zfs discuss - Jun 2007 - Difference between "add" and "attach" a device?

Hi. I''ve been reading the ZFS admin guide, and I don''t
understand the distinction between "adding" a device and
"attaching" a device to a pool?

TIA
 
 
This message posted from opensolaris.org

Rick Mann wrote:
> Hi. I''ve been reading the ZFS admin guide, and I don''t
understand the distinction between "adding" a device and
"attaching" a device to a pool?
"attach" is used to create or add a side to a mirror.
"add" is to add a new top level vdev where that can be a raidz, mirror
or single device. Writes are spread across top level vdevs.

Hope that helps. Perhaps the zpool man page is clearer.

  Neil.

Hi Neil,

Neil.Perrin at Sun.COM: wrote:
> Rick Mann wrote:
> > Hi. I''ve been reading the ZFS admin guide, and I
don''t understand
> > the distinction between "adding" a device and
"attaching" a device
> > to a pool?
> 
> "attach" is used to create or add a side to a mirror.
> "add" is to add a new top level vdev where that can be a raidz,
mirror
> or single device. Writes are spread across top level vdevs.
That means that I can add more space to my raidz1 with "add"?

Thanks in advance :)


Greetz Cyron


--- fortune ---
Auch Ralleystreifen am Geh?use machen einen Computer mit Windows nicht
schneller.
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On 6/16/07, Ruben Cyron Wisniewski <cyron at winboard.org>
wrote:
> Hi Neil,
> That means that I can add more space to my raidz1 with "add"?
You can add another vdev, but you can''t change the size of an existing
vdev.  So if you''ve got five drives in a vdev, you can''t turn
that
into a 6-disk vdev, but you could add another five- or four- or
three-disk vdev just fine.  Actually changing the width of a vdev
would be very difficult, but as I understand it''s in the works.

Will