On Fri, Sep 24, 2010 at 12:01:35AM +0200, Alexander Skwar wrote: > > > > Suppose they gave you two huge lumps of storage from the SAN, and you > > mirrored them with ZFS. What would you do if ZFS reported that one of > > its two disks had failed and needed to be replaced? You can't do disk > > management with ZFS in this situation anyway because those aren't real > > disks. Disk management all has to be done on the SAN storage device. > > Yes. I was rather thinking about RAIDZ instead of mirroring.
I was just using a simpler example. > Anyway. Without redundancy, ZFS cannot do recovery, can > it? As far as I understand, it could detect block level corruption, > even if there's not redundancy. But it could not correct such a > corruption. > > Or is that a wrong understanding? That's correct, but it also should never happen. > If I got the gist of what you wrote, it boils down to how reliable > the SAN is? But also SANs could have "block level" corruption, > no? I'm a bit confused, because of the (perceived?) contra- > diction to the Best Practices Guide? :) The real problem is that ZFS was not designed to run in a SAN environment, that is one where all of the disk management and sufficient redundancy reside in the storage device on the SAN. ZFS certainly can't do any disk management in this situation. Error detection and correction is still a debatable issue, one that quickly becomes exceedingly complex. The decision rests on probabilities rather than certainties. -- -Gary Mills- -Unix Group- -Computer and Network Services- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
