Oracle Cloud Infrastructure 2022 Architect Professional — Question 7

A cloud engineer needs to enable routing between two Virtual Cloud Networks (VCN) from his tenancy. The VCNs are in the same region but in different compartments. After reviewing the IPv4 CIDR prefixes of the two VCNs, he notices that there are no overlapping CIDR blocks.
Which THREE are valid Oracle Cloud Infrastructure (OCI) options for connecting and routing between the two VCNs? (Choose three.)

Answer options

• A. Create two DRGs in the tenancy. Attach one VCN to one of the DRGs; attach the other VCN to the second DRG. In each one of the DRGs, create a Virtual Circuit Attachment. Select FastConnect Partner as the FastConnect type. Select any vendor from the list and complete the circuit at the partner site. Once the FastConnect IPv4 BGP field is in the UP state in each one of the Virtual Circuits, add a route rule in each one of the VCNs' route table to the other VCN using the DRG as the next hop.
• B. Create two DRGs in the tenancy. Attach one VCN to one of the DRGs; attach the other VCN to the second DRG. In each one of the DRGs, create a Remote Peering Connection (RPC). Establish a connection from one RPC to the other. In each one of the VCNs' route table, add a route rule to the other VCN using the DRG as the next hop.
• C. Create a DRG in the tenancy; add one of the VCN as a VCN attachment. In the other VCN, create a Local Peering Gateway (LPG). Peer the DRG to the LPG. In the VCN attached to the DRG, add a route rule in the route table that points to the DRG as the next hop. In the other VCN, add a route rule in the route table that points to the LPG as the next hop.
• D. Add an LPG to each one of the VCNs. In one of the LPG, establish a Peering Connection to the other LPG. In each one of the VCN route table, add a route rule to the other VCN using the LPG as the next hop.
• E. Create a DRG in the tenancy; add one of the VCNs as a VCN attachment. In the other VCN, create a Local Peering Gateway (LPG). Peer the DRG to the LPG. In the VCN attached to the DRG, enable BGP routing for the route to propagate to the VCN. In the other VCN add a route rule in the route table that points to the LPG as the next hop.
• F. Create a Dynamic Routing Gateway (DRG) in the tenancy, add the two VCNs as VCN attachments and add routes in each one of the VCN route tables with the DRG as the next hop for the CIDR prefix of the other VCN.

Correct answer: B, D, F

Explanation

Option B is valid because it uses Remote Peering Connections to connect the two DRGs, allowing routing between the VCNs. Option D is also correct as it employs Local Peering Gateways to establish a peering connection between the VCNs, enabling routing. Option F is valid since it involves a DRG with both VCNs attached, allowing for direct routing. Options A, C, and E are incorrect as they either involve unnecessary complexity or misconfigured components that do not suit this scenario.