table of contents
LVCONVERT(8) | System Manager's Manual | LVCONVERT(8) |
NAME¶
lvconvert - Change logical volume layoutSYNOPSIS¶
lvconvert option_args position_args [ option_args ] [ position_args ]--alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit -b|--background -H|--cache --cachemetadataformat auto|1|2 --cachemode writethrough|writeback|passthrough --cachepolicy String --cachepool LV --cachesettings String -c|--chunksize Size[k|UNIT] --commandprofile String --compression y|n --config String -d|--debug --deduplication y|n --discards passdown|nopassdown|ignore --driverloaded y|n -f|--force -h|--help -i|--interval Number --lockopt String --longhelp --merge --mergemirrors --mergesnapshot --mergethin --metadataprofile String --mirrorlog core|disk -m|--mirrors [+|-]Number -n|--name String --nolocking --noudevsync --originname LV --poolmetadata LV --poolmetadatasize Size[m|UNIT] --poolmetadataspare y|n --profile String -q|--quiet -r|--readahead auto|none|Number -R|--regionsize Size[m|UNIT] --repair --replace PV -s|--snapshot --splitcache --splitmirrors Number --splitsnapshot --startpoll --stripes Number -I|--stripesize Size[k|UNIT] --swapmetadata -t|--test -T|--thin --thinpool LV --trackchanges --type linear|striped|snapshot|mirror|raid|thin|cache|thin-pool|cache-pool --uncache --usepolicies --vdopool LV -v|--verbose --version -V|--virtualsize Size[m|UNIT] -y|--yes -Z|--zero y|n
DESCRIPTION¶
lvconvert changes the LV type and includes utilities for LV data maintenance. The LV type controls data layout and redundancy. The LV type is also called the segment type or segtype.To display the current LV type, run the command:
lvs -o name,segtype LV
In some cases, an LV is a single device mapper (dm) layer above physical devices. In other cases, hidden LVs (dm devices) are layered between the visible LV and physical devices. LVs in the middle layers are called sub LVs. A command run on a visible LV sometimes operates on a sub LV rather than the specified LV. In other cases, a sub LV must be specified directly on the command line.
Sub LVs can be displayed with the command:
lvs -a
The linear type is equivalent to the striped type when one stripe exists. In that case, the types can sometimes be used interchangably.
In most cases, the mirror type is deprecated and the raid1 type should be used. They are both implementations of mirroring.
Striped raid types are raid0/raid0_meta, raid5 (an alias for raid5_ls), raid6 (an alias for raid6_zr) and raid10 (an alias for raid10_near).
As opposed to mirroring, raid5 and raid6 stripe data and calculate parity blocks. The parity blocks can be used for data block recovery in case devices fail. A maximum number of one device in a raid5 LV may fail, and two in case of raid6. Striped raid types typically rotate the parity and data blocks for performance reasons, thus avoiding contention on a single device. Specific arrangements of parity and data blocks (layouts) can be used to optimize I/O performance, or to convert between raid levels. See lvmraid(7) for more information.
Layouts of raid5 rotating parity blocks can be: left-asymmetric (raid5_la), left-symmetric (raid5_ls with alias raid5), right-asymmetric (raid5_ra), right-symmetric (raid5_rs) and raid5_n, which doesn't rotate parity blocks. Layouts of raid6 are: zero-restart (raid6_zr with alias raid6), next-restart (raid6_nr), and next-continue (raid6_nc).
Layouts including _n allow for conversion between raid levels (raid5_n to raid6 or raid5_n to striped/raid0/raid0_meta). Additionally, special raid6 layouts for raid level conversions between raid5 and raid6 are: raid6_ls_6, raid6_rs_6, raid6_la_6 and raid6_ra_6. Those correspond to their raid5 counterparts (e.g. raid5_rs can be directly converted to raid6_rs_6 and vice-versa).
raid10 (an alias for raid10_near) is currently limited to one data copy and even number of sub LVs. This is a mirror group layout, thus a single sub LV may fail per mirror group without data loss.
Striped raid types support converting the layout, their stripesize and their number of stripes.
