To ensure ongoing communication between a server and a storage network, the server should be connected to at least two separate:

Connecting to at least two separate switches provides network path redundancy. If one switch fails, the server can still communicate with the storage network through the second switch, ensuring high availability and ongoing communication critical for robust storage area networks (SANs) and network-attached storage (NAS) connectivity.

Power supplies provide power to the server, not communication redundancy for the storage network.

While connecting to multiple storage arrays can provide data redundancy, it doesn't directly ensure ongoing network communication between the server and the storage network in case of a switch failure.

ISLs (Inter-Switch Links) connect switches to each other, not servers to the storage network directly; while important for fabric redundancy, they don't replace the need for redundant server-to-switch connections.