Hello list, I found below question solution, executing removemissing with "--mirrorsonly" is mandatory. ``` vgreduce --removemissing --mirrorsonly --force VG lvconvert -m0 VG/data_lv ``` But there raise another issue. the default error message is not clear. When vgreduce on mirrored & cached LVs, user normally runs below command & get below failed messages: ``` # vgreduce --removemissing VG WARNING: Couldn't find device with uuid UQZkRE-P8X7-Pkgv-mE5b-q6CY-2DmX-ew2BCn. WARNING: VG VG is missing PV UQZkRE-P8X7-Pkgv-mE5b-q6CY-2DmX-ew2BCn. WARNING: Couldn't find all devices for LV VG/data_lv_corig_rimage_1 while checking used and assumed devices. WARNING: Couldn't find all devices for LV VG/data_lv_corig_rmeta_1 while checking used and assumed devices. WARNING: Couldn't find device with uuid UQZkRE-P8X7-Pkgv-mE5b-q6CY-2DmX-ew2BCn. WARNING: Partial LV data_lv needs to be repaired or removed. WARNING: Partial LV data_lv_corig_rimage_1 needs to be repaired or removed. WARNING: Partial LV data_lv_corig_rmeta_1 needs to be repaired or removed. WARNING: Partial LV data_lv_corig needs to be repaired or removed. There are still partial LVs in VG VG. To remove them unconditionally use: vgreduce --removemissing --force. <===== this command is very dangerous for this mail's scenario WARNING: Proceeding to remove empty missing PVs. WARNING: Couldn't find device with uuid UQZkRE-P8X7-Pkgv-mE5b-q6CY-2DmX-ew2BCn. ``` Currently the error info are not clear. This very easy to guide user to execute "--removemissing --force", then the LVs will be destroied. So I filed a patch for this little issue on next mail. thanks you. On 11/29/19 4:35 PM, Heming Zhao wrote: > Hello list, > > I met a lvm cache issue recently. > > The machine had an LVM VG configured with: > dev1 + dev2 -> data_lv with raid 1 mirror > dev3 + dev4 -> data_cache_lv with raid 1 mirror and type cache > > These were assembled to a cached volume with: > "lvconvert --type cache --cachemode writeback --cachepool data/data_cache_lv data/data_lv" > > The device dev4 then died and was removed from the system. > > When attempting to remove the device using "vgreduce --removemissing", lvm removed both data_cache_lv and data_lv from the data vg. > > This is unexpected behaviour, as dev1, dev2, dev3 were all still present. > The expected behaviour should: > ``` > vgreduce --removemissing > lvconvert -m0 system/lv > ``` > > When it's a non-cached type, and you performe vgreduce, lvs are NOT removed. > > the (reproduced) command list: > ``` > pvcreate /dev/mapper/dev1 /dev/mapper/dev2 /dev/mapper/dev3 /dev/mapper/dev4 > vgcreate VG /dev/mapper/dev1 /dev/mapper/dev2 /dev/mapper/dev3 /dev/mapper/dev4 > lvcreate --type raid1 -m 1 -L150 -n data_lv VG /dev/mapper/dev1 /dev/mapper/dev2 > lvcreate --type raid1 -m 1 -L150 -n data_cache_lv VG /dev/mapper/dev3 /dev/mapper/dev4 > lvconvert --type cache --cachemode writeback --cachepool VG/data_cache_lv VG/data_lv > dmsetup remove -f dev4 > vgreduce --removemissing --force VG > ``` > > Thanks. > > _______________________________________________ > linux-lvm mailing list > linux-lvm@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > > _______________________________________________ linux-lvm mailing list linux-lvm@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
