Ubuntu Manpage: lvchange — Change the attributes of logical volume(s)

Provided by: lvm2_2.03.16-3ubuntu3.2_amd64

NAME

       lvchange — Change the attributes of logical volume(s)

SYNOPSIS

       lvchange option_args position_args
           [ option_args ]

        -a|--activate y|n|ay
           --activationmode partial|degraded|complete
           --addtag Tag
           --alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit
        -A|--autobackup y|n
           --cachemode writethrough|writeback|passthrough
           --cachepolicy String
           --cachesettings String
           --commandprofile String
           --compression y|n
           --config String
        -C|--contiguous y|n
        -d|--debug
           --deduplication y|n
           --deltag Tag
           --detachprofile
           --devices PV
           --devicesfile String
           --discards passdown|nopassdown|ignore
           --driverloaded y|n
           --errorwhenfull y|n
        -f|--force
        -h|--help
        -K|--ignoreactivationskip
           --ignorelockingfailure
           --ignoremonitoring
           --journal String
           --lockopt String
           --longhelp
        -j|--major Number
           --[raid]maxrecoveryrate Size[k|UNIT]
           --metadataprofile String
           --minor Number
           --[raid]minrecoveryrate Size[k|UNIT]
           --monitor y|n
           --nohints
           --nolocking
           --noudevsync
        -P|--partial
        -p|--permission rw|r
        -M|--persistent y|n
           --poll y|n
           --profile String
        -q|--quiet
        -r|--readahead auto|none|Number
           --readonly
           --rebuild PV
           --refresh
           --reportformat basic|json
           --resync
        -S|--select String
        -k|--setactivationskip y|n
           --setautoactivation y|n
           --[raid]syncaction check|repair
           --sysinit
        -t|--test
           --vdosettings String
        -v|--verbose
           --version
           --[raid]writebehind Number
           --[raid]writemostly PV[:t|n|y]
        -y|--yes
        -Z|--zero y|n

DESCRIPTION

       lvchange  changes LV attributes in the VG, changes LV activation in the kernel, and includes other utili‐
       ties for LV maintenance.

USAGE

       Change a general LV attribute.
       For options listed in parentheses, any one is
       required, after which the others are optional.

       lvchange
           ( -C|--contiguous y|n
             -p|--permission rw|r
             -r|--readahead auto|none|Number
             -k|--setactivationskip y|n
             -Z|--zero y|n
             -M|--persistent n
                --addtag Tag
                --deltag Tag
                --alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit
                --compression y|n
                --deduplication y|n
                --detachprofile
                --metadataprofile String
                --profile String
                --setautoactivation y|n
                --errorwhenfull y|n
                --discards passdown|nopassdown|ignore
                --cachemode writethrough|writeback|passthrough
                --cachepolicy String
                --cachesettings String
                --[raid]minrecoveryrate Size[k|UNIT]
                --[raid]maxrecoveryrate Size[k|UNIT]
                --vdosettings String
                --[raid]writebehind Number
                --[raid]writemostly PV[:t|n|y] )
            VG|LV|Tag|Select ...
           [ -a|--activate y|n|ay ]
           [    --poll y|n ]
           [    --monitor y|n ]
           [ COMMON_OPTIONS ]

       —

       Resyncronize a mirror or raid LV.
       Use to reset 'R' attribute on a not initially synchronized LV.

       lvchange --resync VG|LV1|Tag|Select ...
           [ -a|--activate y|n|ay ]
           [ COMMON_OPTIONS ]

           LV1 types: mirror raid

       —

       Resynchronize or check a raid LV.

       lvchange --syncaction check|repair VG|LV1|Tag|Select ...
           [ COMMON_OPTIONS ]

           LV1 types: raid

       —

       Reconstruct data on specific PVs of a raid LV.

       lvchange --rebuild PV VG|LV1|Tag|Select ...
           [ COMMON_OPTIONS ]

           LV1 types: raid

       —

       Activate or deactivate an LV.

       lvchange -a|--activate y|n|ay VG|LV|Tag|Select ...
           [ -P|--partial ]
           [ -K|--ignoreactivationskip ]
           [    --activationmode partial|degraded|complete ]
           [    --poll y|n ]
           [    --monitor y|n ]
           [    --ignorelockingfailure ]
           [    --sysinit ]
           [    --readonly ]
           [ COMMON_OPTIONS ]

       —

       Reactivate an LV using the latest metadata.

       lvchange --refresh VG|LV|Tag|Select ...
           [ -P|--partial ]
           [    --activationmode partial|degraded|complete ]
           [    --poll y|n ]
           [    --monitor y|n ]
           [ COMMON_OPTIONS ]

