# lvmreport

## NAME



           lvmreport — LVM reporting and related features
    


## DESCRIPTION



           LVM uses a 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.
    


## USAGE



       **Categorization based on reporting facility**
           Based on functionality, commands which make use of the reporting
           infrastructure are divided into two groups:
    
           **Report-oriented commands**
                  These commands inform about current LVM state and their
                  primary role is to display this information in a concise
                  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 commands**
                  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 a 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**.  The 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/suffix
                  – global/units
                  – report/aligned
                  – report/binary_values_as_numeric
                  – report/columns_as_rows
                  – report/compact_output
                  – report/compact_output_cols
                  – report/headings
                  – report/list_item_separator
                  – report/mark_hidden_devices
                  – report/output_format
                  – report/prefixes
                  – report/quoted
                  – report/separator
                  – report/time_format
                  – 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 of fields to use
    
                  **-o** |**--options** _FieldSet_
                         Field set to use. See **main report specifics** and **log**
                         **report specifics** for information about field sets
                         configured with global configuration settings that
                         this option overrides.
    
                  **-o** |**--options +**_FieldSet_
                         Fields to include in 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.
    
                  **-o** |**--options -**_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.
    
                  **-o** |**--options #**_FieldSet_
                         Compaction of unused fields. Overrides
                         report/compact_output_cols configuration setting.
    
           Sorting
    
                  **-O** |**--sort +**_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.
    
                  **-O** |**--sort -**_FieldSet_
                         Fields to sort by in descending order. See **main**
                         **report specifics** and **log report specifics** for
                         information about field sets configured with global
                         configuration settings that this option overrides.
    
           Selection
    
                  **-S** |**--select** _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.
    
                  **--headings**
                         Overrides report/headings configuration settings.
    
                  **--nameprefixes**
                         Overrides report/prefixes configuration setting.
    
                  **--noheadings**
                         Overrides report/headings 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/buffered 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 **se‐**
           **lection criteria** , see also **Selection** paragraph below for more in‐
           formation about constructing these criteria.
    
       **Main report specifics**
           The **main report** currently encompasses these distinct subtypes,
           referenced by their name – _ReportName_ as listed below.  The com‐
           mand 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 def‐
           inition (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 subse‐
           quent **-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.  There‐
           fore, the **--configreport** is particularly suitable for the full re‐
           port  if you need to configure each of its subreports in a differ‐
           ent way.
    
       **Log report specifics**
           You can enable log report with  **log/report_command_log** configura‐
           tion  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** |**--op‐**
           **tions** , **-O** |**--sort** or **-S** |**--selection** to override configuration set‐
           tings directly on command line for **log report**. When compared to
           **main report** , in addition to usual configuration settings for re‐
           port fields and sorting, the **log report** has also configuration op‐
           tion for selection - **report/command_log_selection**. This configura‐
           tion setting is provided for convenience so it's not necessary to
           use **-S** |**--select** on command line each time an LVM command is exe‐
           cuted 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. To see unfiltered command log, use **"all"** value for the se‐
           lection. 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 mo‐
           ment 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 re‐**
           **port**. By default, that is **standard error output** for error and
           warning messages and **standard output** for common print-like mes‐
           sages.
    
           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 com‐
           mands. 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 exe‐
           cuted in the shell and then, after the command's run, the shell
           needs to display the log report for that recently executed com‐
           mand. 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 de‐
           scription 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 pro‐
           viding 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 con‐
                         texts are identified:
    
                         **shell** for the log collected in the outermost code
                                before and after executing concrete LVM com‐
                                mands
    
                         **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 mes‐
                         sage of that type that got issued.
    
           Object information (used only if applicable):
    
                  _log_object_type field_
                         Type of the object processed. Currently, these ob‐
                         ject 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_
                         Return code associated with current item.
    
           You can also run **lvm --configreport log -o help** to display com‐
           plete list of fields that you may use for the **log report**.
    
       **Selection**
           Selection is used for a report to display only rows that match **se‐**
           **lection criteria**. All rows are displayed with the additional **se‐**
           **lected** field (**-o selected**) displaying 1 if the row matches the _Se‐_
           _lection_ and 0 otherwise. The **selection criteria** are a set of
           **statements** combined by **logical and grouping operators**.  The **state‐**
           **ment** 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 -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 (_log_op_)
                         **& &     **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 -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 all items in the string list field:**
    
              –  and all items from selection, use [ ] with "," (or "&&"),
                 .e.g. ["a","b","c"],
    
              –  and any item from selection, use [ ] with "#" (or "||"),
                 .e.g. ["a"#"b"#"c"].
    
           •  **Matching a subset of items in the string list field:**
    
              –  and all items from selection, use { } with "," (or "&&"),
                 e.g. {"a","b","c"},
    
              –  and any item from selection, use { } with "#" (or "||"),
                 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 all items in list.
             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 of items in
             list.  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).  Also for list-based types: string list (in this case
             the value is a short form of {value}).
    


