> Yes the systems cited by the OP have nothing to do with RAID5, and in > fact are proprietary - definitely as in "non-standard", and I think > also none are open source. QNAP systems are Linux based and the underlying RAID system is based on mdadm. QNAP uses a newer version of mdadm that supports growing the array through disk swapping as well as raid level migration. I spent some time trying to understand how Drobo's "Beyond RAID" system works and it's nothing special. All they do essentially is partition the disks and make RAID arrays from within those partitions. If you had two 500GB disks and two 1TB disks, Drobo would partition the 1TB drives into 500GB chunks. then RAID the chunks. The first 500GB on all 4 drives would become a RAID-5 and the remaining partitions on the 1TB drives would become a RAID-1. Does Drobo use Linux under the hood? No idea. I've shied away from it because the whole "BeyondRAID" felt kinda hokey. -- Drew "Nothing in life is to be feared. It is only to be understood." --Marie Curie -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
