Provided by: lvm2_2.03.07-1ubuntu1_amd64 bug

NAME

       lvmreport — LVM reporting and related features

DESCRIPTION

       LVM  uses single reporting infrastructure that sets standard on LVM command's output and it provides wide
       range of configuration settings and command line options to customize  report  and  filter  the  report's
       output.

Categorization based on reporting facility

       Based  on  functionality,  commands  which  make  use  of the reporting infrastructure are divided in two
       groups:

       Report-oriented
              These commands inform about  current  LVM  state  and  their  primary  role  is  to  display  this
              information  in  compendious  way. To make a distinction, we will name this report as main report.
              The set of report-only commands include: pvs,  vgs,  lvs,  pvdisplay,  vgdisplay,  lvdisplay,  lvm
              devtypes, lvm fullreport.  For further information about main report, see main report specifics.

       Processing-oriented
              These  commands  are responsible for changing LVM state and they do not contain any main report as
              identified for report-oriented commands, they only perform some kind of  processing.  The  set  of
              processing-oriented commands includes: pvcreate, vgcreate, lvcreate, pvchange, vgchange, lvchange,
              pvremove,  vgremove,  lvremove,  pvresize,  vgextend,  vgreduce,  lvextend,  lvreduce,   lvresize,
              lvrename,  pvscan,  vgscan,  lvscan,  pvmove,  vgcfgbackup,  vgck,  vgconvert, vgexport, vgimport,
              vgmknodes.

       If enabled, so called log report is either displayed solely  (for  processing-oriented  commands)  or  in
       addition  to  main  report  (for  report-oriented commands). The log report contains a log of operations,
       messages and  per-object  status  with  complete  object  identification  collected  during  LVM  command
       execution. See log report specifics for more information about this report type.

Terms

       When  describing  reporting functionality and features in this text, we will use terms row and column. By
       row we mean series of values reported for single entity (for example single PV, VG  or  LV).  Each  value
       from  the  row then belongs to a column of certain type. The columns have column headings which are short
       descriptions for the columns. The columns are referenced by column names. Please note that this  text  is
       also  using  term  field  interchangeably  with  the  term  column.  Most of the time the term columns is
       abbreviated as col in configuration.

Common report configuration settings and command line options

       There are common configuration settings and command line options which apply to both main report and  log
       report. Following lists contain all of them, separated into groups based on their use.

              Common configuration settings:

                     •  Changing report output format, composition and other output modifiers:

                        -  global/units

                        -  global/suffix

                        -  report/output_format

                        -  report/compact_output

                        -  report/compact_output_cols

                        -  report/aligned

                        -  report/headings

                        -  report/separator

                        -  report/list_item_separator

                        -  report/prefixes

                        -  report/quoted

                        -  report/columns_as_rows

                        -  report/binary_values_as_numeric

                        -  report/time_format

                        -  report/mark_hidden_devices

                        -  report/two_word_unknown_device

                     •  Special settings

                        -  report/buffered

       This  document  does  not  describe  these  settings  in  more detail - if you need detailed information,
       including values which are accepted for the settings, please run lvmconfig --type default  --withcomments
       <setting>. There are more configuration settings in addition to the common set listed above, but they are
       specific to either main report or log report, see main report specifics  and  log  report  specifics  for
       these  settings.  Besides  configuring  reports  globally by using configuration settings, there are also
       command line options you can use to extend, override or further specify the report configuration.

              Common command line options:

                     •  Definition of the set set of fields to use

                        -  --options|-o FieldSet
                           Field set to use. See main report specifics and log report specifics for  information
                           about  field  sets  configured  with  global  configuratin  settings that this option
                           overrides.

                        -  --options|-o+ FieldSet
                           Fields to include to current field set. See  main  report  specifics and  log  report
                           specifics  for  information  about  field  sets  configured with global configuration
                           settings that this option extends.

                        -  --options|-o- FieldSet
                           Fields to exclude from current field set. See main report specifics  and  log  report
                           specifics  for  information  about  field  sets  configured with global configuration
                           settings that this option reduces.

                        -  --options|-o# FieldSet
                           Compaction  of  unused  fields.  Overrides  report/compact_output_cols  configuration
                           setting.

                     •  Sorting

                        -  --sort|-O+ FieldSet
                           Fields  to  sort  by  in  ascending  order.  See main report specifics and log report
                           specifics for information about  field  sets  configured  with  global  configuration
                           settings that this option overrides.

                        -  --sort|-O- FieldSet
                           Fields  to  sort  by  in  descending  order. See main report specifics and log report
                           specifics for information about fields  sets  configured  with  global  configuration
                           settings that this options overrides.

                     •  Selection

                        -  --select|-S Selection
                           Define  selection  criteria  for  report  output. For log report, this also overrides
                           log/command_log_selection configuration setting, see also log report specifics.

                     •  Changing output format and composition

                        -  --reportformat
                           Overrides report/output_format configuration setting.

                        -  --aligned
                           Overrides report/aligned configuration setting.

                        -  --binary
                           Overrides report/binary_values_as_numeric configuration setting.

                        -  --nameprefixes
                           Overrides report/prefixes configuration setting.

                        -  --noheadings
                           Overrides report/noheadings configuration setting.

                        -  --nosuffix
                           Overrides global/suffix configuration setting.

                        -  --rows
                           Overrides report/columns_as_rows configuration setting.

                        -  --separator
                           Overrides report/separator configuration setting.

                        -  --units
                           Overrides global/units configuration setting.

                        -  --unquoted
                           Overrides report/quoted configuration setting.

                     •  Special options

                        -  --configreport ReportName
                           This defines the  ReportName  for  which  any  subsequent  -o--columns,  -O--sort  or
                           -S--select  applies  to.  See also main report specifics and log report specifics for
                           possible ReportName values.

                        -  --logonly
                           When an LVM command contains both main report and log report, this option  suppresses
                           the main report output and it causes the log report output to be displayed only.

                        -  --unbuffered
                           Overrides report/bufffered configuration setting.

       The  FieldSet  mentioned in the lists above is a set of field names where each field name is delimited by
       "," character. Field set definition, sorting and selection may  be  repeated  on  command  line  (-o+/-o-
       includes/excludes fields to/from current list, for all the other repeatable options, the last value typed
       for the option on the command line is used). The Selection is a string with selection criteria, see  also
       Selection paragraph below for more information about constructing these criteria.

