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LVM.CONF(5)                            File Formats Manual                            LVM.CONF(5)

       lvm.conf — Configuration file for LVM2


       lvm.conf  is loaded during the initialisation phase of lvm(8).  This file can in turn lead
       to other files being loaded - settings read in  later  override  earlier  settings.   File
       timestamps  are  checked  between  commands  and  if  any  have changed, all the files are

       The settings defined in lvm.conf can be overridden by any of these extended  configuration

       direct config override on command line
              The  --config ConfigurationString command line option takes the ConfigurationString
              as direct string representation of the configuration to override the existing  con‐
              figuration.  The  ConfigurationString  is of exactly the same format as used in any
              LVM configuration file.

       profile config
              A profile is a set of selected customizable configuration settings that  are  aimed
              to  achieve a certain characteristics in various environments or uses. It's used to
              override existing configuration.  Normally, the name of the profile should  reflect
              that environment or use.

              There  are  two  groups  of profiles recognised: command profiles and metadata pro‐

              The command profile is used to override selected configuration settings  at  global
              LVM  command  level  - it is applied at the very beginning of LVM command execution
              and it is used throughout the whole time of LVM command execution. The command pro‐
              file  is applied by using the --commandprofile ProfileName command line option that
              is recognised by all LVM2 commands.

              The metadata profile is used to override selected configuration settings at  Volume
              Group/Logical Volume level - it is applied independently for each Volume Group/Log‐
              ical Volume that is being processed. As such, each Volume Group/Logical Volume  can
              store  the  profile name used in its metadata so next time the Volume Group/Logical
              Volume is processed, the profile is applied automatically. If Volume Group and  any
              of its Logical Volumes have different profiles defined, the profile defined for the
              Logical Volume is preferred. The metadata profile can be attached/detached by using
              the  lvchange  and  vgchange  commands  and their --metadataprofile ProfileName and
              --detachprofile options or the --metadataprofile option during creation when  using
              vgcreate  or  lvcreate  command.   The  vgs  and  lvs reporting commands provide -o
              vg_profile and -o lv_profile output options to show the metadata profile  currently
              attached to a Volume Group or a Logical Volume.

              The set of options allowed for command profiles is mutually exclusive when compared
              to the set of options allowed for metadata profiles. The settings  that  belong  to
              either  of  these  two  sets can't be mixed together and LVM tools will reject such

              LVM itself provides a few predefined configuration profiles.  Users are allowed  to
              add  more  profiles with different values if needed.  For this purpose, there's the
              command_profile_template.profile (for command profiles)  and  metadata_profile_tem‐
              plate.profile (for metadata profiles) which contain all settings that are customiz‐
              able by profiles of certain type. Users are encouraged to copy these template  pro‐
              files  and  edit them as needed. Alternatively, the lvm dumpconfig --file <Profile‐
              Name.profile> --type profilable-command <section> or lvm  dumpconfig  --file  <Pro‐
              fileName.profile>  --type  profilable-metadata  <section> can be used to generate a
              configuration with profilable settings in either of the type for given section  and
              save it to new ProfileName.profile (if the section is not specified, all profilable
              settings are reported).

              The profiles are stored in /etc/lvm/profile directory by  default.   This  location
              can be changed by using the config/profile_dir setting.  Each profile configuration
              is stored in ProfileName.profile file in the profile  directory.  When  referencing
              the profile, the .profile suffix is left out.

       tag config
              See tags configuration setting description below.

       When  several  configuration  methods are used at the same time and when LVM looks for the
       value of a particular setting, it traverses this config cascade from left to right:

       direct config override on command line -> command profile config -> metadata profile  con‐
       fig -> tag config -> lvm.conf

       No part of this cascade is compulsory. If there's no setting value found at the end of the
       cascade, a default value is used for that setting.  Use lvm dumpconfig to check what  set‐
       tings are in use and what the default values are.

       This section describes the configuration file syntax.

       Whitespace  is not significant unless it is within quotes.  This provides a wide choice of
       acceptable indentation styles.  Comments begin with # and continue to the end of the line.
       They are treated as whitespace.

