Installation guide

Figure 8–3 illustrates the three types of LSM disks: simple, sliced, and
nopriv. You can add all of these types of disks into an LSM disk group.
Figure 8–3: Types of LSM Disks
LSM Simple Disk
LSM Sliced Disk
LSM nopriv Disk
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ZK−1010U−AI
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In Figure 8–3:
• Simple disks have both public and private regions in the same partition
(rz3g).
• Sliced disks use the entire disk ( rz7) and use the disk label on a disk
to identify the private (rz7h) and the public (rz7g) regions.
• Nopriv disks have no private region, and so they do not contain LSM
configuration information. Therefore, you can add nopriv disks only to
an existing disk group that includes a simple disk or a sliced disk.
LSM configuration databases are stored on the private region of each LSM
disk except the nopriv disk. The public regions of the LSM disks
collectively form the storage space for application use. For purposes of
availability, each simple and sliced disk contains two copies of the
configuration database. A sliced disk takes up the entire physical disk, but
simple and nopriv disks can reside on the same physical disk. The disk
label tags identify the partitions to LSM as LSM disks.
8.2.3 Naming LSM Disks
When you perform disk operations, you should understand the disk-naming
conventions for a disk access name and disk media name. Disk access
names and disk media names are treated internally as two types of LSM
disk objects. Some operations require that you specify the disk access
name, while others require the disk media name.
The following definitions describe these disk-naming conventions:
• Disk access name (also referred to as devname or device name)
The device name or address used to access a physical disk. A disk
access name is of the form:
Administering the Logical Storage Manager 8–7