Managing Serviceguard 13th Edition, February 2007

Understanding Serviceguard Software Components
Volume Managers for Data Storage
Chapter 3 119
Examples of Storage on Disk Arrays
Figure 3-23 shows an illustration of storage configured on a disk array.
Physical disks are configured by an array utility program into logical
units or LUNs which are then seen by the operating system.
Figure 3-23 Physical Disks Combined into LUNs
NOTE LUN definition is normally done using utility programs provided by the
disk array manufacturer. Since arrays vary considerably, you should
refer to the documentation that accompanies your storage unit.
Figure 3-24 shows LUNs configured with multiple paths (links) to
provide redundant pathways to the data.
NOTE Under agile addressing, the storage units in these example would have
names such as disk1, disk2, disk3, etc. See “About Device File Names
(Device Special Files)” on page 115.