The striped raid types combined with raid1 allow for conversion from linear-> striped/raid0/raid0_meta and vice-versa by e.g. linear <-> raid1 <-> raid5_n (then adding stripes) <-> striped/raid0/raid0_meta.
USAGE¶
Convert LV to linear.lvconvert --type linear LV
Convert LV to striped.
lvconvert --type striped LV
[ -R|--regionsize Size[m|UNIT] ]
[ -i|--interval Number ]
[ --stripes Number ]
[ COMMON_OPTIONS ]
Convert LV to raid or change raid layout
(a specific raid level must be used, e.g. raid1).
lvconvert --type raid LV
[ -I|--stripesize Size[k|UNIT] ]
[ -R|--regionsize Size[m|UNIT] ]
[ -i|--interval Number ]
[ --stripes Number ]
[ COMMON_OPTIONS ]
Convert LV to raid1 or mirror, or change number of mirror images.
lvconvert -m|--mirrors
[+|-]Number LV
[ -i|--interval Number ]
[ --mirrorlog core|disk ]
[ COMMON_OPTIONS ]
Convert raid LV to change number of stripe images.
lvconvert --stripes Number
LV_raid
[ -R|--regionsize Size[m|UNIT] ]
[ -I|--stripesize Size[k|UNIT] ]
[ COMMON_OPTIONS ]
Convert raid LV to change the stripe size.
lvconvert -I|--stripesize Size[k|UNIT]
LV_raid
[ -R|--regionsize Size[m|UNIT] ]
[ COMMON_OPTIONS ]
-
Split images from a raid1 or mirror LV and use them to create a
new LV.
lvconvert --splitmirrors Number
-n|--name LV_new
LV_cache_mirror_raid1
Split images from a raid1 LV and track changes to origin for later
merge.
lvconvert --splitmirrors Number
--trackchanges LV_cache_raid1
Merge LV images that were split from a raid1 LV.
lvconvert --mergemirrors
VG|LV_linear_raid|Tag ...
-
Convert LV to a thin LV, using the original LV as an external
origin.
lvconvert --type thin --thinpool
LV LV_linear_striped_thin_cache_raid
[ -r|--readahead auto|none|Number ]
[ -c|--chunksize Size[k|UNIT] ]
[ -Z|--zero y|n ]
[ --originname LV_new ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
-
Convert LV to type cache.
lvconvert --type cache --cachepool
LV LV_linear_striped_thinpool_raid
[ -Z|--zero y|n ]
[ -r|--readahead auto|none|Number ]
[ -c|--chunksize Size[k|UNIT] ]
[ --cachemetadataformat auto|1|2 ]
[ --cachemode writethrough|writeback|passthrough ]
[ --cachepolicy String ]
[ --cachesettings String ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
-
Convert LV to type thin-pool.
lvconvert --type thin-pool
LV_linear_striped_cache_raid
[ -r|--readahead auto|none|Number ]
[ -c|--chunksize Size[k|UNIT] ]
[ -Z|--zero y|n ]
[ --stripes Number ]
[ --discards passdown|nopassdown|ignore ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
Convert LV to type cache-pool.
lvconvert --type cache-pool
LV_linear_striped_raid
[ -r|--readahead auto|none|Number ]
[ -c|--chunksize Size[k|UNIT] ]
[ --cachemetadataformat auto|1|2 ]
[ --cachemode writethrough|writeback|passthrough ]
[ --cachepolicy String ]
[ --cachesettings String ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
Convert LV to type vdopool.
lvconvert --type vdo-pool
LV_linear_striped_cache_raid
[ -V|--virtualsize Size[m|UNIT] ]
[ --compression y|n ]
[ --deduplication y|n ]
[ COMMON_OPTIONS ]
-
Separate and keep the cache pool from a cache LV.
lvconvert --splitcache
LV_thinpool_cache_cachepool
-
Merge thin LV into its origin LV.
lvconvert --mergethin LV_thin ...
-
Merge COW snapshot LV into its origin.
lvconvert --mergesnapshot LV_snapshot
...