Main report specifics

       The  main  report currently encompasses these distinct subtypes, referenced by their name - ReportName as
       listed below. The command in parenthesis is representative command that uses the main report  subtype  by
       default.   Each subtype has its own configuration setting for global field set definition as well as sort
       field definition (listed below each individual ReportName):

              •  pv representing report about Physical Volumes (pvs)

                 -  report/pvs_cols

                 -  report/pvs_sort

              •  pvseg representing report about Physical Volume Segments (pvs --segments)

                 -  report/pvseg_cols

                 -  report/pvseg_sort

              •  vg representing report about Volume Groups (vgs)

                 -  report/vgs_cols

                 -  report/vgs_sort

              •  lv representing report about Logical Volumes (lvs)

                 -  report/lvs_cols

                 -  report/lvs_sort

              •  seg representing report about Logical Volume Segments (lvs --segments)

                 -  report/segs_cols

                 -  report/segs_sort

              •  full representing report combining all of the above as a whole (lvm fullreport)

                 -  report/pvs_cols_full

                 -  report/pvs_sort_full

                 -  report/pvsegs_cols_full

                 -  report/pvseg_sort_full

                 -  report/vgs_cols_full

                 -  report/vgs_sort_full

                 -  report/lvs_cols_full

                 -  report/lvs_sort_full

                 -  report/segs_cols_full

                 -  report/segs_sort_full

              •  devtype representing report about device types (lvm devtypes)

                 -  report/devtypes_cols

                 -  report/devtypes_sort

       Use pvs, vgs, lvs -o help or lvm devtypes -o help to get complete list of fields that  you  can  use  for
       main report. The list of fields in the help output is separated in groups based on which report type they
       belong to.  Note that LVM can change final report type used if fields from different groups are  combined
       together. Some of these combinations are not allowed in which case LVM will issue an error.

       For  all  main report subtypes except full, it's not necessary to use --configreport ReportName to denote
       which report any subsequent -o, -O or -S option applies to as they always apply to the single main report
       type.  Currently,  lvm  fullreport  is  the only command that includes more than one main report subtype.
       Therefore, the --configreport is particularly suitable for the full report if you need to configure  each
       of its subreports in a different way.

Log report specifics

       You  can  enable  log  report  with  log/report_command_log configuration setting - this functionality is
       disabled by default. The log report contains a log collected during LVM command execution  and  then  the
       log  is displayed just like any other report known from main report. There is only one log report subtype
       as shown below together with related configuration settings for fields, sorting and selection:

              •  log representing log report

                 -  log/command_log_cols

                 -  log/command_log_sort

                 -  log/command_log_selection

       You always need to use --configreport  log  together  with  -o--options,  -O--sort  or  -S--selection  to
       override configuration settings directly on command line for log report. When compared to main report, in
       addition to usual configuration settings  for  report  fields  and  sorting,  the  log  report  has  also
       configuration option for selection - report/command_log_selection. This configuration setting is provided
       for convenience so it's not necessary to use -S--select on command line  each  time  an  LVM  command  is
       executed and we need the same selection criteria to be applied for log report. Default selection criteria
       used for log report are log/command_log_selection="!(log_type=status &&  message=success)".   This  means
       that,  by  default, log report doesn't display status messages about successful operation and it displays
       only rows with  error,  warning,  print-type  messages  and  messages  about  failure  states  (for  more
       information, see log report content below).

       Log report coverage
       Currently,  when  running  LVM  commands  directly  (not  in  LVM shell), the log report covers command's
       processing stage which is the moment when LVM entities are iterated and processed one by one. It does not
       cover  any  command  initialization nor command finalization stage. If there is any message issued out of
       log report's coverage range, such message goes directly to output, bypassing the log report. By  default,
       that  is  standard  error output for error and warning messages and standard output for common print-like
       messages.

       When running LVM commands in LVM shell,  the  log  report  covers  the  whole  LVM  command's  execution,
       including  command's  processing  as well as initialization and finalization stage. So from this point of
       view, the log report coverage is complete for executed LVM commands. Note that  there  are  still  a  few
       moments  when  LVM  shell  needs  to  initialize  itself  before it even enters the main loop in which it
       executes LVM commands. Also, there is a moment when LVM shell needs to prepare log  report  properly  for
       next  command executed in the shell and then, after the command's run, the shell needs to display the log
       report for that recently executed command. If there is a failure or any other message issued during  this
       time, the LVM will bypass log report and display messages on output directly.

       For  these  reasons  and  for  completeness,  it's  not  possible to rely fully on log report as the only
       indicator of LVM command's status and the only  place  where  all  messages  issued  during  LVM  command
       execution are collected.  You always need to check whether the command has not failed out of log report's
       range by checking the non-report output too.

       To help with this, LVM can separate output which you can then redirect to any custom file descriptor that
       you  prepare  before  running  an  LVM  command  or  LVM  shell  and  then you make LVM to use these file
       descriptors for different kinds of output by defining environment variables with file descriptor numbers.
       See also LVM_OUT_FD, LVM_ERR_FD and LVM_REPORT_FD environment variable description in lvm(8) man page.

       Also  note that, by default, reports use the same file descriptor as common print-like messages, which is
       standard output. If you plan to use log report in your scripts or  any  external  tool,  you  should  use
       LVM_OUT_FD,  LVM_ERR_FD and LVM_REPORT_FD to separate all output types to different file descriptors. For
       example, with bash, that would be:

              LVM_OUT_FD=3 LVM_ERR_FD=4 LVM_REPORT_FD=5 <lvm command> 3>out_file 4>err_file 5>report_file

       Where the <lvm_command> is either direct LVM command or LVM shell.  You can collect all  three  types  of
       output in particular files then.

       Log report content
       Each item in the log report consists of these set of fields providing various information:

              •  Basic information (mandatory):

                 -  log_seq_num
                    Item  sequence  number.  The sequence number is unique for each log item and it increases in
                    the order of the log items as they appeared during LVM command execution.

                 -  log_type
                    Type of log for the item. Currently, these types are used:

                           status for any status information that is logged

                           print for any common message printed while the log is collected

                           error for any error message printed while the log is collected

                           warn for any warning message printed while the log is collected

                 -  log_context
                    Context of the log for the item. Currently, two contexts are identified:

                           shell for the log collected in the outermost code before and after executing concrete
                           LVM commands

                           processing  for  the  log  collected while processing LVM entities during LVM command
                           execution

              •  Message (mandatory):

                 -  log_message
                    Any message associated with current item. For status log type, the message  contains  either
                    success  or failure denoting current state. For print, error and warn log types, the message
                    contains the exact message of that type that got issued.