       Here is an informal grammar:

       file = value*
              A configuration file consists of a set of values.

       value = section | assignment
              A value can either be a new section, or an assignment.

       section = identifier '{' value* '}'
              A section is groups associated values together.
              It is denoted by a name and delimited by curly brackets.
              e.g. backup {

       assignment = identifier '=' ( array | type )
              An assignment associates a type with an identifier.
              e.g. level = 7

       array =  '[' ( type ',')* type ']' | '[' ']'
              Inhomogeneous arrays are supported.
              Elements must be separated by commas.
              An empty array is acceptable.

       type = integer | float | string
              integer = [0-9]*
              float = [0-9]*'.'[0-9]*
              string = '"'.*'"'

              Strings must be enclosed in double quotes.

       The sections that may be present in the file are:

       devices — Device settings

              dir  — Directory in which to create volume group device nodes.  Defaults to "/dev".
              Commands also accept this as a prefix on volume group names.

              scan — List of directories to scan recursively for LVM physical  volumes.   Devices
              in directories outside this hierarchy will be ignored.  Defaults to "/dev".

              preferred_names  — List of patterns compared in turn against all the pathnames ref‐
              erencing the same device in in the scanned directories.  The pathname that  matches
              the  earliest pattern in the list is the one used in any output.  As an example, if
              device-mapper multipathing is used, the  following  will  select  multipath  device
              devices { preferred_names = [ "^/dev/mapper/mpath" ] }

              filter  — List of patterns to apply to devices found by a scan.  Patterns are regu‐
              lar expressions delimited by any character and preceded by a (for accept) or r (for
              reject).   The  list is traversed in order, and the first regex that matches deter‐
              mines if the device will be accepted or rejected  (ignored).   Devices  that  don't
              match  any  patterns are accepted. If you want to reject patterns that don't match,
              end the list with "r/.*/".  If there are several names for the  same  device  (e.g.
              symbolic  links  in /dev), if the first matching pattern in the list for any of the
              names is an a pattern, the device is accepted; otherwise if the first matching pat‐
              tern  in the list for any of the names is an r pattern it is rejected; otherwise it
              is accepted.  As an example, to ignore /dev/cdrom you could use:
              devices { filter=["r|cdrom|"] }

              global_filter — Since "filter" might get overridden from the command  line,  it  is
              not  suitable  for  system-wide  device  filtering  (udev  rules, lvmetad). To hide
              devices from LVM-specific udev processing and/or from  lvmetad,  you  need  to  set
              global_filter.  The  syntax  is the same as for normal "filter" above. Devices that
              fail the global_filter are not even opened by LVM.

              cache_dir — Persistent filter cache file directory.  Defaults to "/etc/lvm/cache".

              write_cache_state — Set to 0 to disable the writing out of  the  persistent  filter
              cache file when lvm exits.  Defaults to 1.

              types  —  List  of  pairs  of  additional  acceptable  block  device types found in
              /proc/devices together with maximum (non-zero) number of partitions (normally  16).
              By  default,  LVM2  supports ide, sd, md, loop, dasd, dac960, nbd, ida, cciss, ubd,
              ataraid, drbd, power2, i2o_block and iseries/vd.  Block devices with major  numbers
              of  different  types  are ignored by LVM2.  Example: types = ["fd", 16].  To create
              physical volumes on device-mapper volumes created outside LVM2,  perhaps  encrypted
              ones  from  cryptsetup,  you'll  need types = ["device-mapper", 16].  But if you do
              this, be careful to avoid recursion within LVM2.  The figure for number  of  parti‐
              tions is not currently used in LVM2 - and might never be.

              sysfs_scan  —  If  set to 1 and your kernel supports sysfs and it is mounted, sysfs
              will be used as a quick way of filtering out block devices that are not present.

              md_component_detection — If set to 1, LVM2 will ignore devices used  as  components
              of  software  RAID  (md) devices by looking for md superblocks. This doesn't always
              work satisfactorily e.g. if  a  device  has  been  reused  without  wiping  the  md
              superblocks first.

              md_chunk_alignment  — If set to 1, and a Physical Volume is placed directly upon an
              md device, LVM2 will align its data blocks with the md device's stripe-width.

              data_alignment_detection — If set to 1, and your kernel provides topology  informa‐
              tion  in sysfs for the Physical Volume, the start of data area will be aligned on a
              multiple of the ’minimum_io_size’ or ’optimal_io_size’  exposed  in  sysfs.   mini‐
              mum_io_size  is  the  smallest  request  the device can perform without incurring a
              read-modify-write penalty (e.g. MD's chunk size).  optimal_io_size is the  device's
              preferred  unit of receiving I/O (e.g. MD's stripe width).  minimum_io_size is used
              if optimal_io_size is undefined (0).  If both  md_chunk_alignment  and  data_align‐
              ment_detection are enabled the result of data_alignment_detection is used.

