API Gateway:Dedicated instance clusters

Overview

Individual dedicated instances provide limited performance. If your business requirements cannot be met even by a highest-specification dedicated instance, you can cluster multiple dedicated instances to share the workload. You can cluster only instances of the same type and specification in the same region by way of domain name system (DNS) resolution. For information about the specification limits of dedicated instances, see Dedicated instances.

Basic operations

Create a dedicated instance cluster

1. Log on to the API Gateway console. In the left-side navigation pane, click Clusters.

2. On the page that appears, click Create Cluster. In the Create Cluster dialog box, specify the Name and Description parameters, and then click Confirm.

3. View the created cluster. The cluster is in the Ready state.

Add instances to a cluster

1. Find the cluster that you created and click Manage Instances in the Actions column.

2. On the page that appears, click Add Instance and specify an instance to add.

   Note

   1. When the cluster is in the Ready state, you can specify only one dedicated instance to add. The cluster uses the configurations of this instance as its own configurations, including the instance specification, version, and type.

   2. The first instance to add can have API groups. After the instance is added to the cluster, the API groups belong to the cluster.

3. Click Add. The system creates resources and uses the configurations of the added instance to initialize the cluster. After the cluster is initialized, it enters the Running state.

4. (Optional) Add more instances to the cluster. You can add multiple instances at a time.

   Note

   The instances that you want to add must use the same configurations as the cluster. Otherwise, the following errors may be reported:

   1. The shared or serverless instance cannot be added to the cluster.

   2. The instance that you want to add is of a different version. In this case, submit a ticket to have your instance updated.

   3. The instance that you want to add is of a different specification and cannot be added.

   4. The instance that you want to add is of a different type and cannot be added.

   5. The instance that you want to add has API groups and cannot be added.

   6. The instance that you want to add has different configurations for Inbound IPv6 Traffic, Outbound IPv6 Traffic, or Calls from API Gateway and cannot be added.

   7. The instance that you want to add has different configurations for HTTPS Security Policy, VPC for Access to Dedicated Instance, IPv6 Access Control, IPv4 Access Control, or Custom Private CIDR Block and these configurations will be overwritten by the corresponding cluster configurations after addition.

Modify the cluster configurations

1. Find the cluster that you want to manage in the cluster list and click Manage Instances in the Actions column.

2. On the page that appears, click Modify in the upper-right corner to modify the basic information of the cluster, including the name and description.

3. Modify other configurations, such as HTTPS Security Policy and VPC for Access to Dedicated Instance. The modification applies to all dedicated instances in the cluster.

4. Wait until all modifications are applied as expected.

Remove instances from a cluster

1. Find the cluster that you want to manage in the cluster list and click Manage Instances in the Actions column.

2. Select the instances that you want to remove in the Dedicated Instances list, and then click Remove Instance in the upper-right corner.

   Note

   1. During the process of removal, you cannot change the cluster configurations, add instances to, or remove other instances from the cluster.

   2. If the cluster has an API group, you cannot remove all dedicated instances from the cluster.

Usage notes

1. You can add dedicated instances of the api.s2.large.x4 or higher specifications.

2. You can add up to 20 dedicated instances to a single cluster. If you want to add more instances, submit a ticket to apply for a quota increase.

3. When you create an API group, you can specify a dedicated instance cluster as the instance to which the API group belongs. You cannot create API groups in a cluster that has the following ongoing operations: configuration change, instance addition, and instance removal.

4. You can migrate API groups from other API Gateway instances to a dedicated instance cluster.

5. If a new egress IP address is also added after you add a dedicated instance to a cluster, you must add the new egress IP address to the whitelist of your backend service to prevent connectivity issues.

6. When you add or remove a dedicated instance, DNS resolution records are added to or removed from the domain names of the API groups in the cluster. The time to live (TTL) of the DNS resolution records is 60 seconds.