Selecting a DAT drive

[Jonathan Sachs]

My DDS-3 tape drive (a Sony SDT-9000) is malfunctioning, and I think
it's time for me to upgrade to DDS-4 or DDS-5. If you've had
experience with this technology, please comment: which brand(s) would
be most reliable?

After a couple of decades of extremely good experience with DAT
technology, my relationship with DDS-3 has been unhappy. My original
HP drive failed spontaneously after about three years of use, and its
replacement died after a couple of months. I then swore off HP and
bought the Sony, which lasted a couple of years before it started
eating tapes. Thus, my concern for choosing something I can count on.

 

[Arno Wagner]

My DDS-3 tape drive (a Sony SDT-9000) is malfunctioning, and I think
it's time for me to upgrade to DDS-4 or DDS-5. If you've had
experience with this technology, please comment: which brand(s) would
be most reliable?

After a couple of decades of extremely good experience with DAT
technology, my relationship with DDS-3 has been unhappy. My original
HP drive failed spontaneously after about three years of use, and its
replacement died after a couple of months. I then swore off HP and
bought the Sony, which lasted a couple of years before it started
eating tapes. Thus, my concern for choosing something I can count on.

Bets move away from DAT then. The revolving heads will allways cause
high wear and tear to the tapes and the themselves.

What media capacity are you looking for? How much capacity altogether?
Durability of indivicual media?

Arno

 

[Jonathan Sachs]

Best move away from DAT then. The revolving heads will allways cause
high wear and tear to the tapes and the themselves.

That was not my experience using DDS-2, DDS-1, and pre-DDS devices.
Are the more advanced versions of DDS less reliable? That seems
counterintuitive.

If I do abandon DAT, it's not clear to me what other options I have.
Before I bought the Sony drive I tried DLT technology, which was
supposed to be more reliable. I discovered the opposite. Maybe it is
reliable under data center conditions, but in a home with cats it
produced unrestorable backups several times a year.

Tape drives that use more advanced technologies appear to be very
expensive, as do the tapes. The price of admission would be $2k or
more, and I don't see how I can justify that for individual use.

What media capacity are you looking for?

My needs are somewhat elastic. At the moment I have no more than 13 GB
on any one drive, but any new client or personal project could change
that. My largest partition is 30 GB, but that is determined by the
estimated capacity of my backup media, rather than the other way
around. I do some audio restoration, which involves many 600 or 700 MB
WAV files , and I feel constrained by the number of projects I can
store on a DDS-3 tape. I think the best answer is that the more
capacity the media has the better an investment the drive will be --
provided it is reliable.

How much capacity altogether?

I don't understand the question. The whole point of backing up on tape
instead of a big disk is that total capacity can be increased
incrementally, without limit.

If it helps, I currently own about 3 dozen DDS-3 tapes, 18 of which
are in use.

Durability of indivicual media?

I typically write each backup tape between one and ten times, then
retain it for a year, during which I read it two or three times at
most. Then I reuse it. I expect these tapes to become obsolete before
they wear out, but I could live with limited media life if the media
were not too expensive.

For archival purposes I typically write once, read at most a few times
a year, and retain indefinitely.

 

[Rod Speed]

That was not my experience using DDS-2, DDS-1, and pre-DDS
devices. Are the more advanced versions of DDS less reliable?
That seems counterintuitive.

If I do abandon DAT, it's not clear to me what other options I have.

All tape formats are WAY past their useby date
now for the backup of personal desktop systems.

Before I bought the Sony drive I tried DLT technology, which was
supposed to be more reliable. I discovered the opposite. Maybe
it is reliable under data center conditions, but in a home with cats
it produced unrestorable backups several times a year.

Tape drives that use more advanced technologies appear to be very
expensive, as do the tapes. The price of admission would be $2k or
more, and I don't see how I can justify that for individual use.

Yep, you should be using hard drives, vastly cheaper.

My needs are somewhat elastic. At the moment I have no more
than 13 GB on any one drive, but any new client or personal
project could change that. My largest partition is 30 GB, but that
is determined by the estimated capacity of my backup media,
rather than the other way around. I do some audio restoration,
which involves many 600 or 700 MB WAV files , and I feel
constrained by the number of projects I can store on a DDS-3
tape. I think the best answer is that the more capacity the media
has the better an investment the drive will be -- provided it is reliable.

Yep, the only way to go is hard drives.

A couple of 120G+ eSATA hard drives is the only way to go.

I don't understand the question.

He means the total capacity of all the tapes involved in your media sets.

The whole point of backing up on tape instead of a big disk is
that total capacity can be increased incrementally, without limit.

Thats completely academic in your case, even a pair of 300G drives
gives you plenty of future and you can add another pair if you ever
run out of capacity, for a total cost of much less than DDSanything.

