好文推荐：使用SAN的20个benefits。
The benefits of using a SAN are many because a SAN usually has a very high return on investment (ROI), makes the total cost of ownership (TCO) of computing less, and has a pay-back period (PBP) based in months instead of years. Following is a list of many of the ways that you can expect a SAN to be beneficial.
1. Removes the distance limits of SCSI-connected disks: The maximum length of a SCSI bus is around 25 meters. Fibre Channel SANs allow you to connect your disks to your servers over much greater distances.
2. Greater performance: Fibre Channel SANs allow connection to disks at up to 200 megabytes per second today, with speeds of up to 1 gigabyte per second in the near future.
3. Increased disk utilization: SAN enables more than one server to access the same physical disk, which lets you allocate the free space on those disks more effectively.
4. Higher availability to storage by use of multiple access paths: A SAN allows for multiple physical connections to disks from a single or multiple servers.
5. Deferred disk procurement: Because you can use disk space more effectively, no space goes to waste, thus you don’t need to buy disks as often as you used to.
6. Reduced data center rack/floor space: Because you don’t need to buy big servers with room for lots of disks, you can buy fewer, smaller servers, which takes up less room.
7. New disaster recovery capabilities: This is a major benefit. SAN devices have the ability to mirror the data on the disks to another location. This can make your data safe if a disaster occurs.
8. Online recovery: By using online mirrors of your data in a SAN device, you can instantly recover your data if it becomes corrupt.
9. Better staff utilization: SANs enable fewer people to manage much more data.
10. Reduction of management costs as a percent of storage costs: Because you need fewer people, your management costs go down.
11. Improved overall availability: This is another big one. SAN storage is much more reliable than internal, server-based disk storage. Things break a lot less often.
12. Reduction of servers: You won’t need as many file servers with a SAN. And because SANs are so fast, if you connect your current servers to the SAN, they run faster. This lets you get more out of your current servers so that you don’t need to buy new servers as often.
13. Improved network performance and fewer network upgrades: A SAN lets you back up all your data over a storage network rather than a LAN. Therefore, less room is needed on the LAN, so you can get more out of it.
14. Increased input/output (I/O) performance and bulk data movement: Yup, SANs are fast. They move data much faster than do internal drives or devices attached to the LAN.
15. Reduced/eliminated backup windows: A backup window is the window of time that you have to back up all your data. Because backup can be done over the SAN instead of over the LAN, you can back up any time, day or night.
16. Protected critical data: SAN storage devices use technology to ensure that your critical data remains safe and available.
17. Nondisruptive scalability: You can add storage to a storage network at any time without affecting the devices currently using the network.
18. Easier applications development and testing: By using SAN-based mirror copies of production data, you can easily use actual production data to test new applications while the original application stays online.
19. Supported server clustering: Server clustering is a method of making two individual servers look like one. If one has a heart attack, the other one takes over automatically to keep the applications running. Clusters require access to a shared disk drive. A SAN makes this possible.
20. Storage on demand: Because SAN disks are available to any server in the storage network, free storage space can be allocated on demand to any server that needs it, any time.