Raiding a USB chain possible?

Lord_Devi · 04-02-2007, 08:32 PM

A friend of mine brought up an interesting idea I haven't been able to really find much information about. Essentially he proposed getting many harddrives, say 10, and using sata-2-usb connectors on the rear(I believe each brick would then need an external power source), and then using software raid to jbod the usb chained harddrives.

How feasable an idea is this? I'm assuming it would go pretty slow, but if it is merely for mass storage, a certain slowness would be tolerable..

macemoneta · 04-02-2007, 09:27 PM

It will work fine. It won't be slow, unless you use a USB hub. Put every drive on its own USB 2.0 port (USB PCI cards are cheap), and each drive will have 35MB/s bandwidth. You'll saturate your bus in no time.

I have 4 160GB USB 2.0/Firewire drives daisy chained via Firewire (one of the advantages of Firewire over USB) and connected to my laptop as a RAID-5 array. It runs 35-40MB/s continuous, no problem.

This is one of the really cool aspects of software RAID on Linux; any block devices can be RAIDed.