Keith C. Perry on 13 Apr 2016 10:35:50 -0700

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Re: [PLUG] Desktop Support ?

Things aren't quite that clean- once electrical systems go out of spec (e.g. under or overvoltage how that is caused... e.g. source, parasitic, cascading events creates a dynamic failure) all bets are off since it is impossible to detect and trap multi-system faults unless you have external supervisory circuitry in place.

Even on a journaling FS, garbage in = garbage out

Ibid for RAID...

Those mechanisms address availability not data protection.  This is why backing up your data and system is so important.

That said, on journaling FS' you would probably be able to at least mount the system (which it sounds like you did) and then pull off anything important, if not corrupt.  I would not trust a file system after an event like that- bad things seem to always happen again- later... when you least expect it.

I would continue to watch the hardware too.  There certain electrical components that fail in a more mechanical way so at some point in the future weird things may happen that appear random.  I tend to make note of all substantial failures in case an need to dig through history for pattern analysis.

You have the right idea.  Reinstalling and restoring you data is your best move so you have confidence in you system.


On Apr 13, 2016 12:23 PM, "Rich Mingin (PLUG)" <> wrote:
I wouldn't think gibberish was written to the drive due to low voltage. Generally you're either getting the volts you need from the DC-to-DC converter or you aren't.

On the other hand, when that voltage suddenly cuts off because the battery has gotten too low to go on? You stop where you are, you aren't allowed to wrap up any writes that are in progress. A partially-completed write is supposed to be handled by the journaling filesystem, but nothing is flawless, and errors can happen.

Depending on how old that eepc Ubuntu install is, it might even be a non-journalling FS, which would certainly eat it on sudden power cut.

On Wed, Apr 13, 2016 at 12:09 PM, Greg Helledy <> wrote:
On the netbook, it sounds to me like something on the HD became corrupted when the machine ran out of power.  As the voltage from the battery was dropping lower and lower, it may have begun writing gibberish to the drive...this might have gone on a while before the machine quit altogether.  The good news is it's unlikely that the hardware itself is damaged, but the bad news is that it's very possible that more than the one file the computer complains about is corrupted.

I don't know how to go about recovering from something like that, others may have advice there.  In the worst case, copying your personal files onto something else and doing a format and reinstall should fix it.

Greg Helledy
GRA, Incorporated
P:  +1 215-884-7500
F:  +1 215-884-1385

On 4/13/2016 8:31 AM, wrote:
Re: [PLUG] Desktop Support ?
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