Using SANs and NAS

Chapter 3. Managing a SAN

What’s it like to manage a SAN? What kind of applications lend themselves to SANs? What kind of tasks do you find yourself performing once you’ve decided to actually purchase a SAN? Why does a SAN require more management than traditional, parallel SCSI? What can you do with a SAN that you can’t do without a SAN? These are all important questions.

The Different Uses for SANs

Many of the reasons you would want to use a SAN are the same as the reasons for using NAS. Those reasons are covered primarily in Chapter 1. Chapter 6 covers the applications where NAS systems perform exceptionally well. Therefore, this section of this chapter covers only the applications in which SANs tend to perform better than NAS.

Large, High-Performance Databases

SANs perform well with large, high-performance databases. While some databases support placing their datafiles on a NAS filer, many don’t. Even if the database doesn’t specifically support NAS, there may be performance issues with running a large, high-performance database on NAS. Therefore, many environments chose to run their databases on SAN-attached disks. SAN-attached disks offer two distinct advantages to NAS filers:

High-performance backups

When you talk about terabyte-sized databases, it’s hard to beat the backup and recovery performance of SAN-attached disks, especially if you start talking about server- or client-free backups. Such backups allow you to back up a large amount of data in a short period of time, without ...