              •  Object information (used only if applicable):

                 -  log_object_type field
                    Type of the object processed. Currently, these object types are recognized:

                           cmd for command as a whole

                           orphan for processing group of PVs not in any VG yet

                           pv for PV processing

                           label for direct PV label processing (without VG metadata)

                           vg for VG processing

                           lv for LV processing

                 -  log_object_name
                    Name of the object processed.

                 -  log_object_id
                    ID of the object processed.

                 -  log_object_group
                    A group where the processed object belongs to.

                 -  log_object_group_id
                    An ID of a group where the processed object belongs to.

              •  Numeric status (used only if applicable)

                 -  log_errno
                    Error number associated with current item.

                 -  log_ret_code
                    Rreturn code associated with current item.

       You can also run <lvm_command> --configreport log -o help to to display complete list of fields that  you
       may use for the log report.

Selection

       Selection is used for a report to display only rows that match selection criteria. All rows are displayed
       with the additional selected field (-o selected) displaying 1 if the row  matches  the  Selection  and  0
       otherwise.  The  selection  criteria  are a set of statements combined by logical and grouping operators.
       The statement consists of a field name for which a set  of  valid  values  is  defined  using  comparison
       operators.  For  complete  list  of  fields  names  that  you  can  use  in  selection, see the output of
       <lvm_command> -S help. The help output also contains type of values that each field displays enclosed  in
       brackets.

       List of operators recognized in selection criteria

              •  Comparison operators (cmp_op)

                        =~ matching regular expression.

                        !~ not matching regular expression.

                        =  equal to.

                        != not equal to.

                        >= greater than or equal to.

                        >  greater than

                        <= less than or equal to.

                        <  less than.

              •  Binary logical operators (cmp_log)

                        && all fields must match

                        ,  all fields must match

                        || at least one field must match

                        #  at least one field must match

              •  Unary logical operators

                        !  logical negation

              •  Grouping operators

                        (  left parenthesis

                        )  right parenthesis

                        [  list start

                        ]  list end

                        {  list subset start

                        }  list subset end

       Field types and selection operands
       Field  type  restricts  the  set  of  operators  and values that you may use with the field when defining
       selection criteria. You can see field type for each field if you run <lvm command> -S help where you  can
       find the type name enclosed in square brackets. Currently, LVM recognizes these field types in reports:

              •  string  for set of characters (for each string field type, you can use either string or regular
                 expression - regex for the value used in selection criteria)

              •  string list for set of strings

              •  number for integer value

              •  size for integer or floating point number with size unit suffix (see also lvcreate(8) man  page
                 and description for "-L--size" option for the list of recognized suffixes)

              •  percent for floating point number with or without "%" suffix (e.g. 50 or 50%)

              •  time for time values

       When using string list in selection criteria, there are several ways how LVM can match string list fields
       from report, depending on what list grouping operator is used and what item separator is used within that
       set of items. Also, note that order of items does not matter here.

              •  matching the set strictly where all items must match - use [ ], e.g.  ["a","b","c"]

              •  matching a subset of the set - use { } with "," or "&&" as item delimiter, e.g. {"a","b","c"}

              •  matching  an  intersection with the set - use { } with "#" or "||" as item delimiter, e.g. {"a"
                 || "b" || "c"}

       When using time in your selection criteria, LVM  can  recognize  various  time  formats  using  standard,
       absolute  or freeform expressions. For examples demonstrating time expressions in selection criteria, see
       EXAMPLES section.

              •  Standard time format

                 -  date

                           YYYY-MM-DD

                           YYYY-MM, auto DD=1

                           YYYY, auto MM=01 and DD=01

                 -  time

                           hh:mm:ss

                           hh:mm, auto ss=0

                           hh, auto mm=0, auto ss=0

                 -  timezone

                           +hh:mm or -hh:mm

                           +hh or -hh

                 The full date/time specification is YYYY-MM-DD hh:mm:ss. Users  are  able  to  leave  date/time
                 parts  from  right to left. Whenever these parts are left out, a range is assumed automatically
                 with second granularity. For example:

                           "2015-07-07 9:51" means range of "2015-07-07 9:51:00" - "2015-07-07 9:51:59".

                           "2015-07" means range of "2015-07-01 0:00:00" - "2015-07-31 23:59:59"

                           "2015" means range of "2015-01-01 0:00:00" - "2015-12-31 23:59:59"

              •  Absolute time format

                 Absolute time is defined as number of seconds since the Epoch (1970:01:01 00:00 +00:00).

                 -  @seconds

              •  Freeform time format

                 -  weekday names ("Sunday" - "Saturday" or abbreviated as "Sun" - "Sat")

                 -  labels for points in time ("noon", "midnight")

                 -  labels for a day relative to current day ("today", "yesterday")

                 -  points back in time with relative offset from today (N is a number)

                           "N" "seconds" / "minutes" / "hours" / "days" / "weeks" / "years" "ago"

                           "N" "secs" / "mins" / "hrs" ... "ago"

                           "N" "s" / "m" / "h" ... "ago"

                 -  time specification either in hh:mm:ss format or with AM/PM suffixes

                 -  month names ("January" - "December" or abbreviated as "Jan" - "Dec")

       Informal grammar specification

                     STATEMENT = column cmp_op VALUE | STATEMENT log_op STATEMENT | (STATEMENT) | !(STATEMENT)

                     VALUE = [VALUE log_op VALUE]
                     For list-based types: string list. Matches strictly.  The log_op must always be of one type
                     within the whole list value.

                     VALUE = {VALUE log_op VALUE}
                     For list-based types: string list. Matches a subset.  The log_op must always be of one type
                     within the whole list value.

                     VALUE = value
                     For scalar types: number, size, percent, string (or string regex).

EXAMPLES

   Basic usage
       We start  our  examples  with  default  configuration  -  lvmconfig(8)  is  helpful  command  to  display
       configuration  settings  which  are  currently used, including all configuration related to reporting. We
       will use it throughout examples below to display current configuration.

