Virtual Private Cloud (VPC) networks support the ClassicLink feature. This feature allows classic network-connected Elastic Compute Service (ECS) instances to communicate with cloud resources deployed in VPC networks. Before you establish a ClassicLink connection, make sure that the ClassicLink feature is enabled.

Background information

The ClassicLink feature allows classic network-connected ECS instances to communicate with cloud resources such as ECS instances, ApsaraDB for RDS (RDS) instances, and Server Load Balancer (SLB) instances that are deployed in VPC networks. ECS instances in a VPC network can access only ECS instances in a classic network that is already connected to the VPC network. ECS instances in the VPC network cannot access other cloud resources in the classic network or ECS instances deployed outside the classic network. For more information, see Overview.
Note The ClassicLink feature is supported only in regions that support classic networks. For more information, see View privileges and quotas by resource type.


  1. Log on to the VPC console.
  2. On the top navigation bar, select the region where the VPC network is deployed.
  3. On the VPCs page, find the target VPC network and click Manage in the Actions column.
  4. In the upper-right corner of the VPC Details page, click Enable ClassicLink.
  5. In the Enable ClassicLink message, click OK.
    After ClassicLink is enabled, the status of ClassicLink in the VPC Details section changes to Enabled. Enable ClassicLink