On Sun, 15 Mar 2015 18:40:05 +0000, Martin Gregorie wrote:
On Sun, 15 Mar 2015 15:41:04 +0000, Folderol wrote:
On Sun, 15 Mar 2015 13:34:16 -0000 Daniel James
wrote:
In article , Tim Watts wrote:
I believe the point was: what happens when the PSU melts and dumps
mains to the output and blows your NAS to tiny weeny bits?
That's certainly the right question to be asking.
I thought someone had wanted the NAS and it's PSU to be usable after
the fire, but rereading today I can't find it.
I would hope the NAS had some serious crowbar protection on its
incoming DC in.
Indeed so ... and on the ethernet and USB connectors, though the power
input is more likely to cause trouble.
Ethernet is pretty bomb-proof by design.
USB is very much a weak point. There nothing bar a simple polyfuse
protecting the +5V line, and the I/O ones are totally vulnerable.
Indeed, recently I read about some b**tard designing a device -
masquerading as memory stick - that keeps pulsing these with a very
high voltage, resulting in severe MB damage 
Yes - and think of the effect of a good, hot fire on the rats-nest of
cables under the desk behind the NAS box. Who's to say that you wouldn't
get 240v on the CAT5 or a USB cable?
But, I wouldn't expect the motherboard to survive the file: it looks to
be outside the fireproofing wrapped round the disk, so with such a
design you can do all you need by putting a high voltage shunt across
the SATA leads as they enter the fireproof disk area.
OK, just heard back form Trevor Potts and the ioSafe guys.
I asked:
"When the PSU shorted out due to the fire, could it have fried the disks
by letting AC get into the NAS box or does it have designed-in features
that would prevent this happening?
As it looks, to me anyway, like a standard laptop power brick, this seems
like a reasonable question. I'll be very interested to hear what you
have to say about it.
"
And the reply from ioSafe is:
"In such an event, the worst case scenario is that any data in transit
would be lost. The data on the drives would not be lost.
"
....so it looks as though they've thought about this problem.
--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |