[Info-vax] Media failures, was: Re: grey screen of death

[Simon Clubley]

On 2015-05-24, Stephen Hoffman <seaohveh at hoffmanlabs.invalid> wrote:
> On 2015-05-24 16:30:46 +0000, Simon Clubley said:
>
>> I meant what I said about bitrot BTW; I've just retired a HP USB stick 
>> which had started flipping the bits in some files which had been 
>> unchanged on the USB stick for a while; the verify pass caught it after 
>> some unrelated files were added to the same backup partition on the USB 
>> stick.
>
> Um, so?   CD and DVD media also degrades, too.  Sometimes badly.   I've 
> had mis-recorded DVD disks arrive locally, and have had verified media 
> fail in short order.   Batches of bad media from well-known vendors 
> have occurred, too.   Some of the 9-track tape media shed the recording 
> substrate all over the spools and all over the tape drive heads.   
> You've undoubtedly experienced other problems and other failures with 
> other media, as have other folks.
>

It's about failure rates Hoff. I can't remember a DEC/CPQ/HP supplied
CD/DVD failing on me but I have seen multiple flash drive failures,
including branded ones. That's why I would prefer DVDs instead of flash
drives for any future software distribution.

As for 9 track tape, let's just say I'm glad it's a part of ancient
history. :-)

As for locally burnt DVD media, the majority of failures occur during
burning so you know about it right away. I have had DVDs go bad some
time after burning, but off the top of my head, I can't put a figure
on the frequency. I do perceive locally burnt DVD media as more reliable
than flash drives however.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world