       # lvmconfig --type full global/units global/suffix \
          report/output_format  report/compact_output \
          report/compact_output_cols report/aligned \
          report/headings report/separator \
          report/list_item_separator report/prefixes \
          report/quoted report/columns_as_rows \
          report/binary_values_as_numeric report/time_format \
          report/mark_hidden_devices report/two_word_unknown_device \
          report/buffered
       units="h"
       suffix=1
       output_format="basic"
       compact_output=0
       compact_output_cols=""
       aligned=1
       headings=1
       separator=" "
       list_item_separator=","
       prefixes=0
       quoted=1
       columns_as_rows=0
       binary_values_as_numeric=0
       time_format="%Y-%m-%d %T %z"
       mark_hidden_devices=1
       two_word_unknown_device=0
       buffered=1

       Also, we start with simple LVM layout with two PVs (/dev/sda, /dev/sdb), VG (vg) and two LVs  (lvol0  and
       lvol1)  in  the  VG.  We  display  all possible reports as single commands here, see also pvs(8), vgs(8),
       lvs(8) man pages  for  more  information.  The  field  set  for  each  report  type  is  configured  with
       configuration settings as we already mentioned in main report specifics section in this man page.

       # lvmconfig --type full report/pvs_cols report/pvs_sort \
          report/pvsegs_cols report/pvsegs_sort report/vgs_cols \
          report/vgs_sort report/lvs_cols report/lvs_sort \
          report/segs_cols report/segs_sort
       pvs_cols="pv_name,vg_name,pv_fmt,pv_attr,pv_size,pv_free"
       pvs_sort="pv_name"
       pvsegs_cols="pv_name,vg_name,pv_fmt,pv_attr,pv_size,pv_free,
                    pvseg_start,pvseg_size"
       pvsegs_sort="pv_name,pvseg_start"
       vgs_cols="vg_name,pv_count,lv_count,snap_count,vg_attr,vg_size,vg_free"
       vgs_sort="vg_name"
       lvs_cols="lv_name,vg_name,lv_attr,lv_size,pool_lv,origin,move_pv,
                 mirror_log,copy_percent,convert_lv"
       lvs_sort="vg_name,lv_name"
       segs_cols="lv_name,vg_name,lv_attr,stripes,segtype,seg_size"
       segs_sort="vg_name,lv_name,seg_start"

       # pvs
         PV         VG Fmt  Attr PSize   PFree
         /dev/sda   vg lvm2 a--  100.00m 88.00m
         /dev/sdb   vg lvm2 a--  100.00m 92.00m

       # pvs --segments
         PV         VG Fmt  Attr PSize   PFree  Start SSize
         /dev/sda   vg lvm2 a--  100.00m 88.00m     0     1
         /dev/sda   vg lvm2 a--  100.00m 88.00m     1     1
         /dev/sda   vg lvm2 a--  100.00m 88.00m     2     1
         /dev/sda   vg lvm2 a--  100.00m 88.00m     3    22
         /dev/sdb   vg lvm2 a--  100.00m 92.00m     0     1
         /dev/sdb   vg lvm2 a--  100.00m 92.00m     1     1
         /dev/sdb   vg lvm2 a--  100.00m 92.00m     2    23

       # vgs
         VG #PV #LV #SN Attr   VSize   VFree
         vg   2   2   0 wz--n- 200.00m 180.00m

       # lvs
         LV    VG Attr       LSize Pool Origin Move Log Cpy%Sync Convert
         lvol0 vg -wi-a----- 4.00m
         lvol1 vg rwi-a-r--- 4.00m                      100.00

       # lvs --segments
         LV    VG Attr       #Str Type   SSize
         lvol0 vg -wi-a-----    1 linear 4.00m
         lvol1 vg rwi-a-r---    2 raid1  4.00m

       We  will  use report/lvs_cols and report/lvs_sort configuration settings to define our own list of fields
       to use and to sort by that is different from defaults. You can do this for other reports in  same  manner
       with report/{pvs,pvseg,vgs,seg}_{cols,sort} configuration settings.  Also note that in the example below,
       we don't display the "lv_time" field even though we're using it for sorting - this is allowed.

       # lvmconfig --type full report/lvs_cols report/lvs_sort
       lvs_cols="lv_name,lv_size,origin,pool_lv,copy_percent"
       lvs_sort="-lv_time"

       # lvs
         LV    LSize Origin Pool Cpy%Sync
         lvol1 4.00m             100.00
         lvol0 4.00m

       You can use -o--options command line option to override current configuration directly on command line.

       # lvs -o lv_name,lv_size
         LV    LSize
         lvol1 4.00m
         lvol0 4.00m

       # lvs -o+lv_layout
         LV    LSize Origin Pool Cpy%Sync Layout
         lvol1 4.00m             100.00   raid,raid1
         lvol0 4.00m                      linear

       # lvs -o-origin
         LV    LSize Pool Cpy%Sync
         lvol1 4.00m      100.00
         lvol0 4.00m

       # lvs -o lv_name,lv_size,origin -o+lv_layout -o-origin -O lv_name
         LV    LSize Layout
         lvol0 4.00m linear
         lvol1 4.00m raid,raid1

       You can obtain the same information with single command where all the information about PVs, PV segments,
       LVs  and  LV  segments  are  obtained  per  VG  under  a  single  VG  lock for consistency, see also lvm-
       fullreport(8) man page for more information. The fullreport has its own configuration settings to  define
       field  sets  to  use,  similar  to individual reports as displayed above, but configuration settings have
       "_full" suffix now.  This way, it's possible to configure different sets of fields to display and to sort
       by for individual reports as well as the full report.

       # lvmconfig --type full report/pvs_cols_full \
          report/pvs_sort_full report/pvsegs_cols_full \
          report/pvsegs_sort_full report/vgs_cols_full \
          report/vgs_sort_full report/lvs_cols_full \
          report/lvs_sort_full report/segs_cols_full \
          report/segs_sort_full
       pvs_cols_full="pv_name,vg_name"
       pvs_sort_full="pv_name"
       pvsegs_cols_full="pv_name,pvseg_start,pvseg_size"
       pvsegs_sort_full="pv_uuid,pvseg_start"
       vgs_cols_full="vg_name"
       vgs_sort_full="vg_name"
       lvs_cols_full="lv_name,vg_name"
       lvs_sort_full="vg_name,lv_name"
       segs_cols_full="lv_name,seg_start,seg_size"
       segs_sort_full="lv_uuid,seg_start"

       # lvm fullreport
         VG
         vg
         PV         VG
         /dev/sda   vg
         /dev/sdb   vg
         LV    VG
         lvol0 vg
         lvol1 vg
         PV         Start SSize
         /dev/sda       0     1
         /dev/sda       1     1
         /dev/sda       2     1
         /dev/sda       3    22
         /dev/sdb       0     1
         /dev/sdb       1     1
         /dev/sdb       2    23
         LV    Start SSize
         lvol0    0  4.00m
         lvol1    0  4.00m

   Automatic output compaction
       If  you look at the lvs output above, you can see that the report also contains fields for which there is
       no information to display (e.g. the columns  under  "Origin"  and  "Pool"  heading  -  the  "origin"  and
       "pool_lv"  fields).  LVM can automatically compact report output so such fields are not included in final
       output. To  enable  this  feature  and  to  compact  all  fields,  use  report/compact_output=1  in  your
       configuration.

