knossos:/home/heidi# mdadm -C /dev/md0 -n2 -l 1 /dev/hdc missing
mdadm: array /dev/md0 started.
knossos:/home/heidi# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 hdc[0]
      195360896 blocks [2/1] [U_]

unused devices: <none>
knossos:/home/heidi# pvcreate /dev/md0
  Physical volume "/dev/md0" successfully created
knossos:/home/heidi# vgdisplay
  --- Volume group ---
  VG Name               knossos
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  80
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               186.31 GB
  PE Size               4.00 MB
  Total PE              47695
  Alloc PE / Size       33280 / 130.00 GB
  Free  PE / Size       14415 / 56.31 GB
  VG UUID               xccB3F-8F8A-YzcP-jMNJ-rIkV-jxZ3-cueJwp

knossos:/home/heidi# pvdisplay
  --- Physical volume ---
  PV Name               /dev/hdb
  VG Name               knossos
  PV Size               186.31 GB / not usable 0
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              47695
  Free PE               14415
  Allocated PE          33280
  PV UUID               uti1WC-dIFW-4STS-v8Fr-VNiS-R8jx-fcCObn

  --- NEW Physical volume ---
  PV Name               /dev/md0
  VG Name
  PV Size               186.31 GB
  Allocatable           NO
  PE Size (KByte)       0
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               weSMyC-dFYc-wkQ1-Km5O-N5z5-68fK-85Lfuv
knossos:/home/heidi# vgextend /dev/knossos /dev/md0
  /var/lock/lvm/V_/dev/knossos: open failed: No such file or directory
  Can't get lock for /dev/knossos
knossos:/home/heidi# vgextend knossos /dev/md0
  Volume group "knossos" successfully extended
knossos:/home/heidi# vgdisplay
  --- Volume group ---
  VG Name               knossos
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  81
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               1
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               372.62 GB
  PE Size               4.00 MB
  Total PE              95390
  Alloc PE / Size       33280 / 130.00 GB
  Free  PE / Size       62110 / 242.62 GB
  VG UUID               xccB3F-8F8A-YzcP-jMNJ-rIkV-jxZ3-cueJwp

knossos:/home/heidi# pvmove /dev/hdb -v
    Finding volume group "knossos"
    Archiving volume group "knossos" metadata.
    Creating logical volume pvmove0
  mirror: Required device-mapper target(s) not detected in your kernel
knossos:/home/heidi# modprobe dm-mirror
knossos:/home/heidi# pvmove /dev/hdb -v
    Finding volume group "knossos"
    Archiving volume group "knossos" metadata.
    Creating logical volume pvmove0
    Moving 20480 extents of logical volume knossos/home
    Moving 12800 extents of logical volume knossos/cdimages
    Found volume group "knossos"
    Found volume group "knossos"
    Updating volume group metadata
    Creating volume group backup "/etc/lvm/backup/knossos"
    Found volume group "knossos"
    Found volume group "knossos"
    Found volume group "knossos"
    Loading knossos-pvmove0
  Volume group knossos metadata is inconsistent
  Volume group for uuid not found: xccB3F8F8AYzcPjMNJrIkVjxZ3cueJwpbFlPFexuk87RhLlyrADnO3fhvTt7RzVX
  /dev/md0: Checksum error
  Couldn't read volume group metadata.
  Volume group knossos metadata is inconsistent
  Volume group for uuid not found: xccB3F8F8AYzcPjMNJrIkVjxZ3cueJwpNvlkOKzchkxX5F4LINiZDQuxI2nMs0DT
    Checking progress every 15 seconds
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  Inconsistent metadata copies found - updating to use version 82
  /dev/hdb: Moved: 0.0%
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  /dev/hdb: Moved: 0.1%
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/hdb) called while suspended
  WARNING: dev_open(/dev/md0) called while suspended
  ABORTING: Can't find mirror LV in knossos for /dev/hdb