[Fedora-xen] FC5/Xen LVM resize question

[Heinz Deinhart]

On Fri, 12 May 2006, David Robinson 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. ext2online does nothing, fdisk 
>> reports the old size.
>
> the kernel wouldn't be aware of the size change hence why fdisk reports the 
> old size. try running "partprobe" - it basically tells the kernel to reread 
> the partition table

I tried this, but partprobe does not seem to work.

But should it? In my testcase there are no partition tables at all. I 
export a lvm volume as partition:
   lvcreate -L1g vg0 part1
   xm block-attach fc5dom phy:vg0/part1 /dev/hdp rw
Then, inside of the domU, i do:
   mount /dev/hdp /mnt/tmp

So, if i don't miss anything, then there is no partition table that 
can be reloaded.


But then, i tried to create a partition table and mount e.g. hdp1 and 
it did not work either. Even after calling partprobe, i was not able 
to grow the filesystem and fdisk reports the old size.

In all cases everything works after rebooting the domU, so i know that 
i did not fail doing the lvextend. Is there anything else i can try?

Can it be that using LVM volumes and growing them on the fly for domUs 
is not supported, or could it be a bug?

Thanks a lot,
Heinz

-- 
Heinz Deinhart
heinz at nix.at