       # lvmconfig --type full report/compact_output
       compact_output=1

       # lvs
         LV    LSize Cpy%Sync
         lvol1 4.00m 100.00
         lvol0 4.00m

       # lvs vg/lvol0
         LV    LSize
         lvol0 4.00m

       Alternatively,  you can define which fields should be compacted by configuring report/compact_output_cols
       configuration setting (or -o--options # command line option).

       # lvmconfig --type full report/compact_output report/compact_output_cols
       compact_output=0
       compact_output_cols="origin"

       # lvs
         LV    LSize Pool Cpy%Sync
         lvol1 4.00m      100.00
         lvol0 4.00m

       # lvs vg/lvol0
         LV    LSize Pool
         lvol0 4.00m

       # lvs -o#pool_lv
         LV    LSize Origin Cpy%Sync
         lvol1 4.00m        100.00
         lvol0 4.00m

       We will use report/compact_output=1 for subsequent examples.

   Further formatting options
       By default, LVM displays sizes in reports in human-readable form which means that the most suitable  unit
       is  used so it's easy to read. You can use report/units configuration setting (or --units option directly
       on command line) and report/suffix configuration setting (or --nosuffix command line  option)  to  change
       this.

       # lvs --units b --nosuffix
         LV    LSize   Cpy%Sync
         lvol1 4194304 100.00
         lvol0 4194304

       If  you want to configure whether report headings are displayed or not, use report/headings configuration
       settings (or --noheadings command line option).

       # lvs --noheadings
         lvol1 4.00m 100.00
         lvol0 4.00m

       In some cases, it may be useful to display report content as key=value pairs where key here  is  actually
       the  field  name.  Use  report/prefixes  configuration setting (or --nameprefixes command line option) to
       switch between standard output and the key=value output.  The  key=value  pair  is  the  output  that  is
       suitable for use in scripts and for other tools to parse easily.  Usually, you also don't want to display
       headings with the output that has these key=value pairs.

       # lvs --noheadings --nameprefixes
         LVM2_LV_NAME='lvol1' LVM2_LV_SIZE='4.00m' LVM2_COPY_PERCENT='100.00'
         LVM2_LV_NAME='lvol0' LVM2_LV_SIZE='4.00m' LVM2_COPY_PERCENT=''

       To define whether  quotation  marks  in  key=value  pairs  should  be  used  or  not,  use  report/quoted
       configuration setting (or --unquoted command line option).

       # lvs --noheadings --nameprefixes --unquoted
         LVM2_LV_NAME=lvol1 LVM2_LV_SIZE=4.00m LVM2_COPY_PERCENT=100.00
         LVM2_LV_NAME=lvol0 LVM2_LV_SIZE=4.00m LVM2_COPY_PERCENT=

       For  easier  parsing,  you  can even transpose the report so each column now becomes a row in the output.
       This is done with report/output_as_rows configuration setting (or --rows command line option).

       # lvs --noheadings --nameprefixes --unquoted --rows
         LVM2_LV_NAME=lvol1 LVM2_LV_NAME=lvol0
         LVM2_LV_SIZE=4.00m LVM2_LV_SIZE=4.00m
         LVM2_COPY_PERCENT=100.00 LVM2_COPY_PERCENT=

       Use report/separator configuration setting (or --separator command line option) to define your own  field
       separator to use.

       # lvs --noheadings --nameprefixes --unquoted --separator " | "
         LVM2_LV_NAME=lvol1 | LVM2_LV_SIZE=4.00m | LVM2_COPY_PERCENT=100.00
         LVM2_LV_NAME=lvol0 | LVM2_LV_SIZE=4.00m | LVM2_COPY_PERCENT=

       If  you  are  using  your  own  separator,  the  columns  in  the  output are not aligned by default. Use
       report/aligned configuration setting (or --aligned command line option) for LVM to add  extra  spaces  in
       report to align the output properly.

       # lvs --separator " | "
         LV | LSize | Cpy%Sync
         lvol1 | 4.00m | 100.00
         lvol0 | 4.00m |

       # lvs --separator " | " --aligned
         LV    | LSize | Cpy%Sync
         lvol1 | 4.00m | 100.00
         lvol0 | 4.00m |

       Let's display one one more field in addition ("lv_tags" in this example) for the lvs report output.

       # lvs -o+lv_tags
         LV    LSize Cpy%Sync LV Tags
         lvol1 4.00m 100.00
         lvol0 4.00m          tagA,tagB

       The  "LV  Tags"  column  in the example above displays two list values, separated by "," character for LV
       lvol0. If you need different list item separator, use  report/list_item_separator  configuration  setting
       its definition.

       # lvmconfig --type full report/list_item_separator
       list_item_separator=";"

       # lvs -o+tags
         LV    LSize Cpy%Sync LV Tags
         lvol1 4.00m 100.00
         lvol0 4.00m          tagA;tagB

       But let's still use the original "," character for list_item_separator for subsequent examples.

       Format  for  any  of  time  values  displayed  in  reports  can  be  configured  with  report/time_format
       configuretion setting. By default complete date and time is displayed, including timezone.

       # lvmconfig --type full report/time_format
       time_format="%Y-%m-%d %T %z"

       # lvs -o+time
         LV    LSize Cpy%Sync CTime
         lvol1 4.00m 100.00   2016-08-29 12:53:36 +0200
         lvol0 4.00m          2016-08-29 10:15:17 +0200

       We can change time format in similar way as we do when using  date(1)  command  or  strftime(3)  function
       (lvmconfig  --type  default  --withcomments  report/time_format  will give you complete list of available
       formatting options). In the example below, we decided to  use  %s  for  number  of  seconds  since  Epoch
       (1970-01-01 UTC).