If it helps, I currently own about 3 dozen
DDS-3 tapes, 18 of which are in use.

Yeah, that's what he meant.

I typically write each backup tape between one and ten times,
then retain it for a year, during which I read it two or three times
at most. Then I reuse it. I expect these tapes to become
obsolete before they wear out, but I could live with limited
media life if the media were not too expensive.

No need for that farting around with non tapes.

 

[Jonathan Sachs]

I'm not going to respond to Rod's post, except to point out that he's
answering a question I didn't ask. I have plenty of reasons for using
tape which I'm not going to go into here (I have done so in the past,
if anyone cares to rummage through archives).

I requested information about the reliability of various brands of two
specific types of devices. To make this discussion useful, please,
let's limit the discussion to those topics.

 

[Rod Speed]

I'm not going to respond to Rod's post, except to
point out that he's answering a question I didn't ask.

The question you asked is the wrong question.

I have plenty of reasons for using tape

No you dont.

which I'm not going to go into here (I have done so in
the past, if anyone cares to rummage through archives).

They were duds then, and remain duds now.

I requested information about the reliability of various brands
of two specific types of devices. To make this discussion
useful, please, let's limit the discussion to those topics.

Taint gunna happen, because everyone with a clue has noticed that tapes
are WAY past their useby date for personal desktop systems now.

THATS why you cant buy what you want, the entire market has noticed.

 

[Michael L. Squires]

My experience with DLT drives, all surplus, has been much better than
my experience with DAT drives, some of the new.

I am currently using two ADIC VLS DLT 7000 changers (7 slots, 1 DLT 70000
35/70GB drive) which cost $150 each on eBay, plus a standalone Compaq DLT
7000. I haven't used these for long, having just switched over from an
ADIC VLS DLT 4000 changer and two stand-alone DLT 4000 drives which have
been 100%.

My expereince with ADIC VLS changers (several DLT 2000XT, several DLT 4000,
and now the two DLT 7000's) is that if they work on arrival, they seem
to work nearly forever.

I'm also using a 300GB Seagate IDE drive to store dumps, but I also need
to archive.

(We have two cats.)

Mike Squires
UNIX(tm) at home
since 1986

 

[Arno Wagner]

That was not my experience using DDS-2, DDS-1, and pre-DDS devices.
Are the more advanced versions of DDS less reliable? That seems
counterintuitive.

I have seen several of these wear out in about a year, with daily
backups.

If I do abandon DAT, it's not clear to me what other options I have.
Before I bought the Sony drive I tried DLT technology, which was
supposed to be more reliable. I discovered the opposite. Maybe it is
reliable under data center conditions, but in a home with cats it
produced unrestorable backups several times a year.
Hmm.

Tape drives that use more advanced technologies appear to be very
expensive, as do the tapes. The price of admission would be $2k or
more, and I don't see how I can justify that for individual use.

My needs are somewhat elastic. At the moment I have no more than 13 GB
on any one drive, but any new client or personal project could change
that. My largest partition is 30 GB, but that is determined by the
estimated capacity of my backup media, rather than the other way
around. I do some audio restoration, which involves many 600 or 700 MB
WAV files , and I feel constrained by the number of projects I can
store on a DDS-3 tape. I think the best answer is that the more
capacity the media has the better an investment the drive will be --
provided it is reliable.

MOD is out then. That is what I use.

I don't understand the question. The whole point of backing up on tape
instead of a big disk is that total capacity can be increased
incrementally, without limit.

If it helps, I currently own about 3 dozen DDS-3 tapes, 18 of which
are in use.

It is an economic question. If you need lots of space you can invest
more in the drive if the media are cheaper as a consequence.

I typically write each backup tape between one and ten times, then
retain it for a year, during which I read it two or three times at
most. Then I reuse it. I expect these tapes to become obsolete before
they wear out, but I could live with limited media life if the media
were not too expensive.

For archival purposes I typically write once, read at most a few times
a year, and retain indefinitely.

I think this is a case for professional tape. Maybe LTO?
AIT is heli-scan as well, with the associated complex and
problematic mechanics...

Arno

 

[Jonathan Sachs]

My experience with DLT drives, all surplus, has been much better than
my experience with DAT drives, some of the new....

(We have two cats.)

That's potentially valuable information, but unfortunately it's not
clear whether the particular drives you mentioned are cat-proof, or
some other factor is at work. I'm reluctant to make an assumption
about that -- or make myself a guinea pig for testing one -- when my
data is at stake.

When I made my sally into DLT I bought two HP SureStore DLT40 drives
so that I'd have a spare if one broke. I had the same problem with
both of them, so I can't blame the problem on a bad drive.

