[CentOS] LVM Resizing Problem

Thu May 3 01:59:26 UTC 2007
Al Sparks <data345 at yahoo.com>

I'm new to lvm.  I decided to decrease the space of a logical volume.
So I did a:
   $ df -m
   Filesystem           1M-blocks      Used Available Use% Mounted on
   /dev/mapper/VolGroup00-LogVol00
                             1953       251      1602  14% /
   /dev/sda2                  494        21       448   5% /boot
   tmpfs                     1014         0      1014   0% /dev/shm
   /dev/mapper/VolGroup00-LogVol05
                            48481      6685     39295  15% /home
   /dev/mapper/VolGroup00-LogVol03
                              961        18       894   2% /tmp
   /dev/mapper/VolGroup00-LogVol01
                             7781      2051      5329  28% /usr
   /dev/mapper/VolGroup00-LogVol02
                             5239       327      4642   7% /var



    $ sudo lvm lvreduce -L -1000M /dev/VolGroup00/LogVol05
    Rounding up size to full physical extent 992.00 MB
    WARNING: Reducing active and open logical volume to 47.91 GB
    THIS MAY DESTROY YOUR DATA (filesystem etc.)
  Do you really want to reduce LogVol05? [y/n]: y
    Reducing logical volume LogVol05 to 47.91 GB
    Logical volume LogVol05 successfully resized


   $ df -m
   Filesystem           1M-blocks      Used Available Use% Mounted on
   /dev/mapper/VolGroup00-LogVol00
                             1953       251      1602  14% /
   /dev/sda2                  494        21       448   5% /boot
   tmpfs                     1014         0      1014   0% /dev/shm
   /dev/mapper/VolGroup00-LogVol05
                            48481      6685     39295  15% /home
   /dev/mapper/VolGroup00-LogVol03
                              961        18       894   2% /tmp
   /dev/mapper/VolGroup00-LogVol01
                             7781      2051      5329  28% /usr
   /dev/mapper/VolGroup00-LogVol02
                             5239       327      4642   7% /var

Note that "df" shows the same size available.  This probably means
that the 2 "systems" aren't talking to each other (or my lvm command
failed).

When I rebooted, things failed, going into "repair filesystem" mode.
I tried
   fsck /dev/VolGroup00/LogVol05 

but after awhile, it started giving block errors, specifically
   "Error reading block <block-number> (Invalid argument) while doing inode scan.  Ignore error<y>?

I held down the <Enter> key for awhile in hopes that I'd be able to
get through the errors, but no joy.  I finally cancelled the thing.

I can rebuild the server, it's no big deal.  In fact the logical
volume that went bad isn't a big deal data wise, and I shouldn't need
that data to bring up the server itself.  I shouldn't need to mount
it.  So can I still save this?
   === Al