libvirt users - May 2010 - Mount options for fs type storage pools?

Hi all,

Presently writing up "Storage Pool" docs for the Fedora Virtualisation
Guide.  (using both virsh and virt-manager)

Having trouble finding out how to specify mount options for fs type 
storage pools.

For example:

   # virsh pool-define-as guest_images_fs fs - - /dev/sdc1 -
"/guest_images"
   Pool guest_images_fs defined

   # virsh pool-build guest_images_fs
   Pool guest_images_fs built

   # virsh pool-start guest_images_fs
   Pool guest_images_fs started

   # mount | grep guest_images
   /dev/sdc1 on /guest_images type ext4 (rw)
   #

Notice that /guest_images is mounted with default options.  Nothing 
wrong with that, but lets say the SysAdmin has a need to pass specific 
mount options.  (ie journal_checksum, or noatime, or nodiratime, etc)

Checked the virStorageBackendFileSystemMount() function in present git 
master, and it doesn't look like mount options are considered for 
anything other than Gluster?

How to do it, or is it best to not use libvirt to manage the mounting of 
this type of storage when options are needed?

Regards and best wishes,

Justin Clift

-- 
Salasaga  -  Open Source eLearning IDE
               http://www.salasaga.org

On 05/31/2010 09:54 AM, Justin Clift wrote:
> Hi all,
> 
> Presently writing up "Storage Pool" docs for the Fedora
Virtualisation
> Guide.  (using both virsh and virt-manager)
> 
> Having trouble finding out how to specify mount options for fs type 
> storage pools.
> 
> For example:
> 
>    # virsh pool-define-as guest_images_fs fs - - /dev/sdc1 -
"/guest_images"
>    Pool guest_images_fs defined
> 
>    # virsh pool-build guest_images_fs
>    Pool guest_images_fs built
> 
>    # virsh pool-start guest_images_fs
>    Pool guest_images_fs started
> 
>    # mount | grep guest_images
>    /dev/sdc1 on /guest_images type ext4 (rw)
>    #
> 
> Notice that /guest_images is mounted with default options.  Nothing 
> wrong with that, but lets say the SysAdmin has a need to pass specific 
> mount options.  (ie journal_checksum, or noatime, or nodiratime, etc)
> 
> Checked the virStorageBackendFileSystemMount() function in present git 
> master, and it doesn't look like mount options are considered for 
> anything other than Gluster?
> 
> How to do it, or is it best to not use libvirt to manage the mounting of 
> this type of storage when options are needed?
> 
Can't find the email thread, but I believe this has been explicitly
rejected in the past. Allowing arbitrary option passthrough could
conflict with a future libvirt version if we alter the mount command
line, among other supportability reasons (though we have backtracked a
bit on that stance WRT the qemu emulator command line, but there is much
more at stake in that case).

If users need special mount options, their best option is to manually
configure the mount, then create a directory pool pointing at the mount dir.

- Cole