No. But I did encounter a lot of dead HDDs.
So? A dead disk doesn't damage anything else. A scratched head destroys
every tape you stick in the drive, and if whatever scratched it comes off
on one of them then that tape destroys every drive you put it in.
My point is that tape drive failures can and do affect the media. And then
there are the freaking travans, whose media sometimes is readable in only
the one drive in which it was written.
What I meant to say, if a HDD fails, in most cases you've lost every
single bit. Normally, you can't take out magnetic disks and put them
into another HDD, can you? On the other hand, if there's a CRC error
on a piece of tape, you usually lose a file, not the whole tape.
That may be the case for uncompressed data. If you're using compression
then it's a different story.
If you lose "every single bit" on yesterday's backup, so what? That's why
you do rotation backups.
No, it does not. Have you ever studied engineering somewhere? A tape
casette consists of tape, rollers and a case. A HDD has millions of
components, including silicon gates inside microchips, motors, heads,
positioning mechanism and so on.
Actually I have studied engineering, but I've also actually done it in the
real world, which you clearly haven't if you think that complexity is the
only factor in reliability. Some types of tape cartridge, DLT for example,
are very reliable. Other types (DDS for example) are documented by the
manufacturer to have limited service lives. Most of your "millions of
components" are gates in a chip, and modern silicon is vastly more reliable
than any mechanical device. As for parts count, a modern disk typically
has two moving parts, the head assembly and the platter assembly, and no
contact between the heads and the magnetic media during normal operation,
unlike tape that wears both the heads and the media constantly.
No disk that I know of needs regular maintenance in order to remain usable.
Most types of tape have a required cleaning cycle--if you get sloppy with
it the drive goes and often takes some of your tapes with it.
Reliability is not as simple as you make it out to be.
Did I suggest using the same media for a week? I think I did not. So
you imagined something and called that stupid. Very smart of you!
Then what does "a tape per week" mean? Say what you mean, don't expect
people to read your mind.
Yes, I do criticize a backup strategy that is flawed regardless of the
type of media used. What's the problem? Unless you are that terminally
stupid to praise such a strategy...
The problem is that you are claiming that disks are not satisfactory backup
devices because if that flawed strategy is used an unacceptable amount of
data loss will occur, when in fact if that same strategy is used then the
same occurs with tape.
Apparently you are much smarter than Sony, IBM etc that produce tape
drives, let alone those people who buy them.
I'm certainly smarter than the people who buy Sony tape drives
ACK.
GAHH. (making signs to ward off evil spirits).
But most of the businesses that buy those drives don't need to "keep years
of backup in different places". They may keep archives of various kinds
(last I heard Lucasfilm used DLT to archive their CGI for example) but
archives are not backups. There is a tendency to confuse the two. Backup
is what you use to minimize data loss in the event of a catastrophic
failure. If you have to go to a years-old backup then you may as well not
have bothered in most cases.
On the other hand you may need to pull something out of a years-old archive.
And if you are archiving anything valuable I would hope you had made at
least two copies on two different types of media and stored them in
different places.
I don't mind backing up
to HDDs. I do personally back up to HDDs, as well as tapes, CD, DVDs
and flash.
Excuse me, but the choice is not "always use disk and never use tape" and it
is not "always use tape and never use disk". The choice is to run a cost
analysis and use whatever type of backup is most cost-effective for the
given circumstances. You seem to be trying to make up circumstances under
which disk is not optimal and then claim on that basis that disk is always
an unacceptable form of backup. If that's not your intent you need to
learn to write more clearly.
