Fedora xen - May 2006 - FC5/Xen LVM resize question

Hi,

im playing around with Xen and FC5. There is one thing i dont get 
working. When i resize a logical volume in dom0 with lvextend, and 
this volume is used and mounted in a domU, it seems that the domU does 
not notice the new size of the partition until rebooted.
Should this work somehow without rebooting the domU, or is this the 
intended behavior?

I think, i could create a volume goup inside of a domU and add space 
to the domU by adding new block devices and adding their space to the 
volume group. But is this really a clever way of doing this, or are 
there any easier ways?

Thanks a lot,
Heinz


-- 
Heinz Deinhart
emp@nix.at

hi,
> im playing around with Xen and FC5. There is one thing i dont get 
> working. When i resize a logical volume in dom0 with lvextend, and this 
> volume is used and mounted in a domU, it seems that the domU does not 
> notice the new size of the partition until rebooted.
stupid question: did you resize the filesystem after extending the 
logical volume ?

http://www.die.net/doc/linux/HOWTO/LVM-HOWTO-9.html#ss9.9

this works for me:
- shutdown DomU
- extend LV in Dom0
- extend filesystem in Dom0
- restart (create) domU
> Should this work somehow without rebooting the domU, or is this the 
> intended behavior?
in theory, with a filesystem that allows online-resizing (see link 
above), it shouldn''t be necessary to shutdown DomU. But
haven''t tried yet.
> I think, i could create a volume goup inside of a domU and add space to 
> the domU by adding new block devices and adding their space to the 
> volume group. But is this really a clever way of doing this, or are 
> there any easier ways?
extending the logical volume in Dom0 is surely a more elegant approach.

cu

Hi,

On Mon, 29 May 2006, Rainer Fuegenstein wrote:
>> im playing around with Xen and FC5. There is one thing i dont get
working.
>> When i resize a logical volume in dom0 with lvextend, and this volume
is
>> used and mounted in a domU, it seems that the domU does not notice the
new
>> size of the partition until rebooted.
>
> stupid question: did you resize the filesystem after extending the logical 
> volume ?
yes, id did this. Even if its not resized, the changes are not even 
recognized by fdisk when i do a partprobe as David Robinson suggested.
> this works for me:
> - shutdown DomU
> - extend LV in Dom0
> - extend filesystem in Dom0
> - restart (create) domU
This works because the dom0 knows about the new size immediatly. But 
what i wanted to do is a resize without restarting the domU.
>> Should this work somehow without rebooting the domU, or is this the 
>> intended behavior?
> in theory, with a filesystem that allows online-resizing (see link above),
it
> shouldn''t be necessary to shutdown DomU. But haven''t
tried yet.
Well, i could not find any statement in the docu that really tells me 
that this would work. On the other side i could not find a statement 
that tells me it wont work. :)
>> I think, i could create a volume goup inside of a domU and add space to
the
>> domU by adding new block devices and adding their space to the volume 
>> group. But is this really a clever way of doing this, or are there any 
>> easier ways?
> extending the logical volume in Dom0 is surely a more elegant approach.
Agreed, this approach is not very elegant, but it seems its the only 
currently possible way to extend a domU fs without a restart.

ciao,
Heinz

-- 
Heinz Deinhart
heinz@nix.at