Re: [tlug] LVM2 and resizing partition

[Gernot Hassenpflug <aikishugyo@example.com>]

On Thu, Nov 5, 2009 at 11:21 AM, Edward Middleton <emiddleton@example.com> wrote:
> Gernot Hassenpflug wrote:
>>
>>   I want to reduce the partition to make space for another one behind
>> it (eventually). The partition size is 502GiB and I want to reduce it
>> to about 200GiB. There are two logical volumes in one logical volume
>> group: one is 6.3GiB, the other fills the rest of the space.
>>
> I don't know of an easy way to fix your problem.
>
> What you have done doesn't really help.  You have reduce the number of
> physical extents allocated to the LogVol00 logical volume,  from the
> 500G VolGroup00 volume group, but you don't know where in the volume
> group (i.e. the partition) they are allocated.

Thanks for the reply Edward. OK, I discovered this little titbit just now.

> If you had used multiple partitions to make your volume group[1],  you
> could have moved extents of each partition using pvmove and
> repartitioned that way.

I see. I'll keep that in mind. Unfortunately, I didn't know this and
just let CentOS do its default install on the existing partition
space.

> My advice would be to get another hard drive add it to the volume group,
> move all extents to the new drive then create multiple smaller
> partitions.  If you have enough free space on another partition  you
> could also resize and use it instead of adding another drive but this
> will be an very slow process.  Just found this[2] which also gives
> basically the same advice.

OK, will try this. I was attempting to reduce to the amount the OS
actually takes, but it is "fragmented" so I would have needed a
gigantic hard drive, in which case I might as well just get another
one anyway! I'll see what I can do with your suggestion, using a USB
drive.

Many thanks,
Gernot