A client has requested a new 4TB storage system. They need redundancy built in as well as some scalability. This should be attached to the current network, consisting of SAS and SCSI based servers, on

A Fiber Channel SAN is typically much more expensive and requires a specialized FC network, not just a copper gigabit network, making it unsuitable for a low-price, copper-based requirement.

Four independent 1TB NAS devices would provide 4TB but lack integrated redundancy across the system and would not be managed as a single scalable storage pool as efficiently as a SAN.

An iSCSI SAN leverages standard Ethernet for network connectivity, fitting the existing copper gigabit network, and uses more cost-effective SATA drives compared to FC or SAS. A RAID 5 configuration with five 1TB drives provides 4TB of redundant storage, and five empty slots offer future scalability, all at a significantly lower price point than Fiber Channel.

Direct Attached Storage (DAS) is not network-attached for multiple servers, limiting accessibility and scalability, and nine 300GB drives in RAID 5 would only yield 2.4TB, failing to meet the 4TB capacity requirement.