## 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 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** configuration 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
    
           In certain cases, you may find it more useful to report full
           column names instead of abbreviated column names in report
           headings. To do this, use **report/headings=2** configuration setting
           (or **--headings full** or **--headings 2** command line option). The full
           column names are the exact names that you also use in _FieldSet_ for
           **-o|--options**.  These names are unambiguous, without spaces (one
           word only) and they also make it easier to match the output with
           requested _FieldSet_ :
    
           # lvs -o+seg_start,seg_start_pe
             LV    VG LSize Cpy%Sync Start Start
             lvol0 vg 4.00m             0      0
             lvol1 vg 4.00m 100.00      0      0
    
           # lvs --headings full -o+seg_start,seg_start_pe
             lv_name vg_name lv_size copy_percent seg_start seg_start_pe
             lvol0   vg        4.00m                     0             0
             lvol1   vg        4.00m 100.00              0             0
    
       **Changing output format**
           LVM can output reports in different formats – use
           **report/output_format** configuration setting (or **--reportformat**
           command line option) to switch the report output format.
    
           Currently, LVM supports these output formats:
                  – **"basic"**(all the examples we used above used this
                  format),
                  – **"json"** ,
                  – **"json_std"**.
    
           For example:
           # lvs -o lv_name,lv_size --reportformat json
             {
                 "report": [
                     {
                         "lv": [
                             {"lv_name":"lvol1", "lv_size":"4.00m"},
                             {"lv_name":"lvol0", "lv_size":"4.00m"}
                         ]
                     }
                 ]
             }
    
           The **json_std** output format is more compliant with JSON standard
           and compared to the original **json** format:
    
           – it does not use double quotes around numeric values,
    
           – numeric values are always expressed as numbers, not reserved
             strings representing them (this also means that
             report/binary_values_as_numeric=1 setting is forced)
    
           – it uses 'null' for undefined numeric values,
    
           – it prints string list as proper JSON array of strings instead of
             a single string.
    
           Note that some configuration settings and command line options
           have no effect with certain report formats. For example, with **json**
           or **json_std** 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** or **json_std** 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 -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 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 demonstrate 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
    
           For string list values, we can either match all items in the
           string list value (by using [ ]) or only a subset of items in the
           string list value (by using { }). Further, we can either match if
           all items in the string list selection criterion match (by using
           "," or "&&" as item delimiter) or if only a subset of items in the
           string list selection criterion match (by using "#" or "||" as
           item delimiter).
    
           # lvs -o name,tags -S 'tags={tagA}'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags={tagA || tagB}'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags={tagA && tagB}'
             LV    LV Tags
             lvol0 tagA,tagB
    
           # lvs -o name,tags -S 'tags={tagA || tagB || tagC}'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags={tagA && tagB && tagC}'
    
           # lvs -o name,tags -S 'tags=[tagA]'
    
           # lvs -o name,tags -S 'tags=[tagA || tagB]'
             LV    LV Tags
             lvol0 tagA,tagB
    
           # lvs -o name,tags -S 'tags=[tagA && tagB]'
             LV    LV Tags
             lvol0 tagA,tagB
    
           # lvs -o name,tags -S 'tags=[tagA || tagB || tagC]'
             LV    LV Tags
             lvol0 tagA,tagB
    
           # lvs -o name,tags -S 'tags=[tagA && tagB && tagC]'
    
           You can also use regular expressions instead of simple strings
           inside the string list selection criteria. In that case, the "=~"
           operator is used instead of "=". The string list grouping
           operators { } and [ ] are also recognized.
           # lvs -o name,tags -S 'tags=~^t.*[ACD]$'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags=~{"^t.*[ACD]$"}'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags=~["^t.*[ACD]$"]'
             LV    LV Tags
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags=~{"^t.*[AC]$" || "^tag[D]$" }'
             LV    LV Tags
             lvol0 tagA,tagB
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags=~["^t.*[AC]$" || "^tag[D]$" ]'
             LV    LV Tags
             lvol2 tagA,tagC,tagD
    
           # lvs -o name,tags -S 'tags=~["^t.*A$" && "^t.*B$" ]'
             LV    LV Tags
             lvol0 tagA,tagB
    
           # lvs -o name,tags -S 'tags!~["^t.*A$" && "^t.*B$" ]'
             LV    LV Tags
             lvol1
             lvol2 tagA,tagC,tagD
             lvol3
             lvol4
    
           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 interested only in PV names having "sda" in their
           name. For the "log" subreport we're interested 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  →
               1 error   shell   cmd     abc            No such command 'abc'. Try 'help'.
               2 status  shell   cmd     abc            failure
               → Errno RetCode
                    -1       0
                    -1       2
    


* * *