              data_alignment  —  Default  alignment (in KB) of start of data area when creating a
              new Physical Volume using the lvm2 format.  If a Physical Volume is placed directly
              upon  an  md  device  and md_chunk_alignment or data_alignment_detection is enabled
              this parameter is ignored.  Set to 0 to use the default alignment of  64KB  or  the
              page size, if larger.

              data_alignment_offset_detection  —  If  set to 1, and your kernel provides topology
              information in sysfs for the Physical Volume, the start of the aligned data area of
              the Physical Volume will be shifted by the alignment_offset exposed in sysfs.

              To see the location of the first Physical Extent of an existing Physical Volume use
              pvs -o +pe_start .  It will be a multiple of the requested data_alignment plus  the
              alignment_offset  from data_alignment_offset_detection (if enabled) or the pvcreate

              disable_after_error_count — During each LVM operation  errors  received  from  each
              device  are  counted.   If the counter of a particular device exceeds the limit set
              here, no further I/O is sent to that device for the  remainder  of  the  respective
              operation. Setting the parameter to 0 disables the counters altogether.

              pv_min_size  —  Minimal size (in KB) of the block device which can be used as a PV.
              In clustered environment all nodes have to use the same value.  Any  value  smaller
              than  512KB  is  ignored.  Up to and include version 2.02.84 the default was 512KB.
              From 2.02.85 onwards it was changed to 2MB to avoid floppy drives by default.

              issue_discards — Issue discards to a logical  volumes's  underlying  physical  vol‐
              ume(s) when the logical volume is no longer using the physical volumes' space (e.g.
              lvremove, lvreduce, etc).  Discards inform the storage that a region is  no  longer
              in  use.   Storage  that supports discards advertise the protocol specific way dis‐
              cards should be issued by the kernel (TRIM, UNMAP, or WRITE  SAME  with  UNMAP  bit
              set).   Not  all  storage will support or benefit from discards but SSDs and thinly
              provisioned LUNs generally do.  If set to 1, discards will only be issued  if  both
              the storage and kernel provide support.

       allocation — Space allocation policies

              cling_tag_list — List of PV tags matched by the cling allocation policy.

              When  searching  for  free  space to extend an LV, the cling allocation policy will
              choose space on the same PVs as the last segment of the existing LV.  If  there  is
              insufficient space and a list of tags is defined here, it will check whether any of
              them are attached to the PVs concerned and then seek to match those PV tags between
              existing extents and new extents.

              The @ prefix for tags is required.  Use the special tag "@*" as a wildcard to match
              any PV tag and so use all PV tags for this purpose.

              For example, LVs are mirrored between two sites within a single VG.  PVs are tagged
              with  either  @site1 or @site2 to indicate where they are situated and these two PV
              tags are selected for use with this allocation policy:

              cling_tag_list = [ "@site1", "@site2" ]

       log — Default log settings

              file — Location of log file.  If this entry is not present, no log file is written.

              overwrite — Set to 1 to overwrite the log file each time a  tool  is  invoked.   By
              default tools append messages to the log file.

              level — Log level (0-9) of messages to write to the file.  9 is the most verbose; 0
              should produce no output.

              verbose — Default level (0-3) of messages sent to stdout or stderr.  3 is the  most
              verbose; 0 should produce the least output.

              silent — Set to 1 to suppress all non-essential tool output.  When set, display and
              reporting tools will still write the requested device properties to  standard  out‐
              put,  but  messages confirming that something was or wasn't changed will be reduced
              to the 'verbose' level and not appear unless -v is supplied.

              syslog — Set to 1 (the default) to send log messages through syslog.  Turn  off  by
              setting  to  0.   If you set to an integer greater than one, this is used - unvali‐
              dated - as the facility.  The default is LOG_USER.   See  /usr/include/sys/syslog.h
              for safe facility values to use.  For example, LOG_LOCAL0 might be 128.

              indent  —  When  set  to  1  (the default) messages are indented according to their
              severity, two spaces per level.  Set to 0 to turn off indentation.

              command_names — When set to 1, the command name is used as a prefix for  each  mes‐
              sage.  Default is 0 (off).