[ COMMON_OPTIONS ]
-
Combine a former COW snapshot (second arg) with a former
origin LV (first arg) to reverse a splitsnapshot command.
lvconvert --type snapshot LV
LV_linear_striped
[ -c|--chunksize Size[k|UNIT] ]
[ -Z|--zero y|n ]
[ COMMON_OPTIONS ]
-
Replace failed PVs in a raid or mirror LV.
Repair a thin pool.
Repair a cache pool.
lvconvert --repair
LV_thinpool_cache_cachepool_mirror_raid
[ --usepolicies ]
[ --poolmetadataspare y|n ]
[ COMMON_OPTIONS ]
Replace specific PV(s) in a raid LV with another PV.
lvconvert --replace PV LV_raid
Poll LV to continue conversion.
lvconvert --startpoll LV_mirror_raid
-
Common options for command:
[ -f|--force ]
[ --alloc contiguous|cling|cling_by_tags|normal|anywhere|inherit ]
[ --noudevsync ]
Common options for lvm:
[ -h|--help ]
[ -q|--quiet ]
[ -t|--test ]
[ -v|--verbose ]
[ -y|--yes ]
[ --commandprofile String ]
[ --config String ]
[ --driverloaded y|n ]
[ --lockopt String ]
[ --longhelp ]
[ --nolocking ]
[ --profile String ]
[ --version ]
OPTIONS¶
--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 overriden 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.
-b|--background
If the operation requires polling, this option causes the command to return
before the operation is complete, and polling is done in the background.
-H|--cache
Specifies the command is handling a cache LV or cache pool. See --type cache
and --type cache-pool. See lvmcache(7) for more information about LVM
caching.
--cachemetadataformat auto|1|2
Specifies the cache metadata format used by cache target.
--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.
--cachepool LV
The name of a cache pool LV.
--cachesettings String
Specifies tunable values for a cache LV in "Key = Value" form.
Repeat this option to specify multiple values. (The default values should
usually be adequate.) The special string value default switches
settings back to their default kernel values and removes them from the list
of settings stored in LVM metadata. See lvmcache(7) for more
information.
-c|--chunksize Size[k|UNIT]
The size of chunks in a snapshot, cache pool or thin pool. For snapshots, the
value must be a power of 2 between 4KiB and 512KiB and the default value is
4. For a cache pool the value must be between 32KiB and 1GiB and the default
value is 64. For a thin pool the value must be between 64KiB and 1GiB and
the default value starts with 64 and scales up to fit the pool metadata size
within 128MiB, if the pool metadata size is not specified. The value must be
a multiple of 64KiB. See lvmthin(7) and 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 information about VDO usage.
--config String
Config settings for the command. These override lvm.conf settings. The String
arg uses the same format as lvm.conf, or may use section/field syntax. See
lvm.conf(5) for more information about config.
-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 information about VDO usage.
--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 itself 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.
-f|--force ...
Override various checks, confirmations and protections. Use with extreme
caution.
-h|--help
Display help text.
-i|--interval Number
Report progress at regular intervals.
--lockopt String
Used to pass options for special cases to lvmlockd. See lvmlockd(8) for
more information.
--longhelp
Display long help text.
--merge
An alias for --mergethin, --mergemirrors, or --mergesnapshot, depending on the
type of LV.
--mergemirrors
Merge LV images that were split from a raid1 LV. See --splitmirrors with
--trackchanges.
--mergesnapshot
Merge COW snapshot LV into its origin. When merging a snapshot, if both the
origin and snapshot LVs are not open, the merge will start immediately.
Otherwise, the merge will start the first time either the origin or snapshot
LV are activated and both are closed. Merging a snapshot into an origin that
cannot be closed, for example a root filesystem, is deferred until the next
time the origin volume is activated. When merging starts, the resulting LV
will have the origin's name, minor number and UUID. While the merge is in
progress, reads or writes to the origin appear as being directed to the
snapshot being merged. When the merge finishes, the merged snapshot is
removed. Multiple snapshots may be specified on the command line or a @tag
may be used to specify multiple snapshots be merged to their respective
origin.
