Thanks Matt: I have been trying my best to create 3 (12TB each) servers with dragonflybsd with HAMMER to avoid zfs, but from what I read below, I have no option than going for a freebsd+zfs (with nanobsd).
I indeed enjoyed being here and appreciate very courteous and supportive adopters and developers of dfbsd. I shall be around anyway ;-) On 12/27/11, Matthew Dillon <dil...@apollo.backplane.com> wrote: > Definitely not hammer volume add, that's too experimental. Soft-raid > is a bit of a joke in my view, since it typically ties you to a > particular motherboard and bios (making it difficult to physically > move disks to another machine if the mobo or psu dies), and as with > all soft-raid systems any sort of power failure during a write is > likely to cause unrecoverable data loss. Honestly I don't know of a > single system that ever had fewer failures with soft-raid than with > single disks w/ near real-time backup streams. > > For HAMMER1 the best set-up is either a real raid system or no raid > at all and a master/slave server setup, depending on what is being > served. Unfortunately nothing in BSD really approaches Linux's block > level clustering and VZ container system at the moment (which is a bit > of > a joke too when it comes to multiple failover events but works pretty > well otherwise). > > If you have a small system then there's no point running RAID. If you > have a larger system then there's no point running a single server. > And running RAID on multiple servers eats a lot of power so for storage > needs less than what conveniently fits on one or two disks there's no > point running RAID at all... you run redundant servers instead and use > a SSD as a caching layer in front of the slower hard drive. > > For larger single-volume storage needs multiple real raid system for > primary and backup with all the insundry fallback hardware is the only > way to go. Soft-raid won't cut it. > > -Matt > Matthew Dillon > <dil...@backplane.com> >
