A large electrical appliance firm is using AWS Cloud infrastructure for deploying application servers. It has created 3 VPC R&D, VPC Production & VPC IT. VPC IT has shared services servers deployed which need to have communication with servers in all three VPC.As per corporate guidelines, VPC R&D & VPC Production should be able to communicate with VPC IT, but there should not be any communication between VPC R&D & VPC Production. To support future demand in the number of VPC, the Transit gateway is deployed to have communication between these VPC.Which of the following route table configuration on Transit Gateway will you design to meet this requirement?

Answer options:

A.Create Two Routing tables in Transit Gateway. Associate VPC R&D & VPC IT attachments to one route table having routes propagated from each VPC. Associate VPC Production & VPC IT attachments to one route table having routes propagated from each VPC.B.Create Two Routing tables in Transit Gateway. Associate VPC R&D, VPC Production attachments to the route table having routes propagated from VPC IT. Associate VPC IT attachments with route tables having propagated routes from VPC R&D & VPC Production.
C.Create Two Routing tables in Transit Gateway. Associate VPC R&D, VPC Production attachments to the route table having static default route. Associate VPC IT attachments with route tables having propagated routes from VPC R&D & VPC Production.
D.Create Two Routing tables in Transit Gateway. Associate VPC R&D, VPC Production attachments to default route table having route propagation enabled. Associate VPC IT attachments with route tables having propagated routes from VPC R&D & VPC Production.

Correct Answer – B
Transit Gateway can be used for isolated shared services between multiple VPCs. For this, two routing tables can be created in Transit Gateway. First, the route table would have a route table with routes propagated from VPC R&D & VPC Production attachments.Other route tables would have a route table with routes propagated from VPC IT.
Option A is incorrect as For Transit Gateway, each attachment can be associated only to one route table. In the above case, VPC IT cannot be associated with two route tables.
Option C is incorrect as with the static Default route. Both VPC R&D & PC Finance will be able to communicate with each other.
Option D is incorrect as with the default route table, VPC R&D & VPC Production will be able to communicate with each other.
For more information on AWS Transit Gateway, refer to the following URL
https://docs.aws.amazon.com/vpc/latest/tgw/transit-gateway-isolated-shared.html