--mergethin
Merge thin LV into its origin LV. The origin thin LV takes the content of the
thin snapshot, and the thin snapshot LV is removed. See lvmthin(7)
for more information.
--metadataprofile String
The metadata profile to use for command configuration. See lvm.conf(5)
for more information about profiles.
--mirrorlog core|disk
Specifies the type of mirror log for LVs with the "mirror" type
(does not apply to the "raid1" type.) disk is a persistent
log and requires a small amount of storage space, usually on a separate
device from the data being mirrored. core is not persistent; the log
is kept only in memory. In this case, the mirror must be synchronized (by
copying LV data from the first device to others) each time the LV is
activated, e.g. after reboot. mirrored is a persistent log that is
itself mirrored, but should be avoided. Instead, use the raid1 type for log
redundancy.
-m|--mirrors [+|-]Number
Specifies the number of mirror images in addition to the original LV image,
e.g. --mirrors 1 means there are two images of the data, the original and
one mirror image. Optional positional PV args on the command line can
specify the devices the images should be placed on. There are two mirroring
implementations: "raid1" and "mirror". These are the
names of the corresponding LV types, or "segment types". Use the
--type option to specify which to use (raid1 is default, and mirror is
legacy) Use lvm.conf global/mirror_segtype_default and
global/raid10_segtype_default to configure the default types. The plus
prefix + can be used, in which case the number is added to the
current number of images, or the minus prefix - can be used, in which
case the number is subtracted from the current number of images. See
lvmraid(7) for more information.
-n|--name String
Specifies the name of a new LV. When unspecified, a default name of
"lvol#" is generated, where # is a number generated by LVM.
--nolocking
Disable locking.
--noudevsync
Disables udev synchronisation. The process will not wait for notification from
udev. It will continue 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.
--originname LV
Specifies the name to use for the external origin LV when converting an LV to
a thin LV. The LV being converted becomes a read-only external origin with
this name.
--poolmetadata LV
The name of a an LV to use for storing pool metadata.
--poolmetadatasize Size[m|UNIT]
Specifies the size of the new pool metadata LV.
--poolmetadataspare y|n
Enable or disable the automatic creation and management of a spare pool
metadata LV in the VG. A spare metadata LV is reserved space that can be
used when repairing a pool.
--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.
-R|--regionsize Size[m|UNIT]
Size of each raid or mirror synchronization region. lvm.conf
activation/raid_region_size can be used to configure a default.
--repair
Replace failed PVs in a raid or mirror LV, or run a repair utility on a thin
pool. See lvmraid(7) and lvmthin(7) for more information.
--replace PV
Replace a specific PV in a raid LV with another PV. The new PV to use can be
optionally specified after the LV. Multiple PVs can be replaced by repeating
this option. See lvmraid(7) for more information.
-s|--snapshot
Combine a former COW snapshot LV with a former origin LV to reverse a previous
--splitsnapshot command.
--splitcache
Separates a cache pool from a cache LV, and keeps the unused cache pool LV.
Before the separation, the cache is flushed. Also see --uncache.
--splitmirrors Number
Splits the specified number of images from a raid1 or mirror LV and uses them
to create a new LV. If --trackchanges is also specified, changes to the
raid1 LV are tracked while the split LV remains detached. If --name is
specified, then the images are permanently split from the original LV and
changes are not tracked.
--splitsnapshot
Separates a COW snapshot from its origin LV. The LV that is split off contains
the chunks that differ from the origin LV along with metadata describing
them. This LV can be wiped and then destroyed with lvremove.
--startpoll
Start polling an LV to continue processing a conversion.
--stripes Number
Specifies the number of stripes in a striped LV. This is the number of PVs
(devices) that a striped LV is spread across. Data that appears sequential
in the LV is spread across multiple devices in units of the stripe size (see
--stripesize). This does not apply to existing allocated space, only newly
allocated space can be striped.
-I|--stripesize Size[k|UNIT]
The amount of data that is written to one device before moving to the next in
a striped LV.
