A storage-area network (SAN) is a dedicated high-velocity network (or subnetwork) that interconnects and presents shared pools of storage space products to multiple servers.
A SAN moves storage assets off the common user network and reorganizes them into an unbiased, high-performance network. This enables each server to gain access to shared storage as though it were a travel directly mounted on the server. Whenever a host wants to gain access to a storage gadget on the SAN, it transmits out a block-centered access obtain the storage device.
A storage-area network is normally assembled using three theory components: cabling, sponsor bus adapters (HBAs) and switches. Each switch and storage program on the SAN should be interconnected and the physical interconnections must support bandwidth amounts that may adequately handle peak data activities.
Storage-area networks are managed centrally, and Fibre Channel (FC) SANs have the trustworthiness of being expensive, difficult to control and complex. The emergence of iSCSI provides reduced these issues by encapsulating SCSI instructions into IP packets for transmitting over an Ethernet connection, instead of an FC connection. Rather than learning, managing two networks and building-- an Ethernet local-region network (LAN) for consumer conversation and an FC SAN for storage -- a business is now able to use its existing understanding and infrastructure for both LANs and SANs.
Virtual SAN
A virtual storage-area network (VSAN) is a software-defined storage offering that is implemented along with a hypervisor such as for example VMware ESXi or Microsoft Hyper-V. Virtual SANs yield numerous benefits such as simple management and scalability. Generally, VSANs are hardware-agnostic. So long as the storage equipment is recognized and backed by the hypervisor, the equipment can be utilized by the VSAN (although each vendor has its own requirements).
Unified SAN
Unified SAN is situated around the idea of unified storage space, which exposes file storage and block storage space through an individual device (usually an altered NAS appliance).
A unified SAN takes this idea a stage further by exposing not merely dedicated logical unit quantities (LUNs) -- like any additional SAN -- but file system-based, NAS-like storage.
Converged SAN
Storage-area networks are usually kept individual from Ethernet networks. A converged SAN runs on the common network infrastructure for network and SAN traffic to get rid of redundant infrastructure, and also to reduce price and complexity.
SANs often utilize FC, while data networks are often based on Ethernet. Converged SANs adopt Fibre Channel over Ethernet (FCoE), which encapsulates FC payloads into Ethernet frames. Converged SANs are nearly always predicated on 10 Gigabit Ethernet, and multiple network ports are sometimes bonded together to improve throughput.
SAN benefits and drawbacks
The primary benefit to utilizing a SAN is that raw storage is treated as a pool of resources which can be centrally managed and allocated on an as-needed basis. SANs are also extremely scalable because additional capability could be added as required.
The main drawbacks to SANs are cost and complexity. SAN hardware is commonly expensive, and building and owning a SAN takes a specialized skill set.
SAN vs. NAS
The conditions SAN and NAS are occasionally confused with each other since the acronyms are so similar. NAS includes a storage appliance that's plugged straight into a network change. Although there are exceptions, NAS appliances tend to be used as document servers.
Black Diamond Solutions is a leading SAN provider in Chicago, Illinois and the US as a whole.
http://blackdiamondsolutions.com/
