Which of the below mentioned options is a valid entry for the main route table in this scenario?

A user has created a VPC with CIDR 20.0.0.0/16 using the wizard. The user has created a public subnet CIDR (20.0.0.0/24. and VPN only subnets CIDR (20.0.1.0/24. along with the VPN gateway (vgw-12345. to connect to the user’s data center.

Which of the below mentioned options is a valid entry for the main route table in this scenario?
A . Destination: 20.0.0.0/24 and Target: vgw-12345
B . Destination: 20.0.0.0/16 and Target: ALL
C . Destination: 20.0.1.0/16 and Target: vgw-12345
D . Destination: 0.0.0.0/0 and Target: vgw-12345

View Answer

Answer: D

Explanation:

The main route table came with the VPC, and it also has a route for the VPN-only subnet. A custom route table is associated with the public subnet. The custom route table has a route over the Internet gateway (the destination is 0.0.0.0/0, and the target is the Internet gateway). If you create a new subnet in this VPC, it’s automatically associated with the main route table, which routes its traffic to the virtual private gateway. If you were to set up the reverse configuration (the main route table with the route to the Internet gateway, and the custom route table with the route to the virtual private gateway), then a new subnet automatically has a route to the Internet gateway. http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Route_Tables.html