54 Netra 440 Server System Administration Guide • August 2004
RAID Technology
VERITAS Volume Manager and Solstice DiskSuite™ software support RAID
technology to optimize performance, availability, and cost per user. RAID
technology reduces recovery time in the event of file system errors, and increases
data availability even in the event of a disk failure. There are several levels of RAID
configurations that provide varying degrees of data availability with corresponding
trade-offs in performance and cost.
This section describes some of the most popular and useful of those configurations,
including:
■ Disk concatenation
■ Disk striping (RAID 0)
■ Disk mirroring (RAID 1)
■ Disk striping with parity (RAID 5)
■ Hot-spares
Disk Concatenation
Disk concatenation is a method for increasing logical volume size beyond the
capacity of one hard drive by creating one large volume from two or more smaller
drives. This lets you create arbitrarily large partitions.
FIGURE 3-1 Graphical Representation of Disk Concatenation
Using this method, the concatenated disks are filled with data sequentially, with the
second disk being written to when no space remains on the first, the third when no
space remains on the second, and so on.
