lvsplit(1M) lvsplit(1M)
NAME
lvsplit - split mirrored LVM logical volume into two logical volumes
SYNOPSIS
autobackup] suffix] PhysicalVolumeGroup] lv_path ...
Remarks
If the logical volume input arguments belong to a combination of volume groups version 1.0 and 2.0 or higher, the arguments might not be
processed in the order they are listed on the command line.
This command requires the installation of the optional HP MirrorDisk/UX software (not included in the standard HP-UX operating system)
before it can be used.
DESCRIPTION
The command splits a mirrored logical volume, lv_path, into two logical volumes. A second logical volume is created containing one copy of
the data. The original logical volume is appropriately reset to have one fewer mirror copies.
If the option is specified, the new logical volume name has the form lv_pathsuffix. If is not specified, suffix defaults to as in
If more than one lv_path is specified on the command line, ensures that all logical volumes are brought offline together in one system
call, ensuring predictable results among the logical volumes. All logical volumes must belong to the same volume group. The current num-
ber of logical volumes in the volume group added to the number of logical volumes specified on the command line must not exceed the maximum
number of logical volumes allowed in the volume group.
If PhysicalVolumeGroup is specified, the offline logical volumes are created using the mirror copies on the physical volumes contained in
the specified physical volume group.
When a mirrored logical volume of a non-shared volume group is split into two logical volumes, a bit map is stored that keeps track of all
writes to either logical volume in the split pair. If the volume group is shared, this bit map is not created. When the two logical vol-
umes are subsequently merged using the bit map, if present, is used to decide which areas of the logical volumes need to be resynchronized
(see lvmerge(1M)). This bit map remains in existence until one of the following conditions occurs:
o The merge is completed.
o One of the logical volumes is extended, reduced, or split again.
o The volume group is cross-activated to shared mode (see vgchange(1M)).
o The system is rebooted.
The new logical volume must be checked with the command before it is mounted (see fsck(1M)). flushes the file system to a consistent state
except for pipes and unlinked but open files.
To rejoin two split copies of a logical volume, use the command (see lvmerge(1M)).
Options and Arguments
recognizes the following options and arguments:
lv_path The block device path name of a logical volume. Multiple logical volumes in the same volume group can be speci-
fied. The current number of logical volumes in the volume group added to the number of logical volumes speci-
fied on the command line must not exceed the maximum number of logical volumes allowed in the volume group.
Set automatic backup for invocation of this command.
autobackup can have one of the following values:
Automatically back up configuration changes made to the logical volume.
This is the default.
After this command executes, the command (see vgcfgbackup(1M)) is executed for the volume group to which
the logical volume belongs.
Do not back up configuration changes this time.
The offline logical volumes will be created using the mirror copies
on the physical volumes in the specified PhysicalVolumeGroup.
Specify the suffix to use to identify the new logical volume.
The new logical volume name has the form lv_pathsuffix. If is omitted, suffix defaults to as in
Shared Volume Group Considerations
For volume group version 1.0 and 2.0, cannot be used if the volume group is activated in shared mode. For volume groups version 2.1 (or
higher), can be performed when activated in either shared, exclusive, or standalone mode.
Note that the daemon must be running on all the nodes sharing a volume group activated in shared mode. See lvmpud(1M).
When is issued, it creates the new logical volume device special files on all the nodes sharing the volume group. The device special files
are created with the same name on the nodes sharing the volume group.
When a node wants to share the volume group, the user must first execute a if logical volumes were split at the time the volume group was
not activated on that node.
The logical volumes device special files should have the same name on all the nodes sharing the volume group.
LVM shared mode is currently only available in Serviceguard clusters.
EXTERNAL INFLUENCES
Environment Variables
determines the language in which messages are displayed.
If is not specified or is null, it defaults to "C" (see lang(5)).
If any internationalization variable contains an invalid setting, all internationalization variables default to "C" (see environ(5)).
EXAMPLES
Split the mirrored logical volume into two copies. Call the new logical volume
Split the mirrored logical volume into two copies. The offline logical volume will be created using the mirror copy on the physical vol-
umes contained in the physical volume group
Split an online logical volume which is currently mounted on so that a backup can take place:
Perform a backup operation, then:
Split two logical volumes at the same time:
Perform a backup operation on the split logical volumes, then rejoin them:
SEE ALSO
lvcreate(1M), lvextend(1M), lvmerge(1M), lvmpud(1M).
Requires Optional HP MirrorDisk/UX Software lvsplit(1M)