
• The primary/standby replication delay does not exceed 20s. (This pre-check item applies only to shard and config nodes.)

Changing dds mongos Class

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click Service List. Under Database, click Document Database Service to go to the DDS console.
4. On the Instances page, click the cluster instance name.
5. In the Node Information area on the Basic Information page, click the dds mongos tab, locate the dds mongos node, and click Change Instance Class in the Operation column.
6. On the displayed page, select the required specifications and new instance class and click Next.
7. On the displayed page, confirm the instance class.
   • If you need to modify your settings, click Previous to go back to the page for you to specify details.
   • If you do not need to modify your settings, click Submit to change the instance class.

8. View the results.
   • When the instance class is being changed, the status displayed in the Status column is Changing instance class. This process takes about 10 minutes.
   • In the upper right corner of the instance list, click to refresh the list. The instance status changes to Available.
   • In the Node Information area on the Basic Information page, click the dds mongos tab and view the new class.

Changing shard Class

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click Service List. Under Database, click Document Database Service to go to the DDS console.
4. On the Instances page, click the cluster instance name.
5. In the Node Information area on the Basic Information page, click the shard tab. You can change the class of a single shard or change the classes of multiple shards at a time.
   • Changing the class of a shard
     1. In the Operation column of the shard node, click Change Class.

     2. On the displayed page, select the required specifications and new class and click Next.
        Note

        The time required depends on the number of instance nodes whose specifications are to be changed. It takes about 5 to 10 minutes for each node. When the instance class is being changed, a primary/secondary switchover may occur once or twice and the database connection will be interrupted each time for up to 30s. Before the specification change, learn about Pre-check Items for Instance Class Change. You are advised to change the specifications during off-peak hours to reduce impacts and ensure that the service system of your client can reconnect to the database if the connection is interrupted.

   • Changing the classes of multiple shards in batches
     1. Select the target shards and click Change Classes in Batches.
     2. On the displayed page, select the required specifications and new class and click Next.
        Note

        The time required depends on the number of instance nodes whose class is to be changed. It takes about 5 to 10 minutes for each node. When the instance class is being changed, a primary/secondary switchover may occur once or twice and the database connection will be interrupted each time for up to 30s. Before the class change, learn about Pre-check Items for Instance Class Change. You are advised to change the class during off-peak hours to reduce impacts and ensure that the service system of your client can reconnect to the database if the connection is interrupted.

6. On the displayed page, confirm the instance class.
   • If you need to modify your settings, click Previous to go back to the page for you to specify details.
   • If you do not need to modify your settings, click Submit to change the instance class.

7. View the results.
   • When the instance class is being changed, the status displayed in the Status column is Changing instance class. This process takes about 25 to 30 minutes.
     Note

     High database load increases the specification change duration. You are advised to change the specifications during off-peak hours to reduce impacts.

   • In the upper right corner of the instance list, click to refresh the list. The instance status changes to Available.
   • Go to the Basic Information page of the cluster instance you scaled up, click the shard tab in the Node Information area, and view the new instance class.