Purpose
Splits a single mirror copy of
a fully mirrored volume group.
Syntax
splitvg [ -y SnapVGname ] [ -c Copy ] [ -f ] [ -i ] VGname
Description
The
splitvg command
splits a single mirror copy of a fully mirrored volume group into
a snapshot volume group. The original volume group
VGname will
stop using the disks that are now part of the snapshot volume group
SnapVGname.
Both volume groups will keep track of the writes within the volume
group so that when the snapshot volume group is rejoined with the
original volume group consistent data is maintained across the rejoined
mirrors copies.
Note: - To split a volume group, all logical volumes in the volume group
must have the target mirror copy and the mirror must exist on a disk
or set of disks. Only the target mirror copy must exist on the target
disk or disks.
- The splitvg command will fail if any of the disks to be
split are not active within the original volume group.
- In the unlikely event of a system crash or loss of quorum while
running this command, the joinvg command must be run to rejoin
the disks back to the original volume group.
- New logical volumes and file system mount points will be created
in the snapshot volume group.
- The splitvg command is not supported for the rootvg.
- The splitvg command is not supported for a volume group
that has an active paging space.
- When the splitvg command targets a concurrent-capable volume
group which is varied on in non-concurrent mode, the new volume group
that is created will not be varied on when the splitvg command
completes. The new volume group must be varied on manually.
Flags
| Item |
Description |
|---|
| -y SnapVGname |
Allows the volume group
name to be specified rather than having the name generated automatically.
Volume group names must be unique across the system and can range
from 1 to 15 characters. The name cannot begin with a prefix already
defined in the PdDv class in the Device Configuration database
for other devices. The new volume group name is sent to standard output. |
| -c Copy |
Which mirror to split.
Valid values are 1, 2, or 3. The default is the second copy. |
| -f |
Will force the split even
if the mirror copy specified to create the snapshot volume group has
stale partitions. |
| -i |
Will split the mirror
copy of a volume group into a new volume group that can not be rejoined
into the original. |
Security
Access Control: You must have root authority
to run this command.
Examples
- To split a volume group, enter:
splitvg testvg
The
second mirror copy of the volume group testvg is split into
new volume group with an automatically generated name, which will
be displayed.
- To split first mirror copy of the volume group with the name snapvg,
enter:
splitvg -y snapvg -c 1 testvg
Files
| Item |
Description |
|---|
| /usr/sbin |
Directory where the splitvg command resides. |