Novell LINUX ENTERPRISE SERVER 11 - DEPLOYMENT, Руководство по развертыванию

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table of a hard disk when any partition on this disk is in use. However, if you already
have a functioning LVM configuration on your system, physical repartitioning should
not be necessary. Instead, change the configuration of the logical volumes.
At the beginning of the physical volumes (PVs), information about the volume is written
to the partition. To reuse such a partition for other non-LVM purposes, it is advisable
to delete the beginning of this volume. For example, in the VG
system
and PV
/dev/
sda2
, do this with the command
dd if=/dev/zero of=/dev/sda2 bs=512
count=1
.
WARNING: File System for Booting
The file system used for booting (the root file system or
/boot
) must not be
stored on an LVM logical volume. Instead, store it on a normal physical partition.
For more details about LVM, see the Storage Administration Guide.
15.2 LVM Configuration
This section briefly describes the principles behind the Logical Volume Manager (LVM)
and its basic features that make it useful under many circumstances. In
Section 15.2.2,
“LVM Configuration with YaST” (page 237), learn how to set up LVM with YaST.
WARNING
Using LVM might be associated with increased risk, such as data loss. Risks also
include application crashes, power failures, and faulty commands. Save your
data before implementing LVM or reconfiguring volumes. Never work without
a backup.
15.2.1 The Logical Volume Manager
The LVM enables flexible distribution of hard disk space over several file systems. It
was developed because sometimes the need to change the segmentation of hard disk
space arises only after the initial partitioning during installation has already been done.
Because it is difficult to modify partitions on a running system, LVM provides a virtual
pool (volume group, VG for short) of memory space from which logical volumes (LVs)
Advanced Disk Setup 235