In a multi-region networking infrastructure in OCI, what could prevent workloads from communicating?

In a multi-region networking infrastructure in Oracle Cloud Infrastructure (OCI), effective communication between workloads relies heavily on the configuration of route tables and connectivity options. When the route table lacks rules for forwarding traffic to respective Dynamic Routing Gateways (DRGs), this creates a barrier to communication.

DRGs are essential for facilitating the flow of traffic between Virtual Cloud Networks (VCNs), especially when dealing with multi-region setups where workloads may reside in different VCNs across regions. If the route table does not explicitly define the pathways for traffic to go through these DRGs, then the workloads will not be able to route their traffic appropriately, leading to communication failures.

Understanding this, it is critical to ensure that every VCN's route table is configured with rules that allow traffic to be directed to the appropriate DRGs, thus enabling seamless communication between regions. Without these rules, even if other components like Internet gateways or Local Peering Gateways are correctly set up, the actual communication will still be obstructed due to lack of proper routing.