# Planned Migration (Deprecated)

#### Scenarios

Production servers and production disks belong to the primary AZ, and DR servers and DR disks belong to the secondary AZ. Users can make API calls to perform a planned migration, for example, perform a primary/secondary AZ switchover for the replication consistency group and enable the servers and disks in the secondary AZ.

EVS replication APIs have been deprecated. If you need to use the replication function, see Storage Disaster Recovery Service User Guide and Storage Disaster Recovery Service API Reference.

#### Prerequisites

- The production server status is normal, and the deployed services are running properly.
- The target production servers have been temporarily stopped.
- The replication status of the replication consistency group is active, which means that data synchronization in all EVS replication pairs of the replication consistency group is complete.

#### Procedure

1. Perform a primary/secondary AZ switchover for the replication consistency group.

   For details, see Performing a Primary/Secondary Switchover for a Replication Consistency Group in the Elastic Volume Service API Reference.

   Performing a primary/secondary switchover for a replication consistency group takes a relative long period of time, and it takes about 10 seconds for the system to respond the request.

2. If Elastic Load Balancing (ELB) or EIPs are used, unbind the ELB or EIPs with the production servers and bind them to the DR servers.

   - For details about ELB, see Backend Server (Enhanced Load Balancer) in the Elastic Load Balancing User Guide.
   - For details about EIPs, see Elastic IP Address in the Virtual Private Cloud User Guide.
3. Verify that the DR server OSs can be normally started, deployed services are available, and the data is complete.

Parent topic: Managing EVS Replication (Deprecated)