Ross, Nate, Tony, thanks for your promptly response

On Mon, Jul 28, 2008 at 2:51 PM, nate <centos@linuxpowered.net> wrote:

Eduardo Grosclaude wrote:

> 4) Rebooted the installed system. Now "Duplicate PV" shows at boot. Honestly

To me it sounds likely that the raid controller is shitty and
is presenting two sets of devices to the OS, one likely being
the "RAID" device and the other a more generic device(s).

What does 'dmesg' say? Do you see more devices than you think
you should have on the system?

dmesg says nothing about this, the message only appears at console when booting or otherwise using the PVs:

[root@myserver ~]# pvs
Found duplicate PV 8D7K2wg15HqD0l9HxZCz7QlDfpqJOhXT: using /dev/sdb2 not /dev/sda2
PV         VG         Fmt Attr PSize   PFree
/dev/sdb2 VolGroup00 lvm2 a-   465,62G    0

[root@myserver ~]# lvs
Found duplicate PV 8D7K2wg15HqD0l9HxZCz7QlDfpqJOhXT: using /dev/sdb2 not /dev/sda2
LV       VG         Attr   LSize   Origin Snap% Move Log Copy%
LogVol00 VolGroup00 -wi-ao 150,00G
LogVol01 VolGroup00 -wi-ao   1,94G
LogVol02 VolGroup00 -wi-ao 313,69G

[root@myserver ~]# sfdisk -d
# tabla de particiones de /dev/sda
unit: sectors

/dev/sda1 : start=       63, size=   208782, Id=83, bootable
/dev/sda2 : start=   208845, size=976543155, Id=8e
/dev/sda3 : start=        0, size=        0, Id= 0
/dev/sda4 : start=        0, size=        0, Id= 0
# tabla de particiones de /dev/sdb
unit: sectors

/dev/sdb1 : start=       63, size=   208782, Id=83, bootable
/dev/sdb2 : start=   208845, size=976543155, Id=8e
/dev/sdb3 : start=        0, size=        0, Id= 0
/dev/sdb4 : start=        0, size=        0, Id= 0

Awful--I expected to see just one device :P

> There might be a disk from an old RAID1 set in there.
Don't think so, this machine was integrated here with new materials.

Oops... system-config-lvm shows under 'Uninitialized entities':
/dev/sda
     -> part 1
     -> part 2
     -> unpartitioned space
/dev/sdb
     -> part 1
     -> unpartitioned space
These shouldn't be appearing as two discs in the first place-- but anaconda said I only had one unit...
Anyway, why the asymmetry? Did I screw the RAID volume somehow? Or did I install plain on sda and this RAID never worked as such? :P
The machine BIOS correctly describes the RAID volume at start. Doesn't It smell like fake RAID?
Should I declare sdb invalid to the firmware program so as to force resync?
Thanks again
--
Eduardo Grosclaude
Universidad Nacional del Comahue
Neuquen, Argentina