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.
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.
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:
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 ...