--swapmetadata
Extracts the metadata LV from a pool and replaces it with another specified
LV. The extracted LV is preserved and given the name of the LV that replaced
it. Use for repair only. When the metadata LV is swapped out of the pool, it
can be activated directly and used with thin provisioning tools:
cache_dump(8), cache_repair(8), cache_restore(8),
thin_dump(8), thin_repair(8), thin_restore(8).
-t|--test
Run in test mode. Commands will not update metadata. This is implemented by
disabling all metadata 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.
-T|--thin
Specifies the command is handling a thin LV or thin pool. See --type thin,
--type thin-pool, and --virtualsize. See lvmthin(7) for more
information about LVM thin provisioning.
--thinpool LV
The name of a thin pool LV.
--trackchanges
Can be used with --splitmirrors on a raid1 LV. This causes changes to the
original raid1 LV to be tracked while the split images remain detached. This
is a temporary state that allows the read-only detached image to be merged
efficiently back into the raid1 LV later. Only the regions with changed data
are resynchronized during merge. While a raid1 LV is tracking changes,
operations on it are limited to merging the split image (see --mergemirrors)
or permanently splitting the image (see --splitmirrors with --name.
--type
linear|striped|snapshot|mirror|raid|thin|cache|thin-pool|cache-pool
The LV type, also known as "segment type" or "segtype".
See usage descriptions for the specific ways to use these types. For more
information about redundancy and performance (raid<N>,
mirror, striped, linear) see lvmraid(7). For
thin provisioning (thin, thin-pool) see lvmthin(7). For
performance caching (cache, cache-pool) see
lvmcache(7). For copy-on-write snapshots (snapshot) see usage
definitions. Several commands omit an explicit type option because the type
is inferred from other options or shortcuts (e.g. --stripes, --mirrors,
--snapshot, --virtualsize, --thin, --cache). Use inferred types with care
because it can lead to unexpected results.
--uncache
Separates a cache pool from a cache LV, and deletes the unused cache pool LV.
Before the separation, the cache is flushed. Also see --splitcache.
--usepolicies
Perform an operation according to the policy configured in lvm.conf or a
profile.
--vdopool LV
The name of a VDO pool LV. See lvmvdo(7) for more information about VDO
usage.
-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.
-V|--virtualsize Size[m|UNIT]
The virtual size of a new thin LV. See lvmthin(7) for more information
about LVM thin provisioning. Using virtual size (-V) and actual size (-L)
together creates a sparse LV. lvm.conf global/sparse_segtype_default
determines the default segment type used to create a sparse LV. Anything
written to a sparse LV will be returned when reading from it. Reading from
other areas of the LV will return blocks of zeros. When using a snapshot to
create a sparse LV, a hidden virtual device is created using the zero
target, and the LV has the suffix _vorigin. Snapshots are less efficient
than thin provisioning when creating large sparse LVs (GiB).
-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
For snapshots, this controls zeroing of the first 4KiB of data in the
snapshot. If the LV is read-only, the snapshot will not be zeroed. For thin
pools, this controls zeroing of provisioned blocks. Provisioning of large
zeroed chunks negatively impacts performance.
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. LV followed by
_<type> indicates that an LV of the given type is required. (raid
represents raid<N> type)
PV
Physical Volume name, a device path under /dev. For commands managing physical
extents, a PV positional arg generally accepts a suffix indicating a range
(or multiple ranges) of physical extents (PEs). When the first PE is
omitted, it defaults to the start of the device, and when the last PE is
omitted it defaults to end. Start and end range (inclusive):
PV[:PE-PE]... Start and length range
(counting from 0): PV[:PE+PE]...
Tag
Tag name. See lvm(8) for information about tag names and using tags in
place of a VG, LV or PV.
