Free Amazon ANS-C01 Actual Exam Questions - Question 1 Discussion
engineer must connect the eu-west-1 and eu-central-1 Regions to the company headquarters and
branch office, respectively.
The network engineer created a production VPC, named Prod A, with a CIDR block of 10.0.0.0/16.
Prod A runs in an account in eu-west-1. The network engineer then created another production VPC,
named Prod B, with a CIDR block of 10.1.0.0/16. Prod В runs in a different account in eu-central-1.
The network engineer performed the following steps to try to achieve the required connectivity:
1. Created one transit gateway in each Region
2. Shared and accepted the transit gateways with the production accounts in both Regions
3. Configured the peering attachment between both transit gateways
4. Attached both VPCs to the respective Region transit gateway
5. Created both transit gateway route tables and associated the attachments with the route tables
6. Configured a static route in both transit gateway route tables to send traffic to the remote VPC in
the other Region
7. Activated route propagation on the VPC route tables in each Region
After the configuration, the network engineer tried to connect from Prod A to Prod B. However, the
connection was unsuccessful.
What should the network engineer do to achieve the required connectivity?
C/D? The question says the VPC CIDRs are 10.0.0.0/16 and 10.1.0.0/16, but option C suggests a route for 10.0.0.0/8, which seems way too broad and could cause routing conflicts. So I’d rule out C. For D, enabling dynamic propagation between transit gateway route tables makes sense because static routes might not update properly across regions. If the TGW route tables don’t share routes dynamically, that could explain the connectivity issue. So D feels like the proper fix here to ensure routes propagate correctly between the transit gateways themselves.
Seems like the missing piece is route propagation between the transit gateways themselves, not just within each VPC. D looks like the fix here.
B imo, static routes can conflict with route propagation in transit gateway tables.
D imo, the issue seems to be with how routes are propagated. Dynamically propagating routes between the production VPCs using transit gateway route tables should fix the connection problem.