       —

       Start or stop monitoring an LV from dmeventd.

       lvchange --monitor y|n VG|LV|Tag|Select ...
           [ COMMON_OPTIONS ]

       —

       Start or stop processing an LV conversion.

       lvchange --poll y|n VG|LV|Tag|Select ...
           [    --monitor y|n ]
           [ COMMON_OPTIONS ]

       —

       Make the minor device number persistent for an LV.

       lvchange -M|--persistent y --minor Number LV
           [ -j|--major Number ]
           [ -a|--activate y|n|ay ]
           [    --poll y|n ]
           [    --monitor y|n ]
           [ COMMON_OPTIONS ]

       —

       Common options for command:
           [ -A|--autobackup y|n ]
           [ -f|--force ]
           [ -S|--select String ]
           [    --ignoremonitoring ]
           [    --noudevsync ]
           [    --reportformat basic|json ]

       Common options for lvm:
           [ -d|--debug ]
           [ -h|--help ]
           [ -q|--quiet ]
           [ -t|--test ]
           [ -v|--verbose ]
           [ -y|--yes ]
           [    --commandprofile String ]
           [    --config String ]
           [    --devices PV ]
           [    --devicesfile String ]
           [    --driverloaded y|n ]
           [    --journal String ]
           [    --lockopt String ]
           [    --longhelp ]
           [    --nohints ]
           [    --nolocking ]
           [    --profile String ]
           [    --version ]

OPTIONS

-a|--activate y|n|ay
Change the active state of LVs. An active LV can be used through a block device, allowing data on
the LV to be accessed. y makes LVs active, or available. n makes LVs inactive, or unavailable.
The block device for the LV is added or removed from the system using device-mapper in the kernel.
A symbolic link /dev/VGName/LVName pointing to the device node is also added/removed. All soft‐
ware and scripts should access the device through the symbolic link and present this as the name
of the device. The location and name of the underlying device node may depend on the distribu‐
tion, configuration (e.g. udev), or release version. ay specifies autoactivation, which is used
by system-generated activation commands. By default, LVs are autoactivated. An autoactivation
property can be set on a VG or LV to disable autoactivation, see --setautoactivation y|n in
vgchange, lvchange, vgcreate, and lvcreate. Display the property with vgs or lvs "-o autoactiva‐
tion". The lvm.conf(5) auto_activation_volume_list includes names of VGs or LVs that should be
autoactivated, and anything not listed is not autoactivated. When auto_activation_volume_list is
undefined (the default), it has no effect. If auto_activation_volume_list is defined and empty,
no LVs are autoactivated. Items included by auto_activation_volume_list will not be autoactivated
if the autoactivation property has been disabled. See lvmlockd(8) for more information about ac‐
tivation options ey and sy for shared VGs.

--activationmode partial|degraded|complete
Determines if LV activation is allowed when PVs are missing, e.g. because of a device failure.
complete only allows LVs with no missing PVs to be activated, and is the most restrictive mode.
degraded allows RAID LVs with missing PVs to be activated. (This does not include the "mirror"
type, see "raid1" instead.) partial allows any LV with missing PVs to be activated, and should
only be used for recovery or repair. For default, see lvm.conf(5) activation_mode. See lvm‐
raid(7) for more information.

--addtag Tag
Adds a tag to a PV, VG or LV. This option can be repeated to add multiple tags at once. See lvm(8)
for information about tags.

--alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit
Determines the allocation policy when a command needs to allocate Physical Extents (PEs) from the
VG. Each VG and LV has an allocation policy which can be changed with vgchange/lvchange, or over‐
ridden on the command line. normal applies common sense rules such as not placing parallel
stripes on the same PV. inherit applies the VG policy to an LV. contiguous requires new PEs be
placed adjacent to existing PEs. cling places new PEs on the same PV as existing PEs in the same
stripe of the LV. If there are sufficient PEs for an allocation, but normal does not use them,
anywhere will use them even if it reduces performance, e.g. by placing two stripes on the same PV.
Optional positional PV args on the command line can also be used to limit which PVs the command
will use for allocation. See lvm(8) for more information about allocation.

-A|--autobackup y|n
Specifies if metadata should be backed up automatically after a change. Enabling this is strongly
advised! See vgcfgbackup(8) for more information.

