# Failover (Deprecated)

#### Scenarios

When the production servers and disks in the primary AZ become faulty due to force majeure, users can make API calls to perform a failover for the replication consistency group and enable the DR servers and disks in the secondary AZ to ensure the service continuity.

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

Confirm with the customer service that servers and disks in the production AZ are faulty, and the deployed services are unavailable.

#### Procedure

1. Perform a failover for the replication consistency group.

   For details, see Performing a Failover for a Replication Consistency Group in the Elastic Volume Service API Reference.

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)