Storage Area Network Benefits - IBM TotalStorage DS300 Best Practices Manual

1.1 Storage Area Network benefits

SANs create new methods of attaching storage to servers. These new methods
can enable great improvements in both availability and performance. Today's
SANs are used to connect shared storage arrays and tape libraries to multiple
servers, and are used by clustered servers for failover. They can interconnect
mainframe disk or tape to mainframe servers where the SAN switch devices
allow the intermixing of open systems (Windows®, AIX®, and so on) and
mainframe traffic.
A SAN can be used to bypass traditional network bottlenecks. It facilitates direct,
high speed data transfers between servers and storage devices, potentially in
any of the following three ways:
Server to storage: This is the traditional model of interaction with storage
devices. The advantage is that the same storage device may be accessed
serially or concurrently by multiple servers.
Server to server: A SAN may be used for high-speed, high-volume
communications between servers.
Storage to storage: This outboard data movement capability enables data to
be moved without server intervention, thereby freeing up server processor
cycles for other activities like application processing. Examples include a disk
device backing up its data to a tape device without server intervention, or
remote device mirroring across the SAN.
Why would you want one? SANs allow applications that move data to perform
better, for example, by having the data sent directly from source to target device
without any server intervention. SANs also enable new network architectures
where multiple hosts access multiple storage devices connected to the same
network. Using a SAN can potentially offer the following benefits:
Improvements to application availability: Storage is independent of
applications and accessible through multiple data paths for better reliability,
availability and serviceability.
Higher application performance: Storage processing off-loaded from servers
and moved onto a separate network.
Centralized and consolidated storage: Simpler management, scalability,
flexibility, and availability.
Data transfer and vaulting to remote sites: Remote copy of data enabled for
disaster protection and against malicious attack.
Simplified centralized management: Single image of storage media simplifies
management.Add text here (Body0).
4
IBM TotalStorage DS300 and DS400 Best Practices Guide