              prefix  —  Prefix  used  for all messages (after the command name).  Default is two

              activation — Set to 1 to log messages while devices are  suspended  during  activa‐
              tion.   Only  set  this temporarily while debugging a problem because in low memory
              situations this setting can cause your machine to lock up.

       backup — Configuration for metadata backups.

              archive_dir — Directory used for automatic metadata  archives.   Backup  copies  of
              former metadata for each volume group are archived here.  Defaults to "/etc/lvm/ar‐

              backup_dir — Directory used for automatic metadata backups.  A single  backup  copy
              of  the  current  metadata  for  each  volume  group  is  stored here.  Defaults to

              archive — Whether or not tools automatically archive  existing  metadata  into  ar‐
              chive_dir  before making changes to it.  Default is 1 (automatic archives enabled).
              Set to 0 to disable.  Disabling this might  make  metadata  recovery  difficult  or
              impossible if something goes wrong.

              backup — Whether or not tools make an automatic backup into backup_dir after chang‐
              ing metadata.  Default is 1 (automatic backups enabled).   Set  to  0  to  disable.
              Disabling  this  might  make metadata recovery difficult or impossible if something
              goes wrong.

              retain_min — Minimum number of archives to keep.  Defaults to 10.

              retain_days — Minimum number of days to keep archive files.  Defaults to 30.

       shell — LVM2 built-in readline shell settings

              history_size — Maximum number of lines of shell history to retain (default 100)  in

       global — Global settings

              test  — If set to 1, run tools in test mode i.e. no changes to the on-disk metadata
              will get made.  It's equivalent to having the -t option on every command.

              activation — Set to 0 to turn off all communication with the device-mapper  driver.
              Useful if you want to manipulate logical volumes while device-mapper is not present
              in your kernel.

              proc — Mount point of proc filesystem.  Defaults to /proc.

              umask — File creation mask for any files and directories created.   Interpreted  as
              octal  if  the first digit is zero.  Defaults to 077.  Use 022 to allow other users
              to read the files by default.

              format — The default value of --metadatatype used  to  determine  which  format  of
              metadata to use when creating new physical volumes and volume groups. lvm1 or lvm2.

              fallback_to_lvm1  — Set this to 1 if you need to be able to switch between 2.4 ker‐
              nels using LVM1 and kernels including device-mapper.   The  LVM2  tools  should  be
              installed as normal and the LVM1 tools should be installed with a .lvm1 suffix e.g.
              vgscan.lvm1.  If an LVM2 tool is then run but unable to  communicate  with  device-
              mapper, it will automatically invoke the equivalent LVM1 version of the tool.  Note
              that for LVM1 tools to manipulate physical volumes and  volume  groups  created  by
              LVM2 you must use --metadataformat lvm1 when creating them.

              library_dir  — A directory searched for LVM2's shared libraries ahead of the places
              dlopen (3) searches.

              format_libraries — A list of shared libraries to load that contain code to  process
              different  formats of metadata. For example, liblvm2formatpool.so is needed to read
              GFS pool metadata if LVM2 was configured --with-pool=shared.

              locking_type — What type of locking to use.  1 is the default, which use flocks  on
              files in locking_dir (see below) to avoid conflicting LVM2 commands running concur‐
              rently on a single machine. 0 disables locking and risks corrupting your  metadata.
              If  set to 2, the tools will load the external locking_library (see below).  If the
              tools were configured --with-cluster=internal (the default) then  3  means  to  use
              built-in  cluster-wide locking.  Type 4 enforces read-only metadata and forbids any
              operations that might want to modify Volume Group metadata.  All changes to logical
              volumes and their states are communicated using locks.

              wait_for_locks  — When set to 1, the default, the tools wait if a lock request can‐
              not be satisfied immediately.  When set to 0, the operation is aborted instead.

              locking_dir — The directory LVM2 places its file locks if locking_type is set to 1.
              The default is /var/lock/lvm.

              locking_library  — The name of the external locking library to load if locking_type
              is set to 2.  The default is liblvm2clusterlock.so.  If you need to  write  such  a
              library, look at the lib/locking source code directory.

              use_lvmetad  — Whether to use (trust) a running instance of lvmetad. If this is set
              to 0, all commands fall back to the usual scanning mechanisms. When set  to  1  and
              when  lvmetad is running (it is not auto-started), the volume group metadata and PV
              state flags are obtained from the lvmetad instance and no scanning is done  by  the
              individual commands. In a setup with lvmetad, lvmetad udev rules must be set up for
              LVM to work correctly. Without proper udev rules, all changes in block device  con‐
              figuration will be ignored until a manual 'pvscan --cache' is performed.
              If  lvmetad  has  been  running  while use_lvmetad was 0, it MUST be stopped before
              changing use_lvmetad to 1 and started again afterwards.

       tags — Host tag settings

              hosttags — If set to 1, create a host tag with the machine name.  Setting this to 0
              does  nothing,  neither  creating nor destroying any tag.  The machine name used is
              the nodename as returned by uname (2).

