You are using a Windows Server 2012 in your on-premises location as a customer gateway. You’ve set up the Virtual Private gateway and the VPN connection. You have also set up the VPN configuration on the Windows Server 2012 machine. But when you check the status of the tunnel in the AWS Console, it still shows as down. What needs to be done to ensure that the connection is up and active?

Answer options:

A.Issue a ping command request from the Windows Server 2012 device.
B.From the AWS Console, choose the VPN connection, choose Actions->Bringup tunnel
C.From the AWS Console, choose the Virtual Private gateway, choose Actions->Bringup tunnel
D.Ensure BGP routing protocol is set up on the Windows Server 2012 device.

Answer – A
This is also given in the AWS Documentation. You have to initiate a request from the Customer gateway device.
Step 6: Test the VPN Connection
"To test that the VPN connection is working correctly, launch an instance into your VPC, and ensure that it does not have an Internet connection. After you`ve launched the instance, ping its private IP address from your Windows server. The VPN tunnel comes up when traffic is generated from the customer gateway. Therefore the ping command also initiates the VPN connection".
Options B and C are invalid because no such options are available.
Option D is invalid because this is not the right setup.
For more information on setting up Windows Server 2012 as the customer gateway, please refer to the below URL:
https://docs.aws.amazon.com/AmazonVPC/latest/NetworkAdminGuide/customer-gateway-windows-2012.html