--cachemode writethrough|writeback|passthrough
Specifies when writes to a cache LV should be considered complete. writeback considers a write
complete as soon as it is stored in the cache pool. writethough considers a write complete only
when it has been stored in both the cache pool and on the origin LV. While writethrough may be
slower for writes, it is more resilient if something should happen to a device associated with the
cache pool LV. With passthrough, all reads are served from the origin LV (all reads miss the
cache) and all writes are forwarded to the origin LV; additionally, write hits cause cache block
invalidates. See lvmcache(7) for more information.

--cachepolicy String
Specifies the cache policy for a cache LV. See lvmcache(7) for more information.

--cachesettings String
Specifies tunable kernel options for dm-cache or dm-writecache LVs. Use the form 'option=value'
or 'option1=value option2=value', or repeat --cachesettings for each option being set. These set‐
tings override the default kernel behaviors which are usually adequate. To remove cachesettings
and revert to the default kernel behaviors, use --cachesettings 'default' for dm-cache or an empty
string --cachesettings '' for dm-writecache. See lvmcache(7) for more information.

--commandprofile String
The command profile to use for command configuration. See lvm.conf(5) for more information about
profiles.

--compression y|n
Controls whether compression is enabled or disable for VDO volume. See lvmvdo(7) for more infor‐
mation about VDO usage.

--config String
Config settings for the command. These override lvm.conf(5) settings. The String arg uses the
same format as lvm.conf(5), or may use section/field syntax. See lvm.conf(5) for more information
about config.

-C|--contiguous y|n
Sets or resets the contiguous allocation policy for LVs. Default is no contiguous allocation
based on a next free principle. It is only possible to change a non-contiguous allocation policy
to contiguous if all of the allocated physical extents in the LV are already contiguous.

-d|--debug ...
Set debug level. Repeat from 1 to 6 times to increase the detail of messages sent to the log file
and/or syslog (if configured).

--deduplication y|n
Controls whether deduplication is enabled or disable for VDO volume. See lvmvdo(7) for more in‐
formation about VDO usage.

--deltag Tag
Deletes a tag from a PV, VG or LV. This option can be repeated to delete multiple tags at once.
See lvm(8) for information about tags.

--detachprofile
Detaches a metadata profile from a VG or LV. See lvm.conf(5) for more information about profiles.

--devices PV
Restricts the devices that are visible and accessible to the command. Devices not listed will ap‐
pear to be missing. This option can be repeated, or accepts a comma separated list of devices.
This overrides the devices file.

--devicesfile String
A file listing devices that LVM should use. The file must exist in /etc/lvm/devices/ and is man‐
aged with the lvmdevices(8) command. This overrides the lvm.conf(5) devices/devicesfile and de‐
vices/use_devicesfile settings.

--discards passdown|nopassdown|ignore
Specifies how the device-mapper thin pool layer in the kernel should handle discards. ignore
causes the thin pool to ignore discards. nopassdown causes the thin pool to process discards it‐
self to allow reuse of unneeded extents in the thin pool. passdown causes the thin pool to
process discards itself (like nopassdown) and pass the discards to the underlying device. See
lvmthin(7) for more information.

--driverloaded y|n
If set to no, the command will not attempt to use device-mapper. For testing and debugging.

--errorwhenfull y|n
Specifies thin pool behavior when data space is exhausted. When yes, device-mapper will immedi‐
ately return an error when a thin pool is full and an I/O request requires space. When no, de‐
vice-mapper will queue these I/O requests for a period of time to allow the thin pool to be ex‐
tended. Errors are returned if no space is available after the timeout. (Also see dm-thin-pool
kernel module option no_space_timeout.) See lvmthin(7) for more information.

-f|--force ...
Override various checks, confirmations and protections. Use with extreme caution.

-h|--help
Display help text.

-K|--ignoreactivationskip
Ignore the "activation skip" LV flag during activation to allow LVs with the flag set to be acti‐
vated.

--ignorelockingfailure
Allows a command to continue with read-only metadata operations after locking failures.

--ignoremonitoring
Do not interact with dmeventd unless --monitor is specified. Do not use this if dmeventd is al‐
ready monitoring a device.

--journal String
Record information in the systemd journal. This information is in addition to information enabled
by the lvm.conf log/journal setting. command: record information about the command. output:
record the default command output. debug: record full command debugging.

--lockopt String
Used to pass options for special cases to lvmlockd. See lvmlockd(8) for more information.

--longhelp
Display long help text.

-j|--major Number
Sets the major number of an LV block device.

--[raid]maxrecoveryrate Size[k|UNIT]
Sets the maximum recovery rate for a RAID LV. The rate value is an amount of data per second for
each device in the array. Setting the rate to 0 means it will be unbounded. See lvmraid(7) for
more information.

