HP-UX Reference (11i v2 03/08) - 1M System Administration Commands A-M (vol 3)

l
lvsplit(1M) lvsplit(1M)
(Requires Optional HP MirrorDisk/UX Software)
NAME
lvsplit - split mirrored LVM logical volume into two logical volumes
SYNOPSIS
/usr/sbin/lvsplit
[-A autobackup ][-s suffix][
-g PhysicalVolumeGroup] lv_path ...
Remarks
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.
lvsplit cannot be performed if the volume group is activated in shared mode.
DESCRIPTION
The
lvsplit command splits a single- or double-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 as unmirrored or single-mirrored.
If the
-s option is specified, the new logical volume name has the form lv_path suffix.If
-s is not
specified, suffix defaults to
b,asinlv_path b.
If more than one lv_path is specified on the command line,
lvsplit ensures that all logical volumes are
brought offline together in one system call, ensuring predictable results among the logical volumes. Up to
127 logical volumes can be specified on the command line. All logical volumes must belong to the same
volume group, and there must be enough unused logical volumes remaining in the volume group to hold
the newly split logical volumes. A volume group can contain up to 255 logical volumes.
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.
Whenever a mirrored logical volume 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. When the two logical volumes are subsequently
merged using
lvmerge, the bit map is used to decide which areas of the logical volumes need to be
resynchronized (see lvmerge(1M)). This bit map remains in existence until the merge is completed, until
one of the logical volumes is extended, reduced, or split again, or until the system is rebooted.
The new logical volume must be checked with the
fsck command before it is mounted (see fsck(1M)).
lvsplit 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
lvmerge command (see lvmerge(1M)).
Options and Arguments
lvsplit recognizes the following options and arguments:
lv_path The block device path name of a logical volume. Up to 127 logical volumes in
the same volume group can be specified at one time.
-A autobackup Set automatic backup for invocation of this command. autobackup can have
one of the following values:
y Automatically back up configuration changes made to the logical volume.
This is the default.
After this command executes, the
vgcfgbackup command (see
vgcfgbackup (1M)) is executed for the volume group to which the logical
volume belongs.
n Do not back up configuration changes this time.
-g PhysicalVolumeGroup
The offline logical volumes will be created using the mirror copies on the phy-
sical volumes in the specified PhysicalVolumeGroup.
-s suffix Specify the suffix to use to identify the new logical volume. The new logical
volume name has the form lv_pathsuffix.If-s is omitted, suffix defaults to b,
as in lv_path b.
HP-UX 11i Version 2: August 2003 − 1 − Hewlett-Packard Company Section 1M−−411