Provided by: lvm2_2.02.133-1ubuntu10_amd64 
NAME
vgchange — change attributes of a volume group
SYNOPSIS
vgchange [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-a|--activate
[a|e|s|l] {y|n}] [--activationmode {complete|degraded|partial}]
[-K|--ignoreactivationskip] [--monitor {y|n}] [--poll {y|n}] [-c|--clustered {y|n}]
[-u|--uuid] [--commandprofile ProfileName] [-d|--debug] [--deltag Tag] [--detachprofile]
[-h|--help] [--ignorelockingfailure] [--ignoremonitoring] [--ignoreskippedcluster]
[--sysinit] [--noudevsync] [--lock-start] [--lock-stop] [--lock-type LockType]
[-l|--logicalvolume MaxLogicalVolumes] [-p|--maxphysicalvolumes MaxPhysicalVolumes]
[--metadataprofile ProfileName] [--[vg]metadatacopies] NumberOfCopies|unmanaged|all]
[-P|--partial] [-s|--physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]] [-S|--select
Selection] [--systemid SystemID] [--refresh] [-t|--test] [-v|--verbose] [--version]
[-x|--resizeable {y|n}] [VolumeGroupName...]
DESCRIPTION
vgchange allows you to change the attributes of one or more volume groups. Its main
purpose is to activate and deactivate VolumeGroupName, or all volume groups if none is
specified. Only active volume groups are subject to changes and allow access to their
logical volumes. [Not yet implemented: During volume group activation, if vgchange
recognizes snapshot logical volumes which were dropped because they ran out of space, it
displays a message informing the administrator that such snapshots should be removed (see
lvremove(8)). ]
OPTIONS
See lvm(8) for common options.
-A, --autobackup {y|n}
Controls automatic backup of metadata after the change. See vgcfgbackup(8).
Default is yes.
-a, --activate [a|e|s|l]{y|n}
Controls the availability of the logical volumes in the volume group for
input/output. In other words, makes the logical volumes known/unknown to the
kernel. If autoactivation option is used (-aay), each logical volume in the volume
group is activated only if it matches an item in the
activation/auto_activation_volume_list set in lvm.conf. If this list is not set,
then all volumes are considered for activation. The -aay option should be also
used during system boot so it's possible to select which volumes to activate using
the activation/auto_activation_volume_list settting.
Activation of a logical volume creates a symbolic link
/dev/VolumeGroupName/LogicalVolumeName pointing to the device node. This link is
removed on deactivation. All software and scripts should access the device through
this symbolic link and present this as the name of the device. The location and
name of the underlying device node may depend on the distribution and configuration
(e.g. udev) and might change from release to release.
In a clustered VG, clvmd is used for activation, and the following options are
possible:
With -aey, clvmd activates the LV in exclusive mode (with an exclusive lock),
allowing a single node to activate the LV.
With -asy, clvmd activates the LV in shared mode (with a shared lock), allowing
multiple nodes to activate the LV concurrently. If the LV type prohibits shared
access, such as an LV with a snapshot, the 's' option is ignored and an exclusive
lock is used.
With -ay (no mode specified), clvmd activates the LV in shared mode if the LV type
allows concurrent access, such as a linear LV. Otherwise, clvmd activates the LV
in exclusive mode.
With -aey, -asy, and -ay, clvmd attempts to activate the LV on all nodes. If
exclusive mode is used, then only one of the nodes will be successful.
With -an, clvmd attempts to deactivate the LV on all nodes.
With -aly, clvmd activates the LV only on the local node, and -aln deactivates only
on the local node. If the LV type allows concurrent access, then shared mode is
used, otherwise exclusive.
LVs with snapshots are always activated exclusively because they can only be used
on one node at once.
For local VGs, -ay, -aey, and -asy are all equivalent.
