iSCSI Solutions : Storage Area Networks can be
Fibre Channel-based (FC) or IP-based (iSCSI). For Fibre Channel
SANs a separate network is required and consists of specialized
hardware (HBAs for hosts that require connectivity to the SAN
and SAN switches). iSCSI SANs can utilize pre-existing networks
but are best designed as dedicated IP networks to avoid
contention between storage and client/server traffic.
Regardless of whether the SAN is Fibre Channel or iSCSI-based,
SANs provide only for the consolidation of the physical storage
resources and in every other way resemble a Direct Attach
Storage (DAS) environment. Each server still owns its respective
file system and data is still shared by the general-purpose
server and must be backed up on a server-by-server basis.
SANs are beneficial when applications require
the speed of direct block translation and are typically
implemented for large-scale database applications.