Which requirement must be met before deploying data redundancy elimination in SD-WAN?

Data Redundancy Elimination (DRE) works by identifying and eliminating duplicate data patterns in traffic streams. For DRE to function optimally and detect redundancies effectively across a communication path, it requires symmetric routing to ensure both forward and reverse traffic flows traverse the same DRE-enabled devices.

Disabling shaping might be a QoS consideration, but it's not a prerequisite for the fundamental operation of data redundancy elimination.

While GRE tunnels can be part of an SD-WAN underlay, DRE is an optimization feature that works over the SD-WAN tunnels (often IPsec), and specifically requiring GRE tunnels is not a general prerequisite for DRE.

While a DRE feature template is required to configure and enable DRE on devices, this is a configuration step, not a fundamental networking requirement that must be met before deployment, like symmetric routing.