[OpenIndiana-discuss] ZfS migration scenario including zvols

[Timothy Coalson]

On Mon, Apr 15, 2013 at 5:53 AM, Sebastian Gabler <sequoiamobil at gmx.net>wrote:

> I have also learned that there are obviously methods to prevent a
> replicated stream from mounting. But I still wonder how exactly I should
> have proceeded here to achieve that the replicated data could not be
> tempered with while waiting for their repatriation.
>

Snapshots are inherently read-only, and you can only send snapshots.  The
only tampering that could be done (assuming a properly working system) is
to destroy, create, or rename snapshots, which hopefully you don't have to
worry about being done without your knowledge/request.  Changes made in the
filesystem while it is waiting to be sent to its final location would only
carry over if you took another snapshot on the temporary FS, and
transferred that, which you would not have a reason to do if you don't want
those changes.

There is also the readonly property of filesystems, you could set that
before the first send, and unset it only after it is in the final location.
 Note, however, that this doesn't prevent the creation/deletion/renaming of
snapshots.  It is therefore largely irrelevant in this case, it would only
prevent someone from writing to it if they stumbled upon its temporary
location (these writes would be discarded on transfer anyway, since you
send the snapshot, so it only serves to prevent surprise to the user who
tried to use it when they shouldn't have).

Tim