Kbase P85907: Considerations about SAN (Storage Area Network)
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
17/12/2004 |
|
Status: Verified
GOAL:
Considerations about SAN (Storage Area Network)
GOAL:
What should I consider for using SAN (Storage Area Network)?
FIX:
The differences are blurring somewhat as time progresses and vary considerably from vendor to vendor, but they are still two different classes of storage products.
The important differences are:
0. Type of I/O interface and network
SAN typically has a dedicated I/O network that requires special host adapters. Often it is using Fibre-Channel Arbotrated Loops. Each machine that is connected to the SAN requires a FC adapter and special device drivers.
Most NAS boxes rely on NFS or CIFS protocols for file-sharing and can be used on a regular LAN, sharing it with other network traffic. For some usage scenarios that is fine, and for others a dedicated high speed network like Gigabit Ethernet can (and should) be used for the I/O traffic.
1. Price-points
With both, you can pay more or less, and the more you pay, the more you can get.
On average, SAN's cost more than NAS, partly because the interface hardware is different, and partly because the target markets are different. SAN's are typically aimed more at high-end systems with greater reliability and higher capacity, flexibility and management requirements.
Some NAS boxes, like the Snap Server 1100, are inexpensive and aimed at home and small office usage with fairly light duty requirements. Others are intended for use with servers, and cost more.
2. Performance
SAN's usually provide higher performance than NAS's. But this varies a lot from one vendor to another.