[TenTec] OT: Old QSTs, CQs, etc.

Rick - DJ0IP / NJ0IP Rick at DJ0IP.de
Sat Dec 31 01:05:02 PST 2011


Ah... yes...   But, I, also, have a finite life and from
		   what I read I will be gone, or lose my memory, 
               long before my CDs lose their memory.     

James,  WRONG, DANGEROUSLY WRONG!

CD and DVD medial are similar to disk drives when it comes to failing.
MOST of them may outlive you, but that does NOT mean ALL of them will.
The failure rate is quite low (I don't have the latest spec in my head for
magnetic optical), but enough of them do fail that you should be concerned
and if you value your data, take this very serious.  (Less important for
archived multi-medial data).

With disk drives, I can quote the spec since I worked for the world's
largest disk drive manufacturer until I retired 8 months ago.  With an
annualized failure rate of 99.7%, you have a huge chance that if you buy a
new disk drive, your data will be safe on it for 5 years (the design EOL of
the drives).  That does not mean that the drives won't live longer; it just
means "how and when they die" after that time period is not factored in to
the AFR spec.

Most of us feel comfortable with new drives; we "think" our data is safe.
Well I've spent an awful lot of time trying to help some of the 0.3% of the
customers who lost data on relatively new drives and were foolish enough
(interpret that to be stupid enough) to think they did not need a backup
copy of their important data.

It's no different with CDs or DVDs.
The thing about it is, since this media is usually used for archive copies
of data which most people will never access again in their lives, most
people who have lost data never even realize that they have lost it because
they never had the need to attempt to access the particular file which was
lost.  

When I say "lose data", I don't mean the entire CD or DVD will fail.  What
we're talking about here is called "drop out" - where a few bad spots on the
media cause the data, perhaps just a few bits, to deteriorate to the point
that it can no longer be read.  Usually it's just a block or two that
failed, but that particular file is gone.  And Murphy will probably make
sure it was a block in the middle of the most important file (the one that
confirms you don't owe your ex-XYL any money) that will fail!

Here is something to think about:

QUESTION:  With the reliability of disk drives (and DVDs) being so good
today, do I still need to back up all of my data.

ANSWER:  NO!  (you only need to back up the data which you wish to keep)
(-:

I intentionally put a smiley face in there because I receive a retirement
pension from a storage company!

AND MY FINAL POINT IS:  
There is a HUGE difference between losing data in a multi-media file (music
or video), and losing data in a data file. If you lose data in a video, you
probably will just have a lost frame, which the eye will not even see; worst
case the screen flickers once or twice.  But if the lost block of data is in
the middle of your archived copy of your tax returns for 2008, and the IRS
decides to audit your last 5 years, you're hosed.  

73
Rick, DJ0IP

-----Original Message-----
From: tentec-bounces at contesting.com [mailto:tentec-bounces at contesting.com]
On Behalf Of Richards

My wife claims I have lost my mind already !
(no smiley face... because it is TRUE !)

--> I sure can't argue that point, James!  (-;





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