On Wed, Jul 9, 2014 at 6:44 AM, Gabriele Bulfon via illumos-discuss < [email protected]> wrote:
> Hi, > > as an experiment. > > Let's say I have a zfs fs shared as an NFS resource to another illumos > client. > Let's say I have created a 152GB file on this resrouce. > Let's say I have added the file as a lofi dev on the NFS server, and > created a 512GB zpool on it. > Finally, let's say I have added the file as a lofi dev on the NFS client > too. > > Now I can export / import the pool both from the NFS server, and the NFS > client. > > Obviously I can't import the pool from both machines. > > But...what if one would "import -f -o readonly=on" and the other would > import -f read/write? > Would it be possible? > This would let me zfs send the client pool to the lofi pool on the NFS > share, while have the server > be able to read the contained files. > > Is it safe? > The readonly import may see data corruption, because the read/write system could free and then overwrite data that the readonly system thinks is referenced. That said, it will probably appear to mostly work. But it is not a production-ready solution by any means. I'd also note that on the server you have a pool on top of another pool on a single system. This also does not work in general; there are a few deadlocks you could hit, e.g. related to the spa_namespace_lock. --matt > > Gabriele. > > > > > *illumos-developer* | Archives > <https://www.listbox.com/member/archive/182179/=now> > <https://www.listbox.com/member/archive/rss/182179/21175069-3b70c3b5> | > Modify <https://www.listbox.com/member/?&;> Your Subscription > <http://www.listbox.com> > > > *illumos-discuss* | Archives > <https://www.listbox.com/member/archive/182180/=now> > <https://www.listbox.com/member/archive/rss/182180/21175667-2019e749> | > Modify > <https://www.listbox.com/member/?&;> > Your Subscription <http://www.listbox.com> > ------------------------------------------- illumos-discuss Archives: https://www.listbox.com/member/archive/182180/=now RSS Feed: https://www.listbox.com/member/archive/rss/182180/21175430-2e6923be Modify Your Subscription: https://www.listbox.com/member/?member_id=21175430&id_secret=21175430-6a77cda4 Powered by Listbox: http://www.listbox.com
