Hi, I would like to know what changes are made to the storage disk/lun/slice when it is added to a zfs pool? I am trying to relate to VxVM where the VTOC is changed. In otherwords, is there way to know if storage is part of ZFS just by examing any structure of the storage? Some documentation of zfs talks about a "physical virtual device" - physical and virtrual in one context - are these indicating "the physical device /disk/lun/slice"? Or is ther another virtual layering on top. The ZFS docs doesn''t seem to properly explain this. Or I havn''t seen all the relevant zfs docs. Thanks This message posted from opensolaris.org
Hello tester,
Tuesday, April 17, 2007, 10:46:52 AM, you wrote:
t> Hi,
t> I would like to know what changes are made to the storage
t> disk/lun/slice when it is added to a zfs pool? I am trying to
t> relate to VxVM where the VTOC is changed. In otherwords, is there
t> way to know if storage is part of ZFS just by examing any structure of the
storage?
If you add a slice then zfs won''t change vtoc.
However if you add an entire disk (in form of cXtYdZ - without a
slice) then zfs will put en EFI label on the disk.
By default zfs tools will first check if given slice/disk is used in a
system (mounted ufs file systems, part of other pool, etc.).
--
Best regards,
Robert mailto:rmilkowski at task.gda.pl
http://milek.blogspot.com
tester wrote:> Hi, > > I would like to know what changes are made to the storage disk/lun/slice when it is added to a zfs pool? I am trying to relate to VxVM where the VTOC is changed. In otherwords, is there way to know if storage is part of ZFS just by examing any structure of the storage?In addition to what Robert mentioned, ZFS places its configuration information in the on-disk format. There is no need to have a separate "private region" or "metadb" area in ZFS because it will not be used to encapsulate pre-existing slices. KISS. The ZFS on-disk format is available at the ZFS community site: http://www.opensolaris.org/os/community/zfs/ As part of adding ZFS and other features into Solaris, there are functions in the libdiskmgt library which can be used to determine if a disk has file systems in use. This provides additional use information over fstyp(1m). -- richard