Red Hat GLOBAL FILE SYSTEM 5.0, Руководство администратора

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LVM Troubleshooting
This chapter provide instructions for troubleshooting a variety of LVM issues.
1. Troubleshooting Diagnostics
If a command is not working as expected, you can gather diagnostics in the following ways:
• Use the
-v
,
-vv
,
-vvv
, or
-vvvv
argument of any command for increasingly verbose levels of
output.
• If the problem is related to the logical volume activation, set 'activation = 1' in the 'log' section
of the configuration file and run the command with the
-vvvv
argument. After you have
finished examining this output be sure to reset this parameter to 0, to avoid possible problems
with the machine locking during low memory situations.
• Run the
lvmdump
command, which provides and information dump for diagnostic purposes.
For information, see the
lvmdump
(8) man page.
• Execute the
lvs -v
,
pvs -a
or
dmsetup info -c
command for additional system
information.
• Examine the last backup of the metadata in the
/etc/lvm/backup
file and archived versions
in the
/etc/lvm/archive
file.
• Check the current configuration information by running the
lvm dumpconfig
command.
• Check the
.cache
file in the
/etc/lvm
directory for a record of which devices have physical
volumes on them.
2. Displaying Information on Failed Devices
You can use the
-P
argument of the
lvs
or
vgs
command to display information about a failed
volume that would otherwise not appear in the output. This argument permits some operations
even though the metatdata is not completely consistent internally. For example, if one of the
devices that made up the volume group
vg
failed, the
vgs
command might show the following
output.
[root@link-07 tmp]# vgs -o +devices
Volume group "vg" not found
If you specify the
-P
argument of the
vgs
command, the volume group is still unusable but you
can see more information about the failed device.
[root@link-07 tmp]# vgs -P -o +devices
Chapter 6.
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