Ok! now im with us! .. hmm. that makes more sense actually.. thank you for the time to explain that to me :) - Hide quoted text - On 7/10/07, Adam Leventhal wrote: > That's right. > > Adam > > On Tue, Jul 10, 2007 at 01:42:23PM -0400, Echo B wrote: > > What youre saying is that id have several raidz's to a zpool, and then > > when i needed more space, id make a new raidz, and add that to the > > zpool as well? > > > > On 7/10/07, Adam Leventhal wrote: > > >Hi Jason, > > > > > >Unfortunately, RAID doesn't work that way. It needs to distribute your data > > >over all the drives. If you were to have five drives and fill to three- > > >quarters capacity, adding an additional drive wouldn't give you the > > >reliability associated with RAID without redistributing the extant data. > > >I suppose "widening" a stripe would be possible, but it would be very very > > >difficult. > > > > > >You really have to commit to a unit of expansion and the number of failures > > >you want to be able to survive within a given unit. For example, you could > > >add drives in pairs and survive a single failure within each pair. My guess > > >is that it might make sense for you to use a relatively small RAID stripe > > >width (2+1 or 3+1) and then commit to adding drives 3 or 4 at a time. > > > > > >Adam > > > > > >On Tue, Jul 10, 2007 at 01:25:04PM -0400, Echo B wrote: > > >> I am a bit of a RAID noob in general. But the ultimate goal is to have > > >> one file system that can keep getting bigger and bigger and bigger.... > > >> > > >> My plan was to do something that isn't possible yet. Which was to add > > >> a drive or two and simply grow the raid-z by that capacity. > > >> > > >> > > >> On 7/10/07, Adam Leventhal wrote: > > >> >So your plan is to expand from a 4 + 1, say, to a 6 + 1 stripe? I don't > > >> >think that would be possible. I thought you might want to go from 4 + 1 > > >to > > >> >4 + 2 which is possible, but difficult. > > >> > > > >> >Adam > > >> > > > >> >On Tue, Jul 10, 2007 at 09:39:03AM -0400, Echo B wrote: > > >> >> Adam, > > >> >> Thanks for the reply! > > >> >> I do - I am setting up a Raid-Z 2 with 5 1TB disks. This is for my own > > >> >> small company, not a larger company with a larger budget. I currently > > >> >> house about 2TB of data. And within the year I expect my space needs > > >> >> to grow. Given that the hard drive investment just cost me nearly $2k, > > >> >> I cannot justify another $2k + in a hear when it is time to expand. > > >> >> Perhaps I am alone in this thought? If Raid-Z is so reliable for the > > >> >> data, it only makes sense that ppl wouldn't want to migrate off of it. > > >> >> As such, give them a batter growth path. > > >> >> I have a HW RAID controller that supports online growth (Areca > > >> >> ARC-1230) - and may well go with UFS2 because of growfs. > > >> >> > > >> >> I LOVE the feature set and capabilities of ZFS however and would much > > >> >> prefer to use that. > > >> >> > > >> >> Sincerely, > > >> >> > > >> >> :Jason > > >> >> > > >> >> On 7/10/07, Adam Leventhal wrote: > > >> >> >As has been mentioned on this forum, this would require a significant > > >> >> >change > > >> >> >to the way RAID-Z works. To my knowledge there is no such project at > > >> >> >present. > > >> >> >Do you have a use case where this is required? > > >> >> > > > >> >> >Adam > > >> >> > > > >> >> >On Sat, Jul 07, 2007 at 03:37:19PM -0400, Echo B wrote: > > >> >> >> Apologies for the blank message (if it came through). > > >> >> >> > > >> >> >> I have heard here and there that there might be in development a > > >plan > > >> >> >> to make it such that a raid-z can grow its "raid-z'ness" to > > >> >> >> accommodate a new disk added to it. > > >> >> >> Example: > > >> >> >> I have 4Disks in a raid-z[12] configuration. I am uncomfortably > > >low on > > >> >> >> space, and would like to add a 5th disk. The idea is to pop in > > >disk 5 > > >> >> >> and have the raid-z expand its feature set and free space to > > >> >> >> incorporate the 5th disk. > > >> >> >> > > >> >> >> Is there indeed such a thing in the works? Or in consideration? > > >> >> >> _______________________________________________ > > >> >> >> zfs-code mailing list > > >> >> >> zfs-code@opensolaris.org > > >> >> >> http://mail.opensolaris.org/mailman/listinfo/zfs-code > > >> >> > > > >> >> >-- > > >> >> >Adam Leventhal, Solaris Kernel Development > > >> >http://blogs.sun.com/ahl > > >> >> > > > >> > > > >> >-- > > >> >Adam Leventhal, Solaris Kernel Development > > >http://blogs.sun.com/ahl > > >> > > > > > > >-- > > >Adam Leventhal, Solaris Kernel Development http://blogs.sun.com/ahl > > > > > -- > Adam Leventhal, Solaris Kernel Development http://blogs.sun.com/ahl