Ubuntu Manpage: lvm.conf — Configuration file for LVM2

Provided by: lvm2_2.02.176-4.1ubuntu3.18.04.3_amd64

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.

For a description of each lvm.conf setting, run:

lvmconfig --typeconfig default --withcomments --withspaces

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

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 configuration. 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 profiles.

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 profile 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/Logical 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 profiles.

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_template.profile (for
metadata profiles) which contain all settings that are customizable by profiles of certain type.
Users are encouraged to copy these template profiles and edit them as needed. Alternatively, the
lvmconfig --file <ProfileName.profile> --type profilable-command <section> or lvmconfig --file
<ProfileName.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 config-> tag config->
lvmlocal.conf-> 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 lvmconfig to check what settings are in use and what the
default values are.

SYNTAX

       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 groups associated values together. If the same section is  encountered  multiple  times,
              the contents of all instances are concatenated together in the order of appearance.
              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. If the identifier contains forward slashes,
              those are interpreted as path delimiters. The statement  section/key  =  value  is  equivalent  to
              section  {  key  =  value  }. If multiple instances of the same key are encountered, only the last
              value is used (and a warning is issued).
              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 with spaces must be enclosed in double quotes, single words that start with a  letter  can
              be left unquoted.

SETTINGS

       The  lvmconfig  command  prints  the  LVM  configuration  settings  in  various  ways.   See the man page
       lvmconfig(8).

       Command to print a list of all possible config settings, with their default values:
       lvmconfig --type default

       Command to print a list of  all  possible  config  settings,  with  their  default  values,  and  a  full
       description of each as a comment:
       lvmconfig --type default --withcomments

       Command  to  print  a  list  of all possible config settings, with their current values (configured, non-
       default values are shown):
       lvmconfig --type current

       Command to print all config settings that have been configured with a different value  than  the  default
       (configured, non-default values are shown):
       lvmconfig --type diff

       Command to print a single config setting, with its default value, and a full description, where "Section"
       refers to the config section, e.g. global, and "Setting" refers to the name of the specific setting, e.g.
       umask:
       lvmconfig --type default --withcomments Section/Setting

FILES