In a shared VG, lvmlockd is used for locking, and the following options are
possible:
With -aey, the command activates the LV in exclusive mode, allowing a single host
to activate the LV (the host running the command). Before activating the LV, the
command uses lvmlockd to acquire an exclusive lock on the LV. If the lock cannot
be acquired, the LV is not activated and an error is reported. This would happen
if the LV is active on another host.
With -asy, the command activates the LV in shared mode, allowing multiple hosts to
activate the LV concurrently. Before activating the LV, the command uses lvmlockd
to acquire a shared lock on the LV. If the lock cannot be acquired, the LV is not
activated and an error is reported. This would happen if the LV is active
exclusively on another host. If the LV type prohibits shared access, such as a
snapshot, the command will report an error and fail.
With -an, the command deactivates the LV on the host running the command. After
deactivating the LV, the command uses lvmlockd to release the current lock on the
LV.
With lvmlockd, an unspecified mode is always exclusive, -ay defaults to -aey.
--activationmode {complete|degraded|partial}
The activation mode determines whether logical volumes are allowed to activate when
there are physical volumes missing (e.g. due to a device failure). complete is the
most restrictive; allowing only those logical volumes to be activated that are not
affected by the missing PVs. degraded allows RAID logical volumes to be activated
even if they have PVs missing. (Note that the "mirror" segment type is not
considered a RAID logical volume. The "raid1" segment type should be used
instead.) Finally, partial allows any logical volume to be activated even if
portions are missing due to a missing or failed PV. This last option should only
be used when performing recovery or repair operations. degraded is the default
mode. To change it, modify activation_mode in lvm.conf(5).
-K, --ignoreactivationskip
Ignore the flag to skip Logical Volumes during activation.
-c, --clustered {y|n}
If clustered locking is enabled, this indicates whether this Volume Group is shared
with other nodes in the cluster or whether it contains only local disks that are
not visible on the other nodes. If the cluster infrastructure is unavailable on a
particular node at a particular time, you may still be able to use Volume Groups
that are not marked as clustered.
--detachprofile
Detach any metadata configuration profiles attached to given Volume Groups. See
lvm.conf(5) for more information about metadata profiles.
-u, --uuid
Generate new random UUID for specified Volume Groups.
--monitor {y|n}
Start or stop monitoring a mirrored or snapshot logical volume with dmeventd, if it
is installed. If a device used by a monitored mirror reports an I/O error, the
failure is handled according to mirror_image_fault_policy and
mirror_log_fault_policy set in lvm.conf(5).
--poll {y|n}
Without polling a logical volume's backgrounded transformation process will never
complete. If there is an incomplete pvmove or lvconvert (for example, on rebooting
after a crash), use --poll y to restart the process from its last checkpoint.
However, it may not be appropriate to immediately poll a logical volume when it is
activated, use --poll n to defer and then --poll y to restart the process.
--sysinit
Indicates that vgchange(8) is being invoked from early system initialisation
scripts (e.g. rc.sysinit or an initrd), before writeable filesystems are available.
As such, some functionality needs to be disabled and this option acts as a shortcut
which selects an appropriate set of options. Currently this is equivalent to using
--ignorelockingfailure, --ignoremonitoring, --poll n and setting
LVM_SUPPRESS_LOCKING_FAILURE_MESSAGES environment variable.
If --sysinit is used in conjunction with lvmetad(8) enabled and running,
autoactivation is preferred over manual activation via direct vgchange call.
Logical volumes are autoactivated according to auto_activation_volume_list set in
lvm.conf(5).
--noudevsync
Disable udev synchronisation. The process will not wait for notification from udev.
It will continue irrespective of any possible udev processing in the background.
You should only use this if udev is not running or has rules that ignore the
devices LVM2 creates.
--ignoremonitoring
Make no attempt to interact with dmeventd unless --monitor is specified. Do not
use this if dmeventd is already monitoring a device.
--lock-start
Start the lockspace of a shared VG in lvmlockd. lvmlockd locks becomes available
for the VG, allowing LVM to use the VG. See lvmlockd(8).