       # lvmconfig --type full report/time_format
       time_format="%s"

       # lvs
         LV    Attr       LSize Cpy%Sync LV Tags   CTime
         lvol1 rwi-a-r--- 4.00m 100.00             1472468016
         lvol0 -wi-a----- 4.00m          tagA,tagB 1472458517

       The  lvs  does  not  display  hidden LVs by default - to include these LVs in the output, you need to use
       -a--all command line option. Names for these hidden LVs are displayed within square brackets.

       # lvs -a
         LV               LSize Cpy%Sync
         lvol1            4.00m 100.00
         [lvol1_rimage_0] 4.00m
         [lvol1_rmeta_0]  4.00m
         [lvol1_rimage_1] 4.00m
         [lvol1_rmeta_1]  4.00m
         lvol0            4.00m

       You  can  configure   LVM   to   display   the   square   brackets   for   hidden   LVs   or   not   with
       report/mark_hidden_devices configuration setting.

       # lvmconfig --type full report/mark_hidden_devices
       mark_hidden_devices=0

       # lvs -a
         LV             LSize Cpy%Sync
         lvol1          4.00m 100.00
         lvol1_rimage_0 4.00m
         lvol1_rmeta_0  4.00m
         lvol1_rimage_1 4.00m
         lvol1_rmeta_1  4.00m
         lvol0          4.00m

       It's not recommended to use LV marks for hidden devices to decide whether the LV is the one to use by end
       users or not. Please, use "lv_role" field instead  which  can  report  whether  the  LV  is  "public"  or
       "private". The private LVs are used by LVM only and they should not be accessed directly by end users.

       # lvs -a -o+lv_role
         LV             LSize Cpy%Sync Role
         lvol1          4.00m 100.00   public
         lvol1_rimage_0 4.00m          private,raid,image
         lvol1_rmeta_0  4.00m          private,raid,metadata
         lvol1_rimage_1 4.00m          private,raid,image
         lvol1_rmeta_1  4.00m          private,raid,metadata
         lvol0          4.00m          public

       Some  of  the  reporting  fields  that  LVM  reports  are  of binary nature. For such fields, it's either
       possible to display word representation of the value (this is used by default) or numeric value  (0/1  or
       -1 in case the value is undefined).

       # lvs -o+lv_active_locally
         LV    LSize Cpy%Sync ActLocal
         lvol1 4.00m 100.00   active locally
         lvol0 4.00m          active locally

       We  can  change  the  way  how  these  binary  values  are displayed with report/binary_values_as_numeric
       configuration setting.

       # lvmconfig --type full report/binary_values_as_numeric
       binary_values_as_numeric=1

       # lvs -o+lv_active_locally
         LV    LSize Cpy%Sync ActLocal
         lvol1 4.00m 100.00            1
         lvol0 4.00m                   1

   Changing output format
       LVM can output reports  in  different  formats  -  use  report/output_format  configuration  setting  (or
       --reportformat  command  line  option) to swith the report output format. Currently, LVM supports "basic"
       (all the examples we used above used this format) and "JSON" output format.

       # lvs -o lv_name,lv_size --reportformat json
         {
             "report": [
                 {
                     "lv": [
                         {"lv_name":"lvol1", "lv_size":"4.00m"},
                         {"lv_name":"lvol0", "lv_size":"4.00m"}
                     ]
                 }
             ]
         }

       Note that some configuration settings and command  line  options  have  no  effect  with  certain  report
       formats.  For  example,  with JSON output, it doesn't have any meaning to use report/aligned (--aligned),
       report/noheadings (--noheadings), report/columns_as_rows (--rows) or report/buffered (--unbuffered).  All
       these configuration settings and command line options are ignored if using the JSON report output format.

   Selection
       If  you need to select only specific rows from report, you can use LVM's report selection feature. If you
       call <lvm_command> -S help, you'll get quick help on selection. The help contains list of all fields that
       LVM  can use in reports together with its type enclosed in square brackets.  The example below contains a
       line from lvs -S help.

       # lvs -S help
           ...
           lv_size                - Size of LV in current units. [size]
           ...

       This line tells you you that the "lv_size" field is of "size" type. If you look at the bottom of the help
       output, you can see section about "Selection operators" and its "Comparison operators".

       # lvs -S help
        ...
       Selection operators
       -------------------
       Comparison operators:
          =~  - Matching regular expression. [regex]
          !~  - Not matching regular expression. [regex]
           =  - Equal to. [number, size, percent, string, string list, time]
          !=  - Not equal to. [number, size, percent, string, string_list, time]
          >=  - Greater than or equal to. [number, size, percent, time]
           >  - Greater than. [number, size, percent, time]
          <=  - Less than or equal to. [number, size, percent, time]
           <  - Less than. [number, size, percent, time]
       since  - Since specified time (same as '>='). [time]
       after  - After specified time (same as '>'). [time]
       until  - Until specified time (same as '<='). [time]
       before  - Before specified time (same as '<'). [time]
        ...

       Here you can match comparison operators that you may use with the "lv_size" field which is of type "size"
       - it's =, !=, >=, >, <= and <. You can find applicable comparison operators for other  fields  and  other
       field types the same way.

       To  demostrate  selection functionality in LVM, we will create more LVs in addition to lvol0 and lvol1 we
       used in our previous examples.

       # lvs -o name,size,origin,snap_percent,tags,time
         LV    LSize Origin Snap%  LV Tags        CTime
         lvol4 4.00m lvol2  24.61                 2016-09-09 16:57:44 +0200
         lvol3 4.00m lvol2  5.08                  2016-09-09 16:56:48 +0200
         lvol2 8.00m               tagA,tagC,tagD 2016-09-09 16:55:12 +0200
         lvol1 4.00m                              2016-08-29 12:53:36 +0200
         lvol0 4.00m               tagA,tagB      2016-08-29 10:15:17 +0200

       When selecting size and percent fields, we don't need to use units.  For sizes, default "m" (for MiB)  is
       used  -  this is the same behaviour as already used for LVM commands when specifying sizes (e.g. lvcreate
       -L).  For percent fields, "%" is assumed automatically if it's not specified.   The  example  below  also
       demonstrates how several criteria can be combined together.

