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C.4. Selection Criteria Display Examples

This section provides a series of examples showing how to use selection criteria for LVM display commands. The examples in this section use a system configured with LVM volumes that yield the following output when selection criteria are not used.
# lvs -a -o+layout,role
  LV              VG Attr       LSize   Pool Origin Data%  Meta%  Layout      Role
  root            f1 -wi-ao----   9.01g                           linear      public
  swap            f1 -wi-ao---- 512.00m                           linear      public
  [lvol0_pmspare] vg ewi-------   4.00m                           linear      private,   \
                                                                              pool,spare
  lvol1           vg Vwi-a-tz--   1.00g pool        0.00          thin,sparse public
  lvol2           vg Vwi-a-tz--   1.00g pool        0.00          thin,sparse public,    \
                                                                              origin,    \
                                                                              thinorigin
  lvol3           vg Vwi---tz-k   1.00g pool lvol2                thin,sparse public,    \
                                                                              snapshot,  \
                                                                              thinsnapshot
  pool            vg twi-aotz-- 100.00m             0.00   1.07   thin,pool   private
  [pool_tdata]    vg Twi-ao---- 100.00m                           linear      private,   \
                                                                              thin,pool, \
                                                                              data
  [pool_tmeta]    vg ewi-ao----   4.00m                           linear      private,   \
                                                                              thin,pool, \
                                                                              metadata
The following command displays all logical volumes with "lvol[13]" in their name, using a regular expression to specify this.
# lvs -a -o+layout,role -S 'lv_name=~lvol[13]'
  LV    VG   Attr       LSize Pool Origin Data%  Layout      Role                        
  lvol1 vg   Vwi-a-tz-- 1.00g pool        0.00   thin,sparse public                      
  lvol3 vg   Vwi---tz-k 1.00g pool lvol2         thin,sparse public,snapshot,thinsnapshot
The following command displays all logical volumes greater than 500m in size.
# lvs -a -o+layout,role -S 'lv_size>500m'
  LV    VG Attr       LSize   Pool Origin Data%  Layout      Role                        
  root  f1 -wi-ao----   9.01g                    linear      public                      
  swap  f1 -wi-ao---- 512.00m                    linear      public                      
  lvol1 vg Vwi-a-tz--   1.00g pool        0.00   thin,sparse public                      
  lvol2 vg Vwi-a-tz--   1.00g pool        0.00   thin,sparse public,origin,thinorigin    
  lvol3 vg Vwi---tz-k   1.00g pool lvol2         thin,sparse public,snapshot,           \
                                                             thinsnapshot
The following command displays all logical volumes that include thin as a logical volume role, indicating that the logical volume is used in constructing a thin pool. This example uses braces ({}) to indicate a subset in the display.
# lvs -a -o+layout,role -S 'lv_role={thin}'
  LV           VG   Attr       LSize   Layout     Role                      
  [pool_tdata] vg   Twi-ao---- 100.00m linear     private,thin,pool,data    
  [pool_tmeta] vg   ewi-ao----   4.00m linear     private,thin,pool,metadata
The following command displays all usable top-level logical volumes, which are the logical volumes with a role of "public". If you do not specify braces ({}) in a string list to indicate a subset, it is assumed by default; specifying lv_role=public is equivalent to specifying lv_role={public}.
# lvs -a -o+layout,role -S 'lv_role=public' 
  LV    VG Attr       LSize   Pool Origin Data%  Layout      Role                        
  root  f1 -wi-ao----   9.01g                    linear      public                      
  swap  f1 -wi-ao---- 512.00m                    linear      public                      
  lvol1 vg Vwi-a-tz--   1.00g pool        0.00   thin,sparse public                      
  lvol2 vg Vwi-a-tz--   1.00g pool        0.00   thin,sparse public,origin,thinorigin 
  lvol3 vg Vwi---tz-k   1.00g pool lvol2         thin,sparse public,snapshot,thinsnapshot
The following command displays all logical volumes with a thin layout.
# lvs -a -o+layout,role -S 'lv_layout={thin}'
  LV    VG Attr       LSize   Pool Origin Data% Meta% Layout      Role 
  lvol1 vg Vwi-a-tz--   1.00g pool        0.00        thin,sparse public 
  lvol2 vg Vwi-a-tz--   1.00g pool        0.00        thin,sparse public,origin,          \
                                                                  thinorigin    
  lvol3 vg Vwi---tz-k   1.00g pool lvol2              thin,sparse public,snapshot,        \
                                                                  thinsnapshot
  pool  vg twi-aotz-- 100.00m             0.00  1.07  thin,pool   private
The following command displays all logical volumes with a layout field that matches "sparse,thin" exactly. Note that it is not necessary to specify the string list members for the match to be positive.
# lvs -a -o+layout,role -S 'lv_layout=[sparse,thin]'
  LV    VG   Attr       LSize Pool Origin Data%  Layout      Role                        
  lvol1 vg   Vwi-a-tz-- 1.00g pool        0.00   thin,sparse public                      
  lvol2 vg   Vwi-a-tz-- 1.00g pool        0.00   thin,sparse public,origin,thinorigin    
  lvol3 vg   Vwi---tz-k 1.00g pool lvol2         thin,sparse public,snapshot,thinsnapshot
The following command displays the logical volume names of the logical volumes that are thin, sparse logical volumes. Note that the list of fields used for selection criteria do not need to be the same as the list of fields to display.
# lvs -a -o lv_name -S 'lv_layout=[sparse,thin]'
  LV   
  lvol1
  lvol2
  lvol3