[PLUG] Accessing individual external hard drives in the same enclosure

[Keith Lofstrom]

On Thu, Sep 28, 2017 at 06:23:28PM -0700, Rich Shepard wrote:
>   I have a HornetTek dual-bay external hard drive case (SATA II and USB 2
> which are adequate for my needs). 

My guess is that the dual drive enclosure requires
special windoze software to switch something in the
controller chip in the drive.  By now, some obsessive
Linux coder might have reverse engineered that and 
made a Linux driver for it.  That driver will be alpha
code, unlikely to find it's way into a distro.  

But there's a good reason why nobody smart enough to
write a driver would bother:

A question you should ask is whether you mind losing two
drives rather than one if the (presumably supercheap)
HornetTek power supply fails, loses regulation and zaps
the 5V drives with (say) unregulated 10 volt power?

That is why an impulse-buy dual bay "drive toaster" sits
in an unopened box on my shelf.  Partly because I was
too lazy to return it, partly to remind me of unintended 
consequences discovered by subsequent contemplation. 

Running two separate enclosures costs a little more and
may burn more power when both are operating, but burns
less power when only one enclosure is powered at a time.

If I need to make an operating-system-mediated drive-to-
drive copy, two enclosures is twice as fast.  With low
bandwidth USB2, that matters a lot.  So, the total
energy per copy is less with two enclosures.

Something to ponder.  Small acknowledged mistakes can
forestall bigger ones.

Keith

-- 
Keith Lofstrom          keithl at keithl.com