[linux-lvm] SCSI/LVM problems after power outage

[Dave Wapstra]

On 09 May, 2001 at 21:26:29 +0000, Heinz J. Mauelshagen <Mauelshagen at sistina.com> wrote:
> On Wed, May 09, 2001 at 08:14:16PM +0200, Dave Wapstra wrote:
> > On 09 May, 2001 at 09:35:10 +0000, Heinz J. Mauelshagen <Mauelshagen at sistina.com> wrote:
> > > 
> > > Steps needed (crossing your fingers that the flaky drive can still stand this):
> > > 
> > > - install or use an additional drive of at least the size of the flaky one
> > > - pvcreate that drive
> > > - vgextend the VG by it
> > > - pvmove /dev/FlakyDrive
> > > - wait until pvmove is done
> > > - vgreduce VG /dev/FlakyDrive
> > 
> > I'm trying to backup the data that is still available (backup was a
> > thing that was still in progress... :) ) 
> > 
> > pvmove is not really happy with the current situation.
> 
> I don't understand you here.
> Did you try the above steps and something failed?

Yes, the pvmove command didn't finish succesfully.  Unfortunately, I
haven't saved the output, so I cannot show you what the exact messages were.

> > Can I just do "vgreduce ftp /dev/sdc" after I finished rescueing most of the data?
> > 
> 
> Sure.
> In case you've got a backup, you could remove or reduce LVs so that *no*
> PEs are allocated on /dev/sdc.
> You can check with "pvdisplay -v /dev/sdc" which LV(s) have PEs allocated
> on that PV and run lvremove/lvreduce in order to free that PV.
> 
> Once pvdisplay tells you that no PEs are allocated (Allocated PE 0) you
> can run "vgreduce VGName /dev/sdc".

Actually, my colleage already removed the complete volume configuration
and started from scratch.

The thing is, I've had this problem before.  It seemed that a power
failure caused us some troubles. However, after re-initialising the
disks (pv/vg/lv), creating a new filesystem and restoring the backup,
everything is fine again.

Even /dev/sdc is not complaining at all.

# pvdisplay /dev/sdc
--- Physical volume ---
PV Name               /dev/sdc
VG Name               ftp
PV Size               8.43 GB / NOT usable 1.34 MB [LVM: 129 KB]
PV#                   2
PV Status             available
Allocatable           yes (but full)
Cur LV                1
PE Size (KByte)       4096
Total PE              2159
Free PE               0
Allocated PE          2159
PV UUID               none

Seems the disk is full, and no SCSI messages in the log files (?)

After the new filesystem has been created, the system was powered down
(switched off) twice to check if this is trigerring anything. In both
cases fsck successfully restored any errors.

I'm not sure if this is a hardware problem or not. The disk seems to
work fine, however in some situations SCSI errors occur.

Any suggestions on testing the disk for hardware problems are appreciated.
(dd if=/dev/sdc of=/dev/null ?)


-Dave

-- 
Dave Wapstra
dave at xs4all.nl