Which of the following is a requirement for redundant controllers in a BE connectivity setup?

In a BE (Back End) connectivity setup for a storage environment, having redundant controllers is essential for ensuring high availability and continuous operation. The requirement that they must have multiple active I/O paths is crucial because it enhances fault tolerance and load-balancing capabilities. This configuration allows data traffic to flow through different paths, which means if one path or controller goes down, others can still maintain the connectivity and functionality of the system.

Active I/O paths are vital for redundancy because they prevent a single point of failure from disrupting access to data. If the redundant controllers are not configured with multiple active I/O paths, the system would be vulnerable to downtime should a failure occur along the only available path.

Other options, while having their own merits, do not meet the same level of necessity in ensuring effective redundancy. For instance, being connected to a single fabric may simplify connectivity but does not enable the same level of fault tolerance. Connecting solely to primary storage or not utilizing diverse power sources may also compromise the overall resilience and operational integrity of the infrastructure.