Red Hat GLOBAL FILE SYSTEM 5.0, Руководство администратора

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3.9. Splitting a Volume Group
To split the physical volumes of a volume group and create a new volume group, use the
vgsplit
command.
Logical volumes cannot be split between volume groups. Each existing logical volume must be
entirely on the physical volumes forming either the old or the new volume group. If necessary,
however, you can use the
pvmove
command to force the split.
The following example splits off the new volume group
smallvg
from the original volume group
bigvg
.
# vgsplit bigvg smallvg /dev/ram15
Volume group "smallvg" successfully split from "bigvg"
3.10. Combining Volume Groups
Two combine two volume groups into a single volume group, use the
vgmerge
command. You
can merge an inactive "source" volume with an active or an inactive "destination" volume if the
physical extent sizes of the volume are equal and the physical and logical volume summaries of
both volume groups fit into the destination volume groups limits.
The following command merges the inactive volume group
my_vg
into the active or inactive
volume group
databases
giving verbose runtime information.
vgmerge -v databases my_vg
3.11. Backing Up Volume Group Metadata
Metadata backups and archives are automatically created on every volume group and logical
volume configuration change unless disabled in the
lvm.conf
file. By default, the metadata
backup is stored in the
/etc/lvm/backup
file and the metadata archives are stored in the
/etc/lvm/archives
file. You can manually back up the metadata to the
/etc/lvm/backup
file
with the
vgcfgbackup
command.
The
vgcfrestore
command restores the metadata of a volume group from the archive to all the
physical volumes in the volume groups.
For an example of using the
vgcfgrestore
command to recover physical volume metadata,
see Section 4, “Recovering Physical Volume Metadata” .
3.12. Renaming a Volume Group
Use the
vgrename
command to rename an existing volume group.
Either of the following commands renames the existing volume group
vg02
to
my_volume_group
Combining Volume Groups
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