--lock-stop
Stop the lockspace of a shared VG in lvmlockd. lvmlockd locks become unavailable
for the VG, preventing LVM from using the VG. See lvmlockd(8).
--lock-type LockType
Change the VG lock type to or from a shared lock type used with lvmlockd. See
lvmlockd(8).
-l, --logicalvolume MaxLogicalVolumes
Changes the maximum logical volume number of an existing inactive volume group.
-p, --maxphysicalvolumes MaxPhysicalVolumes
Changes the maximum number of physical volumes that can belong to this volume
group. For volume groups with metadata in lvm1 format, the limit is 255. If the
metadata uses lvm2 format, the value 0 removes this restriction: there is then no
limit. If you have a large number of physical volumes in a volume group with
metadata in lvm2 format, for tool performance reasons, you should consider some use
of --pvmetadatacopies 0 as described in pvcreate(8), and/or use --vgmetadatacopies.
--metadataprofile ProfileName
Uses and attaches ProfileName configuration profile to the volume group metadata.
Whenever the volume group is processed next time, the profile is automatically
applied. The profile is inherited by all logical volumes in the volume group unless
the logical volume itself has its own profile attached. See lvm.conf(5) for more
information about metadata profiles.
--[vg]metadatacopies NumberOfCopies|unmanaged|all
Sets the desired number of metadata copies in the volume group. If set to a non-
zero value, LVM will automatically manage the 'metadataignore' flags on the
physical volumes (see pvchange or pvcreate --metadataignore) in order to achieve
NumberOfCopies copies of metadata. If set to unmanaged, LVM will not automatically
manage the 'metadataignore' flags. If set to all, LVM will first clear all of the
'metadataignore' flags on all metadata areas in the volume group, then set the
value to unmanaged. The vgmetadatacopies option is useful for volume groups
containing large numbers of physical volumes with metadata as it may be used to
minimize metadata read and write overhead.
-s, --physicalextentsize PhysicalExtentSize[BbBsSkKmMgGtTpPeE]
Changes the physical extent size on physical volumes of this volume group. A size
suffix (k for kilobytes up to t for terabytes) is optional, megabytes is the
default if no suffix is present. For LVM2 format, the value must be a power of 2
of at least 1 sector (where the sector size is the largest sector size of the PVs
currently used in the VG) or, if not a power of 2, at least 128KiB. For the older
LVM1 format, it must be a power of 2 of at least 8KiB. The default is 4 MiB.
Before increasing the physical extent size, you might need to use lvresize,
pvresize and/or pvmove so that everything fits. For example, every contiguous
range of extents used in a logical volume must start and end on an extent boundary.
If the volume group metadata uses lvm1 format, extents can vary in size from 8KiB
to 16GiB and there is a limit of 65534 extents in each logical volume. The default
of 4 MiB leads to a maximum logical volume size of around 256GiB.
If the volume group metadata uses lvm2 format those restrictions do not apply, but
having a large number of extents will slow down the tools but have no impact on I/O
performance to the logical volume. The smallest PE is 1KiB.
The 2.4 kernel has a limitation of 2TiB per block device.
--systemid SystemID
Changes the system ID of the VG. Using this option requires caution because the VG
may become foreign to the host running the command, leaving the host unable to
access it. See lvmsystemid(7).
--refresh
If any logical volume in the volume group is active, reload its metadata. This is
not necessary in normal operation, but may be useful if something has gone wrong or
if you're doing clustering manually without a clustered lock manager.
-x, --resizeable {y|n}
Enables or disables the extension/reduction of this volume group with/by physical
volumes.
Examples
To activate all known volume groups in the system:
vgchange -a y
To change the maximum number of logical volumes of inactive volume group vg00 to 128.
vgchange -l 128 /dev/vg00
SEE ALSO
lvchange(8), lvm(8), vgcreate(8)