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:
bBsSkKmMgGtTpPeE. b|B is bytes, s|S is sectors of 512 bytes, k|K is
kilobytes, m|M is megabytes, g|G is gigabytes, t|T is terabytes, p|P is
petabytes, e|E is exabytes. (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 generally be substituted for a required VG parameter.ADVANCED USAGE¶
Alternate command forms, advanced command usage, and listing of all valid syntax for completeness.Convert LV to type mirror (also see type raid1),
(also see lvconvert --mirrors).
lvconvert --type mirror LV
[ -R|--regionsize Size[m|UNIT] ]
[ -i|--interval Number ]
[ --mirrorlog core|disk ]
[ COMMON_OPTIONS ]
Change the region size of an LV.
lvconvert -R|--regionsize Size[m|UNIT]
LV_raid
-
Change the type of mirror log used by a mirror LV.
lvconvert --mirrorlog core|disk
LV_mirror
Convert LV to a thin LV, using the original LV as an external
origin
(infers --type thin).
lvconvert -T|--thin --thinpool
LV LV_linear_striped_thin_cache_raid
[ -c|--chunksize Size[k|UNIT] ]
[ -Z|--zero y|n ]
[ --type thin ]
[ --originname LV_new ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
-
Convert LV to type cache (infers --type cache).
lvconvert -H|--cache --cachepool
LV LV_linear_striped_thinpool_raid
[ -r|--readahead auto|none|Number ]
[ -c|--chunksize Size[k|UNIT] ]
[ --type cache ]
[ --cachemetadataformat auto|1|2 ]
[ --cachemode writethrough|writeback|passthrough ]
[ --cachepolicy String ]
[ --cachesettings String ]
[ --poolmetadata LV ]
[ --poolmetadatasize Size[m|UNIT] ]
[ --poolmetadataspare y|n ]
[ --metadataprofile String ]
[ COMMON_OPTIONS ]
-
Convert LV to type vdopool.
lvconvert --vdopool
LV_linear_striped_cache_raid
[ -V|--virtualsize Size[m|UNIT] ]
[ --type vdo-pool ]
[ --compression y|n ]
[ --deduplication y|n ]
[ COMMON_OPTIONS ]
-
Separate and delete the cache pool from a cache LV.
lvconvert --uncache LV_thinpool_cache
-
Swap metadata LV in a thin pool or cache pool (for repair only).
lvconvert --swapmetadata --poolmetadata
LV LV_thinpool_cachepool
[ COMMON_OPTIONS ]
-
Merge LV that was split from a mirror (variant, use
--mergemirrors).
Merge thin LV into its origin LV (variant, use --mergethin).
Merge COW snapshot LV into its origin (variant, use --mergesnapshot).
lvconvert --merge
VG|LV_linear_striped_snapshot_thin_raid|Tag ...
[ COMMON_OPTIONS ]
-
Separate a COW snapshot from its origin LV.
lvconvert --splitsnapshot LV_snapshot
-
Combine a former COW snapshot (second arg) with a former
origin LV (first arg) to reverse a splitsnapshot command.
lvconvert -s|--snapshot LV
LV_linear_striped
[ -Z|--zero y|n ]
[ --type snapshot ]
[ COMMON_OPTIONS ]
-
Poll LV to continue conversion (also see --startpoll)
or waits till conversion/mirror syncing is finished
lvconvert LV_mirror_raid
-
NOTES¶
This previous command syntax would perform two different operations:lvconvert --thinpool LV1 --poolmetadata LV2
If LV1 was not a thin pool, the command would convert LV1 to a thin pool, optionally using a specified LV for metadata. But, if LV1 was already a thin pool, the command would swap the current metadata LV with LV2 (for repair purposes.)
In the same way, this previous command syntax would perform two
different operations:
lvconvert --cachepool LV1 --poolmetadata LV2
If LV1 was not a cache pool, the command would convert LV1 to a cache pool,
optionally using a specified LV for metadata. But, if LV1 was already a
cache pool, the command would swap the current metadata LV with LV2 (for
repair purposes.)