--metadataprofile String
The metadata profile to use for command configuration. See lvm.conf(5) for more information about
profiles.

--minor Number
Sets the minor number of an LV block device.

--[raid]minrecoveryrate Size[k|UNIT]
Sets the minimum recovery rate for a RAID LV. The rate value is an amount of data per second for
each device in the array. Setting the rate to 0 means it will be unbounded. See lvmraid(7) for
more information.

--monitor y|n
Start (yes) or stop (no) monitoring an LV with dmeventd. dmeventd monitors kernel events for an
LV, and performs automated maintenance for the LV in reponse to specific events. See dmeventd(8)
for more information.

--nohints
Do not use the hints file to locate devices for PVs. A command may read more devices to find PVs
when hints are not used. The command will still perform standard hint file invalidation where ap‐
propriate.

--nolocking
Disable locking. Use with caution, concurrent commands may produce incorrect results.

--noudevsync
Disables udev synchronisation. The process will not wait for notification from udev. It will con‐
tinue irrespective of any possible udev processing in the background. Only use this if udev is not
running or has rules that ignore the devices LVM creates.

-P|--partial
Commands will do their best to activate LVs with missing PV extents. Missing extents may be re‐
placed with error or zero segments according to the missing_stripe_filler setting. Metadata may
not be changed with this option.

-p|--permission rw|r
Set access permission to read only r or read and write rw.

-M|--persistent y|n
When yes, makes the specified minor number persistent.

--poll y|n
When yes, start the background transformation of an LV. An incomplete transformation, e.g. pvmove
or lvconvert interrupted by reboot or crash, can be restarted from the last checkpoint with --poll
y. When no, background transformation of an LV will not occur, and the transformation will not
complete. It may not be appropriate to immediately poll an LV after activation, in which case
--poll n can be used to defer polling until a later --poll y command.

--profile String
An alias for --commandprofile or --metadataprofile, depending on the command.

-q|--quiet ...
Suppress output and log messages. Overrides --debug and --verbose. Repeat once to also suppress
any prompts with answer 'no'.

-r|--readahead auto|none|Number
Sets read ahead sector count of an LV. auto is the default which allows the kernel to choose a
suitable value automatically. none is equivalent to zero.

--readonly
Run the command in a special read-only mode which will read on-disk metadata without needing to
take any locks. This can be used to peek inside metadata used by a virtual machine image while the
virtual machine is running. No attempt will be made to communicate with the device-mapper kernel
driver, so this option is unable to report whether or not LVs are actually in use.

--rebuild PV
Selects a PV to rebuild in a raid LV. Multiple PVs can be rebuilt by repeating this option. Use
this option in place of --resync or --syncaction repair when the PVs with corrupted data are
known, and their data should be reconstructed rather than reconstructing default (rotating) data.
See lvmraid(7) for more information.

--refresh
If the LV is active, reload its metadata. This is not necessary in normal operation, but may be
useful if something has gone wrong, or if some form of manual LV sharing is being used.

--reportformat basic|json
Overrides current output format for reports which is defined globally by the report/output_format
setting in lvm.conf(5). basic is the original format with columns and rows. If there is more
than one report per command, each report is prefixed with the report name for identification. json
produces report output in JSON format. See lvmreport(7) for more information.

--resync
Initiates mirror synchronization. Synchronization generally happens automatically, but this option
forces it to run. Also see --rebuild to synchronize a specific PV. During synchronization, data
is read from the primary mirror device and copied to the others. This can take considerable time,
during which the LV is without a complete redundant copy of the data. See lvmraid(7) for more in‐
formation.

-S|--select String
Select objects for processing and reporting based on specified criteria. The criteria syntax is
described by --select help and lvmreport(7). For reporting commands, one row is displayed for
each object matching the criteria. See --options help for selectable object fields. Rows can be
displayed with an additional "selected" field (-o selected) showing 1 if the row matches the se‐
lection and 0 otherwise. For non-reporting commands which process LVM entities, the selection is
used to choose items to process.

-k|--setactivationskip y|n
Persistently sets (yes) or clears (no) the "activation skip" flag on an LV. An LV with this flag
set is not activated unless the --ignoreactivationskip option is used by the activation command.
This flag is set by default on new thin snapshot LVs. The flag is not applied to deactivation.
The current value of the flag is indicated in the lvs lv_attr bits.

