On Wed, 27 Feb 2008, Peter Galvin wrote: > At the moment ZFS cannot expand a storage pool by single disk increments. > You could for example expand a RAIDZ pool by concatenating another RAIDZ set > to it, but not by adding a single disk.
Sure you can, "zpool add $poolname $device" > On 2/27/08 11:44 AM, "Edward Ned Harvey" <[EMAIL PROTECTED]> wrote: > > > The second one, what I'm referring to as "dualparity" is the ability to > > sustain 2 simultaneous disk failures without data loss. This is a function > > of the hardware raid controller, and not the filesystem. Am I making any > > bad assumptions here? I am not aware of any hardware raid controllers that > > can safely lose two disks at the same time, except the > > netapp/storevault/other enterprise filers. What I'm saying is, it's not > > supported like this on a sun xstore solaris zfs machine. Right? Definitely supports multiple simultaneous device failures. We did our initial testing on "whitebox" systems/arrays, then decided to use xstore for production. > > incrementally add disks, without degradation of redundancy or downtime. If > > I've got 6 disks in a dualparity configuration, controlled by hardware DP > > raid (usable capacity of 4 disks assuming no hotspare), I just slap in one > > more disk, and increase the size of my FS by 25%. No downtime, no > > degradation of redundancy. Perhaps the system runs slow for a couple hours. > > This too is not supported in the sun xstore solaris zfs configuration, > > right? Definitely supported, no need to recompute. > > I don't think it's fair to say it's supported in OSX. In OSX, you cannot > > format and create a ZFS filesystem, and you can only mount it read-only. > > Although read/write variations exist, they are very immature at best. You can definitely create a ZFS filesystem in OSX, as of Tiger I believe, can't say I run it daily, but we did a test just to qualify this feature. > > > > Same is true for Linux. Although it's open source, it can't be compiled in > > the linux kernel any time soon. Because it's written under CDDL, which > > conflicts with GPL. See here: http://en.wikipedia.org/wiki/ZFS#Platforms Fair enough. I don't really know much about Linux to be honest. Also -- ZFS does not need battery backup to deal with hardware crashes mid-write. There is a lengthy presentation out there which describes this in detail. -rob _______________________________________________ bblisa mailing list [email protected] http://www.bblisa.org/mailman/listinfo/bblisa
