You want to replicate data from an on-premises MySQL server to a MySQL DB system.

To replicate data from an on-premises MySQL server to a MySQL DB system running in Oracle Cloud Infrastructure (OCI), where the DB system is connected to a private subnet of a Virtual Cloud Network (VCN), you need to enable the DB system to communicate with the Internet securely. The correct configuration is tocreate a NAT gateway in the VCN and configure the DB system subnet to route Internet-bound traffic to the NAT gateway(Answer D).

NAT Gateway: A Network Address Translation (NAT) gateway enables instances in a private subnet to initiate outbound traffic to the Internet, but it prevents the Internet from initiating connections to those instances.

Route Table Configuration: You need to update the route table for the private subnet to direct traffic destined for the Internet to the NAT gateway.

Steps:

Create a NAT gateway in the OCI Console.

Update the route table associated with the private subnet to include a route rule that directs all Internet-bound traffic (0.0.0.0/0) to the NAT gateway.

References:

OCI NAT Gateway Documentation

Configuring Routing for Private Subnets