VDO TOPICS
   1. Stacking VDO
       You can convert or stack a VDOPooLV with these currently supported volume types: linear, stripe, raid and cache with cachepool.

   2. VDOPoolLV on top of raid
       Using a raid type LV for a VDODataLV.

       Example
       # lvcreate --type raid1 -L 5G -n vdopool vg
       # lvconvert --type vdo-pool -V 10G vg/vdopool


[root@virt-019 ~]# lvcreate --type raid1 -L 5G -n vdopool vg
  Logical volume "vdopool" created.
[root@virt-019 ~]# lvs -a -o +devices
  LV                 VG            Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert Devices                                
  root               rhel_virt-019 -wi-ao----  <6.20g                                                     /dev/vda2(205)                         
  swap               rhel_virt-019 -wi-ao---- 820.00m                                                     /dev/vda2(0)                           
  vdopool            vg            rwi-a-r---   5.00g                                    31.60            vdopool_rimage_0(0),vdopool_rimage_1(0)
  [vdopool_rimage_0] vg            iwi-aor---   5.00g                                                     /dev/sda(1)                            
  [vdopool_rimage_1] vg            Iwi-aor---   5.00g                                                     /dev/sdb(1)                            
  [vdopool_rmeta_0]  vg            ewi-aor---   4.00m                                                     /dev/sda(0)                            
  [vdopool_rmeta_1]  vg            ewi-aor---   4.00m                                                     /dev/sdb(0)                            
 
[root@virt-019 ~]# lvconvert --type vdo-pool -V 10G vg/vdopool
  WARNING: Converting logical volume vg/vdopool to VDO pool volume with formatting.
  THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
Do you really want to convert vg/vdopool? [y/n]: y
    The VDO volume can address 2 GB in 1 data slab.
    It can grow to address at most 16 TB of physical storage in 8192 slabs.
    If a larger maximum size might be needed, use bigger slabs.
  device-mapper: remove ioctl on  (253:6) failed: Device or resource busy
  Logical volume "lvol0" created.
  Converted vg/vdopool to VDO pool volume and created virtual vg/lvol0 VDO volume.

kernel-5.14.0-427.el9    BUILT: Fri Feb 23 07:31:31 AM CET 2024
lvm2-2.03.23-2.el9    BUILT: Sat Feb  3 01:10:34 AM CET 2024
lvm2-libs-2.03.23-2.el9    BUILT: Sat Feb  3 01:10:34 AM CET 2024