Installation guide

Figure 8–1: LSM Disk Storage Management
vol01
vol02
vol03
Database
File System
Application
ZK−1011U−R
Block− and Character−
Device Interface
On a system that does not have LSM installed, I/O activity from the UNIX
system kernel is passed through disk device drivers that control the flow of
data to and from disks. When LSM is installed, the I/O passes from the
kernel to the LSM volume device driver, then to the disk device drivers.
The LSM software maps the logical configuration of the system to the
physical disk configuration. This is done transparently to the file systems,
databases, and applications above it because LSM supports the standard
block device and character device interfaces to store and retrieve data on
LSM volumes. Thus, you do not have to change applications to access data
on LSM volumes.
The block device special files associated with LSM volumes exist in the
/dev/vol directory and the character device special files associated with
LSM volumes exist in the /dev/svol directory.
8.2.1 LSM Objects
LSM logically binds together the disk devices into a volume that represents
the disks as a single virtual device to applications and users. LSM uses a
Administering the Logical Storage Manager 8–3