--setautoactivation y|n
Set the autoactivation property on a VG or LV. Display the property with vgs or lvs "-o autoacti‐
vation". When the autoactivation property is disabled, the VG or LV will not be activated by a
command doing autoactivation (vgchange, lvchange, or pvscan using -aay.) If autoactivation is
disabled on a VG, no LVs will be autoactivated in that VG, and the LV autoactivation property has
no effect. If autoactivation is enabled on a VG, autoactivation can be disabled for individual
LVs.

--[raid]syncaction check|repair
Initiate different types of RAID synchronization. This causes the RAID LV to read all data and
parity blocks in the array and check for discrepancies (mismatches between mirrors or incorrect
parity values). check will count but not correct discrepancies. repair will correct discrepan‐
cies. See lvs(8) for reporting discrepancies found or repaired.

--sysinit
Indicates that vgchange/lvchange is being invoked from early system initialisation scripts (e.g.
rc.sysinit or an initrd), before writable filesystems are available. As such, some functionality
needs to be disabled and this option acts as a shortcut which selects an appropriate set of op‐
tions. Currently, this is equivalent to using --ignorelockingfailure, --ignoremonitoring, --poll
n, and setting env var LVM_SUPPRESS_LOCKING_FAILURE_MESSAGES. vgchange/lvchange skip autoactiva‐
tion, and defer to pvscan autoactivation.

-t|--test
Run in test mode. Commands will not update metadata. This is implemented by disabling all metada‐
ta writing but nevertheless returning success to the calling function. This may lead to unusual
error messages in multi-stage operations if a tool relies on reading back metadata it believes has
changed but hasn't.

--vdosettings String
Specifies tunable VDO options for VDO LVs. Use the form 'option=value' or 'option1=value op‐
tion2=value', or repeat --vdosettings for each option being set. These settings override the de‐
fault VDO behaviors. To remove vdosettings and revert to the default VDO behaviors, use --vdoset‐
tings 'default'. See lvmvdo(7) for more information.

-v|--verbose ...
Set verbose level. Repeat from 1 to 4 times to increase the detail of messages sent to stdout and
stderr.

--version
Display version information.

--[raid]writebehind Number
The maximum number of outstanding writes that are allowed to devices in a RAID1 LV that is marked
write-mostly. Once this value is exceeded, writes become synchronous (i.e. all writes to the con‐
stituent devices must complete before the array signals the write has completed). Setting the val‐
ue to zero clears the preference and allows the system to choose the value arbitrarily.

--[raid]writemostly PV[:t|n|y]
Mark a device in a RAID1 LV as write-mostly. All reads to these drives will be avoided unless ab‐
solutely necessary. This keeps the number of I/Os to the drive to a minimum. The default behavior
is to set the write-mostly attribute for the specified PV. It is also possible to remove the
write-mostly flag by adding the suffix :n at the end of the PV name, or to toggle the value with
the suffix :t. Repeat this option to change the attribute on multiple PVs.

-y|--yes
Do not prompt for confirmation interactively but always assume the answer yes. Use with extreme
caution. (For automatic no, see -qq.)

-Z|--zero y|n
Set zeroing mode for thin pool. Note: already provisioned blocks from pool in non-zero mode are
not cleared in unwritten parts when setting --zero y.

VARIABLES

       VG     Volume Group name.  See lvm(8) for valid names.

       LV     Logical Volume name.  See lvm(8) for valid names.  An LV positional arg generally includes the  VG
              name  and LV name, e.g. VG/LV.  LV1 indicates the LV must have a specific type, where the accepted
              LV types are listed. (raid represents raid<N> type).

       Tag    Tag name.  See lvm(8) for information about tag names and using tags in place of a VG, LV or PV.

       Select Select indicates that a required positional parameter can be omitted if  the  --select  option  is
              used.  No arg appears in this position.

       String See the option description for information about the string content.

       Size[UNIT]
              Size is an input number that accepts an optional unit.  Input units are always treated as base two
              values, regardless of capitalization, e.g. 'k' and 'K' both refer to 1024.  The default input unit
              is  specified  by  letter,  followed by |UNIT.  UNIT represents other possible input units: b|B is
              bytes, s|S is sectors of 512 bytes, k|K is KiB, m|M is MiB, g|G is GiB, t|T is TiB,  p|P  is  PiB,
              e|E  is  EiB.  (This should not be confused with the output control --units, where capital letters
              mean multiple of 1000.)

ENVIRONMENT VARIABLES

       See lvm(8) for information about environment variables used by lvm.  For example, LVM_VG_NAME can  gener‐
       ally be substituted for a required VG parameter.

EXAMPLES

       Change LV permission to read-only:
       lvchange -pr vg00/lvol1