       # lvs -o name,size,snap_percent -S 'size=8m'
         LV    LSize
         lvol2 8.00m

       # lvs -o name,size,snap_percent -S 'size=8'
         LV    LSize
         lvol2 8.00m

       # lvs -o name,size,snap_percent -S 'size < 5000k'
         LV    LSize Snap%
         lvol4 4.00m 24.61
         lvol3 4.00m 5.08
         lvol1 4.00m
         lvol0 4.00m

       # lvs -o name,size,snap_percent -S 'size < 5000k && snap_percent > 20'
         LV    LSize Snap%
         lvol4 4.00m 24.61

       # lvs -o name,size,snap_percent \
           -S '(size < 5000k && snap_percent > 20%) || name=lvol2'
         LV    LSize Snap%
         lvol4 4.00m 24.61
         lvol2 8.00m

       You can also use selection together with processing-oriented commands.

       # lvchange --addtag test -S 'size < 5000k'
         Logical volume vg/lvol1 changed.
         Logical volume vg/lvol0 changed.
         Logical volume vg/lvol3 changed.
         Logical volume vg/lvol4 changed.

       # lvchange --deltag test -S 'tags = test'
         Logical volume vg/lvol1 changed.
         Logical volume vg/lvol0 changed.
         Logical volume vg/lvol3 changed.
         Logical volume vg/lvol4 changed.

       LVM  can  recognize  more complex values used in selection criteria for string list and time field types.
       For string lists, you can match whole list strictly, its subset or  intersection.  Let's  take  "lv_tags"
       field  as  an  example  -  we select only rows which contain "tagA" within tags field. We're using { } to
       denote that we're interested in subset that matches. If the subset has only one item, we can leave out  {
       }.

       # lvs -o name,tags -S 'tags={tagA}'
         LV    LV Tags
         lvol2 tagA,tagC,tagD
         lvol0 tagA,tagB

       # lvs -o name,tags -S 'tags=tagA'
         LV    LV Tags
         lvol2 tagA,tagC,tagD
         lvol0 tagA,tagB

       Depending  on  whether we use "&&" (or ",") or "||" ( or "#") as delimiter for items in the set we define
       in selection criterion for string list, we either match subset ("&&" or ",") or even  intersection  ("||"
       or "#").

       # lvs -o name,tags -S 'tags={tagA,tagC,tagD}'
         LV    LV Tags
         lvol2 tagA,tagC,tagD

       # lvs -o name,tags -S 'tags={tagA || tagC || tagD}'
         LV    LV Tags
         lvol2 tagA,tagC,tagD
         lvol0 tagA,tagB

       To  match  the complete set, use [ ] with "&&" (or ",") as delimiter for items.  Also note that the order
       in which we define items in the set is not relevant.

       # lvs -o name,tags -S 'tags=[tagA]'

       # lvs -o name,tags -S 'tags=[tagB,tagA]'
         LV    LV Tags
         lvol0 tagA,tagB

       If you use [ ] with "||" (or "#"), this is exactly the same as using { }.

       # lvs -o name,tags -S 'tags=[tagA || tagC || tagD]'
         LV    LV Tags
         lvol2 tagA,tagC,tagD
         lvol0 tagA,tagB

       To match a set with no items, use "" to denote this (note that we have output compaction enabled  so  the
       "LV Tags" column is not displayed in the example below because it's blank and so it gets compacted).

       # lvs -o name,tags -S 'tags=""'
         LV
         lvol4
         lvol3
         lvol1

       # lvs -o name,tags -S 'tags!=""'
         LV    LV Tags
         lvol2 tagA,tagC,tagD
         lvol0 tagA,tagB

       When  doing  selection  based  on  time  fields,  we  can  use either standard, absolute or freeform time
       expressions in selection criteria. Examples below are using standard forms.

       # lvs -o name,time
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time -S 'time since "2016-09-01"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200

       # lvs -o name,time -S 'time since "2016-09-09 16:56"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200

       # lvs -o name,time -S 'time since "2016-09-09 16:57:30"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200

       # lvs -o name,time \
           -S 'time since "2016-08-29" && time until "2016-09-09 16:55:12"'
         LV    CTime
         lvol2 2016-09-09 16:55:12 +0200
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time \
           -S 'time since "2016-08-29" && time before "2016-09-09 16:55:12"'
         LV    CTime
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       Time operators have synonyms: ">=" for since, "<=" for until, ">" for "after" and "<" for "before".

       # lvs -o name,time \
           -S 'time >= "2016-08-29" && time <= "2016-09-09 16:55:30"'
         LV    CTime
         lvol2 2016-09-09 16:55:12 +0200
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time \
           -S 'time since "2016-08-29" && time < "2016-09-09 16:55:12"'
         LV    CTime
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       Example below demonstrates using absolute time expression.

       # lvs -o name,time --config report/time_format="%s"
         LV    CTime
         lvol4 1473433064
         lvol3 1473433008
         lvol2 1473432912
         lvol1 1472468016
         lvol0 1472458517

       # lvs -o name,time -S 'time since @1473433008'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200

       Examples below demonstrates using freeform time expressions.

       # lvs -o name,time -S 'time since "2 weeks ago"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time -S 'time since "1 week ago"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200

       # lvs -o name,time -S 'time since "2 weeks ago"'
         LV    CTime
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time -S 'time before "1 week ago"'
         LV    CTime
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

       # lvs -o name,time -S 'time since "68 hours ago"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200

       # lvs -o name,time -S 'time since "1 year 3 months ago"'
         LV    CTime
         lvol4 2016-09-09 16:57:44 +0200
         lvol3 2016-09-09 16:56:48 +0200
         lvol2 2016-09-09 16:55:12 +0200
         lvol1 2016-08-29 12:53:36 +0200
         lvol0 2016-08-29 10:15:17 +0200

   Command log reporting
       As described in categorization based on reporting facility section at the  beginning  of  this  document,
       both  report-oriented  and processing-oriented LVM commands can report the command log if this is enabled
       with log/report_command_log configuration setting.  Just like any other report, we can  set  the  set  of
       fields to display (log/command_log_cols) and to sort by (log/command_log_sort) for this report.

       # lvmconfig --type full log/report_command_log log/command_log_cols \
          log/command_log_sort log/command_log_selection
       report_command_log=1
       command_log_cols="log_seq_num,log_type,log_context,log_object_type,
                         log_object_name,log_object_group,log_message,
                         log_errno,log_ret_code"
       command_log_sort="log_seq_num"
       command_log_selection="!(log_type=status && message=success)"

       # lvs
         Logical Volume
         ==============
         LV    LSize Cpy%Sync
         lvol1 4.00m 100.00
         lvol0 4.00m

         Command Log
         ===========
         Seq LogType Context ObjType ObjName ObjGrp  Msg     Errno RetCode

       As  you can see, the command log is empty (it contains only field names).  By default, LVM uses selection
       on the command log report and this case no row matched  the  selection  criteria,  see  also  log  report
       specifics  section  in  this  document  for more information. We're displaying complete log report in the
       example below where we can see that both LVs lvol0 and lvol1 were successfully processed as well  as  the
       VG vg they are part of.