              Additional host tags to be set can be listed here as subsections.  The @ prefix for
              tags is optional.  Each of these host tag subsections can contain a host_list array
              of host names. If any one of these entries matches the machine  name  exactly  then
              the host tag gets defined on this particular host, otherwise it doesn't.

              After  lvm.conf  has been processed, LVM2 works through each host tag that has been
              defined in turn, and if there is a configuration file called lvm_<host_tag>.conf it
              attempts  to load it.  The activation/volume_list, devices/filter and devices/types
              settings are merged (these all are lists), otherwise any settings read in  override
              settings  found  in earlier files. Any additional host tags defined get appended to
              the search list, so in turn they can lead to further configuration files being pro‐
              cessed.  Use lvm dumpconfig to check the result of config file processing.

              The  following example always sets host tags tag1 and sets tag2 on machines fs1 and

              tags { tag1 { } tag2 { host_list = [ "fs1", "fs2" ] } }

              These options are useful if you are replicating configuration files around a  clus‐
              ter.   Use  of hosttags = 1 means every machine can have static and identical local
              configuration files yet use different settings and activate different logical  vol‐
              umes by default.  See also volume_list below and --addtag in lvm (8).

       activation — Settings affecting device-mapper activation

              missing_stripe_filler  —  When  activating  an incomplete logical volume in partial
              mode, this option dictates how the missing data is replaced.  A  value  of  "error"
              will  cause  activation to create error mappings for the missing data, meaning that
              read access to missing portions of the volume will result in I/O  errors.  You  can
              instead  also use a device path, and in that case this device will be used in place
              of missing stripes. However, note that using anything other than "error" with  mir‐
              rored  or snapshotted volumes is likely to result in data corruption.  For instruc‐
              tions on how to create a device that always returns zeros, see lvcreate (8).

              mirror_region_size — Unit size in KB for copy operations when mirroring.

              readahead — Used when there is no readahead value stored in the volume group  meta‐
              data.   Set  to none to disable readahead in these circumstances or auto to use the
              default value chosen by the kernel.

              reserved_memory, reserved_stack — How many KB to reserve for LVM2 to use while log‐
              ical  volumes are suspended.  If insufficient memory is reserved before suspension,
              there is a risk of machine deadlock.

              process_priority — The nice value to use while devices are suspended.  This is  set
              to  a  high  priority  so that logical volumes are suspended (with I/O generated by
              other processes to those logical volumes getting queued) for the shortest  possible

              volume_list  — This acts as a filter through which all requests to activate a logi‐
              cal volume on this machine are passed.  A logical volume is only  activated  if  it
              matches  an  item  in the list.  Tags must be preceded by @ and are checked against
              all tags defined in the logical volume and volume group metadata for a  match.   @*
              is short-hand to check every tag set on the host machine (see tags above).  Logical
              volume and volume groups can also be included  in  the  list  by  name  e.g.  vg00,
              vg00/lvol1.   If  this  setting is not present but at least one host tag is defined
              then a default single-entry list containing @* is assumed.

              auto_activation_volume_list — This acts as a filter through which all  requests  to
              autoactivate  a  logical  volume  on  this  machine are passed. A logical volume is
              autoactivated if it matches an item in the list. Volumes must also  pass  the  vol‐
              ume_list filter, if present. Tags must be preceded by @ and are checked against all
              tags defined in the logical volume and volume group metadata for  a  match.  @*  is
              short-hand  to  check  every tag set on the host machine (see tags above).  Logical
              volume and volume groups can also be included  in  the  list  by  name  e.g.  vg00,

              read_only_volume_list  —  This acts as a filter through which all requests to acti‐
              vate a logical volume on this machine are passed.  A logical volume is activated in
              read-only  mode (instead of read-write) if it matches an item in the list.  Volumes
              must first pass the volume_list filter, if present.  Tags must be preceded by @ and
              are  checked  against all tags defined in the logical volume and volume group meta‐
              data for a match.  @* is short-hand to check every tag set on the host machine (see
              tags  above).  Logical volume and volume groups can also be included in the list by
              name e.g. vg00, vg00/lvol1.

