Re: [tlug] Hard Drive Failure (Was: Help! Total hardware failure)

[Curt Sampson <cjs@example.com>]

On 2008-09-14 19:54 +0900 (Sun), Mark Makdad wrote:

> Either way, for a 40,000 JPY investment, when a new drive will cost
> you 10,000 JPY anyway, I'd say it's a fantastic deal. It has 2 drives
> included-- half the cost of the hardware are the drives themselves.

Actually, 500 GB drives are currently between 6,000 and 7,000 yen each.
So you could set up basically the same NAS for 14,000 yen plus a bit of
time to set up RAID and Samba on a desktop comptuter. If you're missing
the desktop computer, that would set you back another 30,000 yen or so
for a very basic configuration (motherboard with built-in video, cheap
CPU, a half gig of RAM, and case).

On 2008-09-14 21:20 +0900 (Sun), Dave M G wrote:

> I was wondering about the feasibility of buying a second drive, and then 
> doing a complete copy once a day.

If you're going to buy a second drive, as others have mentioned, you
might just as well use it to mirror your current drive, and then you
don't have to worry about doing the copies; it's automatic and instant.
Your data loss window will also be smaller.

On 2008-09-14 22:46 +0900 (Sun), Mark Makdad wrote:

> The issue here is that the NAS box is hardware RAID, so it tends to
> be slightly faster than software RAID. At least theoretically. Anyone
> want to take me on there?

It's not likely at all that the NAS box is hardware RAID; it's most
likely just a cheap Linux or BSD system using the OS software RAID
facilities and running Samba.

Software RAID on a PC is almost certain to be faster than any low-priced
(i.e., under tens of thousands of dollars) external RAID setup, both
because the PC will usually have far, far more processing power than the
external box, and because, at least for stuff on the PC, you don't need
all the overhead of network procotocols.

Do a quick test by dd'ing a file from your NAS to /dev/null. If you're
not getting 80-90 MB/sec. read rates, you could do better just by
buying a couple of 7000 yen drives and plopping them directly into your
machine.

cjs
-- 
Curt Sampson       <cjs@example.com>        +81 90 7737 2974   
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