       # lvmconfig --type full log/command_log_selection
       command_log_selection="all"

       # lvs
         Logical Volume
         ==============
         LV    LSize Cpy%Sync
         lvol1 4.00m 100.00
         lvol0 4.00m

         Command Log
         ===========
         Seq LogType Context    ObjType ObjName ObjGrp  Msg     Errno RetCode
           1 status  processing lv      lvol0   vg      success     0       1
           2 status  processing lv      lvol1   vg      success     0       1
           3 status  processing vg      vg              success     0       1

       # lvchange -an vg/lvol1
         Command Log
         ===========
         Seq LogType Context    ObjType ObjName ObjGrp  Msg     Errno RetCode
           1 status  processing lv      lvol1   vg      success     0       1
           2 status  processing vg      vg              success     0       1

   Handling multiple reports per single command
       To  configure  the  log  report  directly on command line, we need to use --configreport option before we
       start any -o--options, -O--sort or -S--select that is targeted for log report.

       # lvs -o lv_name,lv_size --configreport log -o log_object_type, \
          log_object_name,log_message,log_ret_code
         Logical Volume
         ==============
         LV    LSize
         lvol1 4.00m
         lvol0 4.00m

         Command Log
         ===========
         ObjType ObjName Msg     RetCode
         lv      lvol0   success       1
         lv      lvol1   success       1
         vg      vg      success       1

       The lvm fullreport, with or without log report, consists of several reports - the --configreport is  also
       used to target particular subreport here.

       Below is an extended example with lvm fullreport to illustrate combination of various options. The report
       output is in JSON format.  Also, we configure "vg", "pvseg", "seg" and "log" subreport  to  contain  only
       specified  fields. For the "pvseg" subreport, we're intested only in PV names having "sda" in their name.
       For the "log" subreport we're intested only in log lines related  to  either  "lvol0"  object  or  object
       having "sda" in its name. Also, for the log subreport we define ordering to be based on "log_object_type"
       field.

       # lvm fullreport --reportformat json \
          --configreport vg -o vg_name,vg_size \
          --configreport pvseg -o pv_name,pvseg_start \
                               -S 'pv_name=~sda' \
          --configreport seg -o lv_name,seg_start \
          --configreport log -o log_object_type,log_object_name \
                             -O log_object_type \
                             -S 'log_object_name=lvol0 || \
                                 log_object_name=~sda'
         {
             "report": [
                 {
                     "vg": [
                         {"vg_name":"vg", "vg_size":"200.00m"}
                     ]
                     ,
                     "pv": [
                         {"pv_name":"/dev/sda", "vg_name":"vg"},
                         {"pv_name":"/dev/sdb", "vg_name":"vg"}
                     ]
                     ,
                     "lv": [
                         {"lv_name":"lvol0", "vg_name":"vg"},
                         {"lv_name":"lvol1", "vg_name":"vg"}
                     ]
                     ,
                     "pvseg": [
                         {"pv_name":"/dev/sda", "pvseg_start":"0"},
                         {"pv_name":"/dev/sda", "pvseg_start":"1"},
                         {"pv_name":"/dev/sda", "pvseg_start":"2"},
                         {"pv_name":"/dev/sda", "pvseg_start":"3"}
                     ]
                     ,
                     "seg": [
                         {"lv_name":"lvol0", "seg_start":"0 "},
                         {"lv_name":"lvol1", "seg_start":"0 "}
                     ]
                 }
             ]
             ,
             "log": [
                 {"log_object_type":"lv", "log_object_name":"lvol0"},
                 {"log_object_type":"lv", "log_object_name":"lvol0"},
                 {"log_object_type":"pv", "log_object_name":"/dev/sda"},
                 {"log_object_type":"pv", "log_object_name":"/dev/sda"},
             ]
         }

   Report extensions for LVM shell
       As already stated in log report coverage paragraph under log report specifics in this documentation, when
       using  LVM  shell  the  log report coverage is wider. There's also special command designed to query last
       command's log report in the LVM shell - the lastlog command.

       The example below illustrates a situation where we called lvs command.  After that, we inspected the  log
       report  with  the  lastlog,  without  any selection so all the log report is displayed on output. Then we
       called lastlog further, giving various selection criteria. Then we ran  unknown  LVM  command  "abc"  for
       which the log report displays appropriate failure state.

       # lvm
       lvm> lvs
         Logical Volume
         ==============
         LV    LSize Cpy%Sync
         lvol1 4.00m 100.00
         lvol0 4.00m

         Command Log
         ===========
         Seq LogType Context    ObjType ObjName ObjGrp  Msg     Errno RetCode
           1 status  processing lv      lvol0   vg      success     0       1
           2 status  processing lv      lvol1   vg      success     0       1
           3 status  processing vg      vg              success     0       1
           4 status  shell      cmd     lvs             success     0       1

       lvm> lastlog
         Command Log
         ===========
         Seq LogType Context    ObjType ObjName ObjGrp  Msg     Errno RetCode
           1 status  processing lv      lvol0   vg      success     0       1
           2 status  processing lv      lvol1   vg      success     0       1
           3 status  processing vg      vg              success     0       1
           4 status  shell      cmd     lvs             success     0       1

       lvm> lastlog -S log_object_type=lv
         Command Log
         ===========
         Seq LogType Context    ObjType ObjName ObjGrp  Msg     Errno RetCode
           1 status  processing lv      lvol0   vg      success     0       1
           2 status  processing lv      lvol1   vg      success     0       1

       lvm> lastlog -S log_context=shell
         Command Log
         ===========
         Seq LogType Context ObjType ObjName ObjGrp  Msg     Errno RetCode
           4 status  shell   cmd     lvs             success     0       1

       lvm> abc
         Command Log
         ===========
         Seq LogType Context ObjType ObjName ObjGrp  Msg                                 Errno RetCode
           1 error   shell   cmd     abc             No such command 'abc'.  Try 'help'.    -1       0
           2 status  shell   cmd     abc             failure                                -1       2

SEE ALSO

       lvm (8), lvmconfig (8), lvm fullreport (8)