       metadata — Advanced metadata settings

              pvmetadatacopies — When creating a physical volume using the LVM2 metadata  format,
              this  is the default number of copies of metadata to store on each physical volume.
              Currently it can be set to 0, 1 or 2.  The default is 1.  If set to 2, one copy  is
              placed  at the beginning of the disk and the other is placed at the end.  It can be
              overridden on the command line with --pvmetadatacopies (see pvcreate).  If creating
              a  volume  group  with just one physical volume, it's a good idea to have 2 copies.
              If creating a large volume group with many physical volumes, you may decide that  3
              copies of the metadata is sufficient, i.e. setting it to 1 on three of the physical
              volumes, and 0 on the rest.  Every volume group must contain at least one  physical
              volume  with at least 1 copy of the metadata (unless using the text files described
              below).  The disadvantage of having lots of copies is that  every  time  the  tools
              access  the  volume  group, every copy of the metadata has to be accessed, and this
              slows down the tools.

              pvmetadatasize — Approximate number of sectors to set aside for each  copy  of  the
              metadata.  Volume groups with large numbers of physical or logical volumes, or vol‐
              umes groups containing complex logical volume structures will need additional space
              for  their metadata.  The metadata areas are treated as circular buffers, so unused
              space becomes filled with an archive of the most recent previous  versions  of  the

              pvmetadataignore  When  creating  a physical volume using the LVM2 metadata format,
              this states whether metadata areas should be ignored.   The  default  is  "n".   If
              metadata areas on a physical volume are ignored, LVM will not not store metadata in
              the metadata areas present on newly created Physical Volumes.  The  option  can  be
              overridden  on  the command line with --metadataignore (See pvcreate and pvchange).
              Metadata areas cannot be created or extended after Logical Volumes have been  allo‐
              cated  on  the  device.  If you do not want to store metadata on this device, it is
              still wise always to allocate a metadata area (use a non-zero value  for  --pvmeta‐
              datacopies)  in  case  you need it in the future and to use this option to instruct
              LVM2 to ignore it.

              vgmetadatacopies — When creating a volume group using  the  LVM2  metadata  format,
              this  is  the  default number of copies of metadata desired across all the physical
              volumes in the volume group.  If set to a non-zero value,  LVM  will  automatically
              set  or  clear  the  metadataignore  flag on the physical volumes (see pvcreate and
              pvchange --metadataignore) in order to  achieve  the  desired  number  of  metadata
              copies.   An  LVM command that adds or removes physical volumes (for example, vgex‐
              tend, vgreduce, vgsplit, or vgmerge), may cause LVM to automatically set  or  clear
              the  metadataignore  flags.  Also, if physical volumes go missing or reappear, or a
              new number of copies is explicitly set (see vgchange --vgmetadatacopies),  LVM  may
              adjust  the  metadataignore  flags.  Set vgmetadatacopies to 0 instructs LVM not to
              set or clear the metadataignore flags automatically.  You may set  a  value  larger
              than the sum of all metadata areas on all physical volumes.  The value can be over‐
              ridden on the command line with --vgmetadatacopies for various commands (for  exam‐
              ple,  vgcreate  and  vgchange), and can be queryied with the vg_mda_copies field of
              vgs.  This 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 over‐

              dirs — List of directories holding live copies of  LVM2  metadata  as  text  files.
              These  directories must not be on logical volumes.  It is possible to use LVM2 with
              a couple of directories here, preferably on different (non-logical-volume) filesys‐
              tems and with no other on-disk metadata, pvmetadatacopies = 0.  Alternatively these
              directories can be in addition to the on-disk metadata  areas.   This  feature  was
              created during the development of the LVM2 metadata before the new on-disk metadata
              areas were designed and no longer gets tested.  It is not supported under  low-mem‐
              ory  conditions,  and it is important never to edit these metadata files unless you
              fully understand how things work: to make changes you should always use  the  tools
              as normal, or else vgcfgbackup, edit backup, vgcfgrestore.


       lvm(8), umask(2), uname(2), dlopen(3), syslog(3), syslog.conf(5)

Sistina Software UK             LVM TOOLS 2.02.111(2) (2014-09-01)                    LVM.CONF(5)

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