On Jul 22, 2010, at 2:41 PM, Miles Nordin <car...@ivy.net> wrote: >>>>>> "sw" == Saxon, Will <will.sa...@sage.com> writes: > > sw> 'clone' vs. a 'copy' would be very easy since we have > sw> deduplication now > > dedup doesn't replace the snapshot/clone feature for the > NFS-share-full-of-vmdk use case because there's no equivalent of > 'zfs rollback' > > > I'm tempted to say, ``vmware needs to remove their silly limit'' but > there are takes-three-hours-to-boot problems with thousands of Solaris > NFS exports so maybe their limit is not so silly after all. > > What is the scenario, you have? Is it something like 40 hosts with > live migration among them, and 40 guests on each host? so you need > 1600 filesystems mounted even though only 40 are actually in use? > > 'zfs set sharenfs=absorb <dataset>' would be my favorite answer, but > lots of people have asked for such a feature, and answer is always > ``wait for mirror mounts'' (which BTW are actually just-works for me > on very-recent linux, even with plain 'mount host:/fs /fs', without > saying 'mount -t nfs4', in spite of my earlier rant complaining they > are not real). Of course NFSv4 features are no help to vmware, but > hypothetically I guess mirror-mounting would work if vmware supported > it, so long as they were careful not to provoke the mounting of guests > not in use. The ``implicit automounter'' on which the mirror mount > feature's based would avoid the boot delay of mounting 1600 > filesystems. > > and BTW I've not been able to get the Real Automounter in Linux to do > what this implicit one already can with subtrees. Why is it so hard > to write a working automounter? > > The other thing I've never understood is, if you 'zfs rollback' an > NFS-exported filesystem, what happens to all the NFS clients? It > seems like this would cause much worse corruption than the worry when > people give fire-and-brimstone speeches about never disabling > zil-writing while using the NFS server. but it seems to mostly work > anyway when I do this, so I'm probably confused about something.
To add to Miles' comments, what you are trying to accomplish isn't possible via NFS to ESX, but could be accomplished with iSCSI zvols I believe. If I understand you can thin-provision a zvol and clone it as many times as you wish and present all the clones over iSCSI. Haven't tried it myself, but would be worth testing. -Ross _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
