[CentOS] LVM Resizing Problem

[Marko A. Jennings]

On Thu, May 3, 2007 2:06 am, Al Sparks wrote:
>
> --- Matt Hyclak <hyclak at math.ohiou.edu> wrote:
>
>> On Wed, May 02, 2007 at 06:59:26PM -0700, Al Sparks enlightened us:
>> > 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?
>>
>> Did you resize the filesystem, too?
>>
>> Matt
>
> Nope.  How do you do that?
>    === Al

Take a look at http://tldp.org/HOWTO/LVM-HOWTO/ .  Lots of good examples.