Managing Systems and Workgroups: A Guide for HP-UX System Administrators

Administering a System: Managing Disks and Files
Managing Disks
Chapter 6594
• “Removing a Logical Volume” on page 870
• “Adding a Mirror to an Existing Logical Volume” on page 870
• “Removing a Mirror from a Logical Volume” on page 872
• “Moving a Directory to a Logical Volume on Another System” on
page 874
LVM Troubleshooting
If You Can’t Boot From a Logical Volume
If you cannot boot from a logical volume, a number of things might be
responsible for this situation. In addition to the same kinds of problems
associated with boots from non-LVM disks, any of the following could
cause an LVM-based system not to boot:
• With LVM disks, there are pointers to the root file system, primary
swap area, and dump area located within the BDRA at the beginning
of each bootable LVM disk, along with information about the size of
each of these areas. These LVM pointers may have become corrupted,
not current, or just no longer present. Because of the importance of
maintaining up-to-date information within the BDRA, remember to
use the lvrmboot and/or lvlnboot commands whenever you make a
change that affects the location of the root, boot, primary swap, or
dump logical volumes.
• The system thinks it is trying to configure a root, swap, or dump area
on a logical volume, but the disk it is attempting to use is not an LVM
disk.
• The system tries to boot from a disk partition that has LVM
information on it.
• Not enough disks are present in the root volume group to make a
quorum. At boot time, you will see a message indicating that not
enough physical volumes are available.
The first and last of these items will now be discussed in further detail.
Booting When LVM Data Structures Are Lost When critical LVM
data structures have been lost, you will need to use the recovery portion
of the Support Media included in the HP-UX product kit to restore the
corrupted disk image from your backup tape. For more information, see
Appendix B of the Support Media User’s Manual.