EXAMPLES¶
Convert a linear LV to a two-way mirror LV.lvconvert --type mirror --mirrors 1 vg/lvol1
Convert a linear LV to a two-way RAID1 LV.
lvconvert --type raid1 --mirrors 1 vg/lvol1
Convert a mirror LV to use an in-memory log.
lvconvert --mirrorlog core vg/lvol1
Convert a mirror LV to use a disk log.
lvconvert --mirrorlog disk vg/lvol1
Convert a mirror or raid1 LV to a linear LV.
lvconvert --type linear vg/lvol1
Convert a mirror LV to a raid1 LV with the same number of images.
lvconvert --type raid1 vg/lvol1
Convert a linear LV to a two-way mirror LV, allocating new extents
from specific PV ranges.
lvconvert --mirrors 1 vg/lvol1 /dev/sda:0-15 /dev/sdb:0-15
Convert a mirror LV to a linear LV, freeing physical extents from
a specific PV.
lvconvert --type linear vg/lvol1 /dev/sda
Split one image from a mirror or raid1 LV, making it a new LV.
lvconvert --splitmirrors 1 --name lv_split vg/lvol1
Split one image from a raid1 LV, and track changes made to the
raid1 LV while the split image remains detached.
lvconvert --splitmirrors 1 --trackchanges vg/lvol1
Merge an image (that was previously created with --splitmirrors
and --trackchanges) back into the original raid1 LV.
lvconvert --mergemirrors vg/lvol1_rimage_1
Replace PV /dev/sdb1 with PV /dev/sdf1 in a raid1/4/5/6/10 LV.
lvconvert --replace /dev/sdb1 vg/lvol1 /dev/sdf1
Replace 3 PVs /dev/sd[b-d]1 with PVs /dev/sd[f-h]1 in a raid1 LV.
lvconvert --replace /dev/sdb1 --replace /dev/sdc1 --replace
/dev/sdd1
Replace the maximum of 2 PVs /dev/sd[bc]1 with PVs /dev/sd[gh]1 in
a raid6 LV.
lvconvert --replace /dev/sdb1 --replace /dev/sdc1 vg/lvol1
/dev/sd[gh]1
Convert an LV into a thin LV in the specified thin pool. The
existing LV is used as an external read-only origin for the new thin LV.
lvconvert --type thin --thinpool vg/tpool1 vg/lvol1
Convert an LV into a thin LV in the specified thin pool. The
existing LV is used as an external read-only origin for the new thin LV, and
is renamed "external".
lvconvert --type thin --thinpool vg/tpool1
Convert an LV to a cache pool LV using another specified LV for
cache pool metadata.
lvconvert --type cache-pool --poolmetadata vg/poolmeta1 vg/lvol1
Convert an LV to a cache LV using the specified cache pool and
chunk size.
lvconvert --type cache --cachepool vg/cpool1 -c 128 vg/lvol1
Detach and keep the cache pool from a cache LV.
lvconvert --splitcache vg/lvol1
Detach and remove the cache pool from a cache LV.
lvconvert --uncache vg/lvol1
SEE ALSO¶
lvm(8) lvm.conf(5) lvmconfig(8)pvchange(8) pvck(8) pvcreate(8) pvdisplay(8) pvmove(8) pvremove(8) pvresize(8) pvs(8) pvscan(8)
vgcfgbackup(8) vgcfgrestore(8) vgchange(8) vgck(8) vgcreate(8) vgconvert(8) vgdisplay(8) vgexport(8) vgextend(8) vgimport(8) vgimportclone(8) vgmerge(8) vgmknodes(8) vgreduce(8) vgremove(8) vgrename(8) vgs(8) vgscan(8) vgsplit(8)
lvcreate(8) lvchange(8) lvconvert(8) lvdisplay(8) lvextend(8) lvreduce(8) lvremove(8) lvrename(8) lvresize(8) lvs(8) lvscan(8)
lvm-fullreport(8) lvm-lvpoll(8) lvm2-activation-generator(8) blkdeactivate(8) lvmdump(8)
dmeventd(8) lvmpolld(8) lvmlockd(8) lvmlockctl(8) cmirrord(8) lvmdbusd(8)
lvmsystemid(7) lvmreport(7) lvmraid(7) lvmthin(7) lvmcache(7)
LVM TOOLS 2.03.02(2) (2018-12-18) | Red Hat, Inc. |