If an internal link led san valentine present for him here, you may wish to change the link to point directly to the intended article. The availability and accessibility of storage are critical concerns for enterprise computing. Modern enterprise computing often demands a much higher level of organization, flexibility and control. The storage can then be organized and managed as cohesive pools or tiers.
There are several popular uses for SANs in enterprise computing. A SAN is typically employed to consolidate storage. A SAN can also improve storage availability. Because a SAN is essentially a network fabric of interconnected computers and storage devices, a disruption in one network path can usually be overcome by enabling an alternative path through the SAN fabric. Thus, a single cable or device failure doesn’t leave storage inaccessible to enterprise workloads. IT’s ability to support enterprise workloads. But to appreciate the value of SAN technology, it’s important to understand how a SAN differs from traditional DAS.
With DAS, one or more disks are directly connected to a specific computer through a dedicated storage interface, such as SATA or SAS. A SAN operates in a profoundly different manner. The SAN interconnects all the disks into a dedicated storage area network. That dedicated network exists separate and apart from the common LAN. A SAN can support a huge number of storage devices, and storage arrays — specially designed storage subsystems — that support a SAN can scale to hold hundreds or even thousands of disks.
FC is a high-speed network noted for its high throughput and low latency, offering data rates up to 128 Gbps across metropolitan area distances — up to about 6 miles or 10 km — when optical fiber cabling and interfaces are used. The iSCSI is another type of network intended to connect computing with shared storage. It can run at speeds up to 100 Gbps but provides several simplifications for data center operators. Thus, enterprise workloads can potentially get faster access to astonishing volumes of storage. A SAN is generally perceived as a series of three distinct layers: a host layer, a fabric layer and a storage layer. The fabric layer represents the cabling and network devices that comprise the network fabric that interconnects the SAN hosts and SAN storage.
SAN networking devices within the fabric layer can include SAN switches, gateways, routers and protocol bridges. The storage layer is comprised of the various storage devices collected into various storage pools, tiers or types. Storage typically involves traditional magnetic HDDs but can also include SSDs along with optical media devices, such as CD and DVD drives, and tape drives. Most storage devices within a SAN are organized into physical RAID groups that can be employed to increase storage capacity, improve storage device reliability or both. A SAN also employs a series of protocols enabling software to communicate or prepare data for storage. Assemble and cable together all the hardware components and install the corresponding software.