Description of problem: This is a pretty low priority issue, but I came across it when running through the matrix of volumes that can be cached. [root@host-110 ~]# vgcreate vg /dev/sd[abcdefgh]1 Volume group "vg" successfully created [root@host-110 ~]# lvcreate -n pool -L 500M vg /dev/sdf1 Logical volume "pool" created. [root@host-110 ~]# lvcreate -n meta -L 50M vg /dev/sdg1 Rounding up size to full physical extent 52.00 MiB Logical volume "meta" created. [root@host-110 ~]# lvconvert --yes --type cache-pool --poolmetadata vg/meta vg/pool WARNING: Converting logical volume vg/pool and vg/meta to pool's data and metadata volumes. THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.) Converted vg/pool to cache pool. [root@host-110 ~]# lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Meta% Cpy%Sync Devices [lvol0_pmspare] vg ewi------- 52.00m /dev/sda1(0) pool vg Cwi---C--- 500.00m pool_cdata(0) [pool_cdata] vg Cwi------- 500.00m /dev/sdf1(0) [pool_cmeta] vg ewi------- 52.00m /dev/sdg1(0) [root@host-110 ~]# lvcreate --thinpool corigin -L 500M --poolmetadatasize 50M vg /dev/sdh1 Rounding up size to full physical extent 52.00 MiB Logical volume "corigin" created. [root@host-110 ~]# lvconvert --yes --type cache --cachepool vg/pool vg/corigin Logical volume vg/corigin_tdata is now cached. [root@host-110 ~]# lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Meta% Cpy%Sync Devices corigin vg twi-a-tz-- 500.00m 0.00 0.07 corigin_tdata(0) [corigin_tdata] vg Cwi-aoC--- 500.00m [pool] [corigin_tdata_corig] 0.00 0.17 100.00 corigin_tdata_corig(0) [corigin_tdata_corig] vg owi-aoC--- 500.00m /dev/sdh1(0) [corigin_tmeta] vg ewi-ao---- 52.00m /dev/sdh1(125) [lvol0_pmspare] vg ewi------- 52.00m /dev/sda1(0) [pool] vg Cwi---C--- 500.00m 0.00 0.17 100.00 pool_cdata(0) [pool_cdata] vg Cwi-ao---- 500.00m /dev/sdf1(0) [pool_cmeta] vg ewi-ao---- 52.00m /dev/sdg1(0) [root@host-110 ~]# lvs -o lv_name --select 'pool_lv=pool' [root@host-110 ~]# Version-Release number of selected component (if applicable): 3.10.0-296.el7.x86_64 lvm2-2.02.125-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 lvm2-libs-2.02.125-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 lvm2-cluster-2.02.125-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 device-mapper-1.02.102-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 device-mapper-libs-1.02.102-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 device-mapper-event-1.02.102-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 device-mapper-event-libs-1.02.102-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 device-mapper-persistent-data-0.5.4-1.el7 BUILT: Fri Jul 17 08:56:22 CDT 2015 cmirror-2.02.125-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015 sanlock-3.2.4-1.el7 BUILT: Fri Jun 19 12:48:49 CDT 2015 sanlock-lib-3.2.4-1.el7 BUILT: Fri Jun 19 12:48:49 CDT 2015 lvm2-lockd-2.02.125-2.el7 BUILT: Fri Jul 10 03:42:29 CDT 2015
That's because the pool lv is in this case marked as internal LV [pool] (with the brackets) - I've got a patch which is a part of another patchset on my devel branch that deals with this (though for string list types, not for string type alone, but I'll do that for string types too) and when doing the comparison, it ignores the [] decoration (or any other possible registered decoration).
(In reply to Corey Marthaler from comment #0) > [root@host-110 ~]# lvs -o lv_name --select 'pool_lv=pool' > [root@host-110 ~]# I've checked this - actually we do report "[blabla]" on output, but still the raw value is "blabla" which makes it selectable just fine (as raw values are used for selection). You just missed the "-a" for your lvs - the selection is done on the list that would be reported normally and without "-a" the [corigin_tdata] is hidden. # lvs -o lv_name -S 'pool_lv=pool' (nothing) #lvs -a -o lv_name -S 'pool_lv=pool' LV [corigin_tdata]