Re: [dm-devel] Resizing multipath maps: reload ioctl failed: Invalid argument

["Jun'ichi Nomura" <j-nomura ce jp nec com>]

Hi,

Domenico Viggiani wrote:
>  http://www.redhat.com/archives/dm-devel/2007-August/msg00188.html
> 
> Is it confirmed that online resizing with multipath is impossible?
> 
> If yes, in my opinion, this is a serious limitation to a serious enterprise
> use of Linux.

I'm trying to find a kernel fix for this issue.

I'll post patches for 2.6.23 kernel.
(But it should be easily adaptible to other versions.)

I have tested the patches mainly on modified LVM2 (i.e. resizing
mirror LV).
Since I don't have resizable multipath device,
if you are interested in testing, it would be much appreciated.

Alternative is to use dmsetup directly, as Aaron suggested.
But there is a corner case that if all paths are down before
'dmsetup suspend', I/O errors will occur regardless of
queue_if_no_path setting.

Thanks,
-- 
Jun'ichi Nomura, NEC Corporation of America