NAME
lvmreport — LVM reporting and related featuresDESCRIPTION
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.USAGE
Categorization based on reporting facility
Based on functionality, commands which make use of the reporting infrastructure are divided in two groups:- Report-oriented commands
- 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 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.
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/suffix
- Special settings
- - report/buffered
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 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.
- -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 fields sets configured with global configuration settings that this options 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.
- --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/buffered configuration setting.
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
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
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
- 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
- Return code associated with current item.
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 -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
- 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
- •
- 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"}
- •
- 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
"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
- -
- @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")
- -
- STATEMENT = column cmp_op VALUE | STATEMENT log_op STATEMENT | (STATEMENT) | !(STATEMENT)
- -
-
VALUE = [VALUE log_op VALUE]
- -
-
VALUE = {VALUE log_op VALUE}
- -
-
VALUE = 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=1Also, 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 4.00mWe 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 4.00mYou 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,raid1You 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 4.00mAlternatively, 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 4.00mWe 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 4194304If 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 4.00mIn 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,tagBThe "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;tagBBut 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 +0200We 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 1472458517The 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 4.00mYou 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 4.00mIt'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 publicSome 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 locallyWe 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 -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 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 +0200When 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 8.00mYou 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,tagBDepending 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,tagBTo 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,tagBIf 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,tagBTo 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,tagBWhen 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 +0200Time 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 +0200Example 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 +0200Examples 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 RetCodeAs 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 1The 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 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), lvcreate(8),LVM TOOLS 2.03.16(2) (2022-05-18) | Red Hat, Inc |