lvm.conf man page on YellowDog

Man page or keyword search:  
man Server   18644 pages
apropos Keyword Search (all sections)
Output format
YellowDog logo
[printable version]

LVM.CONF(5)							   LVM.CONF(5)

NAME
       lvm.conf - Configuration file for LVM2

SYNOPSIS
       /etc/lvm/lvm.conf

DESCRIPTION
       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 reloaded.

       Use lvm dumpconfig to check what settings are in use.

SYNTAX
       This section describes the configuration file syntax.

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

       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. max_archives = 42

       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.

SECTIONS
       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 referencing 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 names:
	      devices { preferred_names = [ "^/dev/mapper/mpath" ] }

	      filter — List of patterns to apply to devices found by  a	 scan.
	      Patterns	are regular expressions delimited by any character and
	      preceded by a (for accept) or r (for reject).  The list is  tra‐
	      versed  in order, and the first regex that matches determines 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	 any  name  matches  any  a  pattern,  the  device  is
	      accepted;	 otherwise  if	any  name  matches any r pattern it is
	      rejected; otherwise it is accepted.  As an  example,  to	ignore
	      /dev/cdrom you could use:
	      devices { filter=["r|cdrom|"] }

	      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 crypt‐
	      setup, you'll need types = ["device-mapper", 16].	 But if you do
	      this, be careful to avoid recursion within LVM2.	The figure for
	      number  of  partitions is not currently used in LVM2 - and might
	      never be.

	      sysfs_scan (em 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 (em 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.

       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  out‐
	      put.

	      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 - unvalidated - 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 message.	Default is 0 (off).

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

	      activation  —  Set  to  1 to log messages while devices are sus‐
	      pended during  activation.   Only	 set  this  temporarily	 while
	      debugging	 a  problem because in low memory situations this set‐
	      ting 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/archive".

	      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 "/etc/lvm/backup".

	      archive — Whether or not tools  automatically  archive  existing
	      metadata	into archive_dir before making changes to it.  Default
	      is 1 (automatic archives enabled).  Set to 0 to  disable.	  Dis‐
	      abling 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	 changing  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 $HOME/.lvm_history

       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 cre‐
	      ated.   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 vol‐
	      umes and volume groups. lvm1 or lvm2.

	      fallback_to_lvm1 — Set this to 1 if  you	need  to  be  able  to
	      switch  between  2.4  kernels  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 communi‐
	      cate with device-mapper, it will automatically invoke the equiv‐
	      alent 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 con‐
	      tain 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  concurrently	 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=inter‐
	      nal (the default) then 3	means  to  use	built-in  cluster-wide
	      locking.	 All  changes  to logical volumes and their states are
	      communicated using locks.

	      locking_dir — The directory LVM2 places its file locks if	 lock‐
	      ing_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  liblvm2clus‐
	      terlock.so.   If	you  need to write such a library, look at the
	      lib/locking source code directory.

       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 subsec‐
	      tions.  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 configura‐
	      tion file called lvm_<host_tag>.conf it  attempts	 to  load  it.
	      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 processed.	Use lvm dumpconfig to check the result of con‐
	      fig file processing.

	      The  following  example always sets host tags tag1 and sets tag2
	      on machines fs1 and fs2:

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

	      These options are useful if you  are  replicating	 configuration
	      files around a cluster.  Use of hosttags = 1 means every machine
	      can have static and identical local configuration files yet  use
	      different	 settings  and	activate  different logical volumes 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 mirrored or
	      snapshotted volumes is likely to result in data corruption.  For
	      instructions  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 metadata.  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 logical volumes are suspended.  If insuffi‐
	      cient memory is reserved before suspension, there is a  risk  of
	      machine deadlock.

	      process_priority	— The nice value to use while devices are sus‐
	      pended.  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 time.

	      volume_list — This acts as a filter through which	 all  requests
	      to activate a logical volume on this machine are passed.	A log‐
	      ical 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.

       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  --meta‐
	      datacopies.   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 meta‐
	      data 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 volumes groups  containing  com‐
	      plex  logical  volume  structures will need additional space for
	      their metadata.  The metadata areas are treated as circular buf‐
	      fers, so unused space becomes filled with an archive of the most
	      recent previous versions of the metadata.

	      dirs — List of directories holding live copies of LVM2  metadata
	      as  text	files.	 These directories must not be on logical vol‐
	      umes.  It is possible to use LVM2 with a couple  of  directories
	      here,  preferably	 on different (non-logical-volume) filesystems
	      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 devel‐
	      opment  of  the  LVM2  metadata  before the new on-disk metadata
	      areas were designed and no longer gets tested.  It is  not  sup‐
	      ported under low-memory 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.

FILES
       /etc/lvm/lvm.conf	   /etc/lvm/archive	       /etc/lvm/backup
       /etc/lvm/cache/.cache /var/lock/lvm

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

Sistina Software UK		   LVM TOOLS			   LVM.CONF(5)
[top]

List of man pages available for YellowDog

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net