I'm trying to use LVM together with md. I know you guys don't
recommend this combination, but I need it to get good performance
from our disks plus some protection. This combination used to work
with 0.3, but stop working with the new 1.0.7. I think the problem
is
that after rebooting LVM has problem figuring out that it needs to
use
md0-3 and not their corresponding part (/dev/sd?).
Have you done this before?
I'm adding the series of commands we used to create the volume, plus
the status after we reboot the machine.
CREATING THE VOLUME
# cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid5] [multipath]
read_ahead 1024 sectors
md4 : active raid0 md3[3] md2[2] md1[1] md0[0]
143372288 blocks 512k chunks
md3 : active raid1 sdi[1] sdh[0]
35843584 blocks [2/2] [UU]
md2 : active raid1 sdg[1] sdf[0]
35843584 blocks [2/2] [UU]
md1 : active raid1 sde[1] sdd[0]
35843584 blocks [2/2] [UU]
md0 : active raid1 sdc[1] sdb[0]
35843584 blocks [2/2] [UU]
unused devices: <none>
#dd bs=256k if=/dev/zero of=/dev/md0 count=1000
#dd bs=256k if=/dev/zero of=/dev/md1 count=1000
#dd bs=256k if=/dev/zero of=/dev/md2 count=1000
#dd bs=256k if=/dev/zero of=/dev/md3 count=1000
# pvcreate /dev/md0
pvcreate -- physical volume "/dev/md0" successfully created
# pvcreate /dev/md1
pvcreate -- physical volume "/dev/md1" successfully created
# pvcreate /dev/md2
pvcreate -- physical volume "/dev/md2" successfully created
# pvcreate /dev/md3
pvcreate -- physical volume "/dev/md3" successfully created
# vgcreate vg01 /dev/md[0-3]
vgcreate -- INFO: using default physical extent size 32 MB
vgcreate -- INFO: maximum logical volume size is 2 Terabyte
vgcreate -- doing automatic backup of volume group "vg01"
vgcreate -- volume group "vg01" successfully created and activated
# pvscan
pvscan -- reading all physical volumes (this may take a while...)
pvscan -- ACTIVE PV "/dev/md0" of VG "vg01" [34.12
GB / 34.12 GB free]
pvscan -- ACTIVE PV "/dev/md1" of VG "vg01" [34.12
GB / 34.12 GB free]
pvscan -- ACTIVE PV "/dev/md2" of VG "vg01" [34.12
GB / 34.12 GB free]
pvscan -- ACTIVE PV "/dev/md3" of VG "vg01" [34.12
GB / 34.12 GB free]
pvscan -- inactive PV "/dev/md4" of VG "vg01" [34.12 GB / 34.12 GB
free]
pvscan -- WARNING: physical volume "/dev/sdb" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdc" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdd" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sde" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdf" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdg" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdh" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdi" belongs to a meta device
pvscan -- total: 13 [170.92 GB] / in use: 13 [170.92 GB] / in no VG:
0 [0]
#lvcreate -i 4 -I 512 -L 130G -n lv01 vg01
lvcreate -- doing automatic backup of "vg01"
lvcreate -- logical volume "/dev/vg01/lv01" successfully created
# vgdisplay -v
--- Volume group ---
VG Name
vg01
VG Access
read/write
VG Status
available/resizable
VG #
0
MAX LV
256
Cur LV
1
Open LV
0
MAX LV Size
2 TB
Max PV
256
Cur PV
4
Act PV
4
VG Size
136.50 GB
PE Size
32 MB
Total PE
4368
Alloc PE / Size 4160 / 130 GB
Free PE / Size 208 / 6.50
GB
VG UUID
tXh4cm-QVz6-bT6a-yLRl-PnHc-cY16-72aPfp
--- Logical volume ---
LV Name
/dev/vg01/lv01
VG Name
vg01
LV Write Access read/write
LV Status
available
LV #
1
# open
0
LV Size
130 GB
Current LE
4160
Allocated LE
4160
Stripes
4
Stripe size (KByte) 512
Allocation
next free
Read ahead sectors 1024
Block device
58:0
--- Physical volumes ---
PV Name (#)
/dev/md0 (1)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/md1 (2)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/md2 (3)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/md3 (4)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
AFTER REBOOT
# pvscan
pvscan -- reading all physical volumes (this may take a while...)
pvscan -- inactive PV "/dev/md0" of VG "vg01" [34.12 GB / 1.62 GB free]
pvscan -- inactive PV "/dev/md1" of VG "vg01" [34.12 GB / 1.62 GB free]
pvscan -- inactive PV "/dev/md2" of VG "vg01" [34.12 GB / 1.62 GB free]
pvscan -- inactive PV "/dev/md3" of VG "vg01" [34.12 GB / 1.62 GB free]
pvscan -- inactive PV "/dev/md4" of VG "vg01" [34.12 GB / 1.62 GB free]
pvscan -- WARNING: physical volume "/dev/sdb" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdc" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdd" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sde" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdf" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdg" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdh" belongs to a meta device
pvscan -- WARNING: physical volume "/dev/sdi" belongs to a meta device
pvscan -- total: 13 [170.92 GB] / in use: 13 [170.92 GB] / in no VG:
0 [0]
[root@sculpin root]# vgdisplay -v
--- Volume group ---
VG Name
vg01
VG Access
read/write
VG Status
available/resizable
VG #
0
MAX LV
256
Cur LV
1
Open LV
0
MAX LV Size
2 TB
Max PV
256
Cur PV
4
Act PV
4
VG Size
136.50 GB
PE Size
32 MB
Total PE
4368
Alloc PE / Size 4160 / 130 GB
Free PE / Size 208 / 6.50
GB
VG UUID
tXh4cm-QVz6-bT6a-yLRl-PnHc-cY16-72aPfp
--- Logical volume ---
LV Name
/dev/vg01/lv01
VG Name
vg01
LV Write Access read/write
LV Status
available
LV #
1
# open
0
LV Size
130 GB
Current LE
4160
Allocated LE
4160
Stripes
4
Stripe size (KByte) 512
Allocation
next free
Read ahead sectors 1024
Block device
58:0
--- Physical volumes ---
PV Name (#)
/dev/sdc (1)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/sde (2)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/sdg (3)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
PV Name (#)
/dev/sdi (4)
PV Status
available / allocatable
Total PE / Free PE 1092 / 52