 

[Jonathan Sachs]

I think this is a case for professional tape. Maybe LTO?
AIT is heli-scan as well, with the associated complex and
problematic mechanics...

That's an interesting possibility. I assumed LTO was too far out of my
price range to warrant attention, but I look and found that LTO-1
drives are about as expensive as DDS-5 drives, and the tapes are
available for less than $10 each.

I've got a business trip coming up, and I don't have time to research
a new technology now. I think I'm going to buy a removable disk drive
so that I'll have SOME backup, then research this when I have more
time.

Any other pointers or hints you can give me about LTO technology and
brands will be appreciated!

 

[Charles C.]

That's potentially valuable information, but unfortunately it's not
clear whether the particular drives you mentioned are cat-proof, or
some other factor is at work. I'm reluctant to make an assumption
about that -- or make myself a guinea pig for testing one -- when my
data is at stake.

DAT is not reliable ... I have a collection of DAT1, and 2 drives that
did not last 3 years on what I would consider not to be heavy use.
Apparently (contact me off list if you want some more details) dust in
the environment gets baked on the head(s ?) and that is that. The
advantage of DAT was price of the media ...

I am not sure I would trust the media for archival purposes either.

When I made my sally into DLT I bought two HP SureStore DLT40 drives
so that I'd have a spare if one broke. I had the same problem with
both of them, so I can't blame the problem on a bad drive.

As an afterthought, which is what I am doing after my external Sony DAT4
8 tape autoloader broke 2 weeks before the end of 3 warranty, get an
external DAT drive and turn it on to back up and off again as soon as
the back up is over. Keep it clean ... cover for dust or whatever (I am
not doing that). Cats are not - I think - the problem, there is much
finer dust around from clothes, carpets, human skin etc.

Look for something else if you can afford it.

Regards
Charles

 

[map]

If I do abandon DAT, it's not clear to me what other options I have.
Before I bought the Sony drive I tried DLT technology, which was
supposed to be more reliable. I discovered the opposite. Maybe it is
reliable under data center conditions, but in a home with cats it
produced unrestorable backups several times a year.

If you haven't already you should research the Exabyte VXA.

Their packet technology is unique and should be more rugged than others,
especially in a non controlled environment.

Price and capacity should also be in your range

 

[Mike Tomlinson]

That was not my experience using DDS-2, DDS-1, and pre-DDS devices.

Mine neither. Except Exabyte 8200 and 8500 drives - spawn of Satan...

Are the more advanced versions of DDS less reliable?

They do seem to be more fragile, probably a combination of refining the
technology to pack more data into the same form factor, coupled with the
need to build down to a price.

 

[Mike Tomlinson]

If I do abandon DAT, it's not clear to me what other options I have.
Before I bought the Sony drive I tried DLT technology, which was
supposed to be more reliable.

It is, without question.

I discovered the opposite. Maybe it is
reliable under data center conditions, but in a home with cats it
produced unrestorable backups several times a year.

I think you were probably unlucky. I use four Compaq DLT7000s daily in
a typical office (overheated, dusty, but no office cat), have done for
several years, and the only problem I have had is with Sony-branded
tapes, which the drives did not like at all. They're fine with Fujifilm
DLT IV tapes and about a dozen DLT IIIXT tapes I still use.

I've had two drive failures. One was a DLT2000 drive which gave up the
ghost after nine years of daily use, so it didn't owe us anything, and
the other was a DEC TZ89 (= DLT7000) drive which started acting up after
one of the aforementioned Sony tapes - brand new, just opened - was put
in it. It was never the same again, so I replaced it and returned the
rest of the Sony tapes I'd bought, unopened, for exchange with Fuji
media which has been problem-free.

 

[Mike Tomlinson]

AIT is heli-scan as well, with the associated complex and
problematic mechanics...

AIT's been ok for me (5 drives in daily use.) I think the high quality
of construction of the drives and tapes is an important factor.

 

[Mike Tomlinson]

Any other pointers or hints you can give me about LTO technology and
brands will be appreciated!

I've been using an LTO-3 drive on evaluation for about a year and have
been happy enough to invest in a 10-slot LTO-3 rack-mounted jukebox (8Tb
total capacity.)

 

[Arno Wagner]

AIT's been ok for me (5 drives in daily use.) I think the high quality
of construction of the drives and tapes is an important factor.

Good data point. DAT may just have come too much out of the
consumer corner. (Even high-end audio is consumer gade stuff,
don't be fooled by spacy design and gold plating.)

LTO, AIT, DLT all do not have that legacy.

Arno

 

[Folkert Rienstra]

Good data point.

As in: the bot has been found babbling again, as always.

DAT may just have come too much out of the
consumer corner.

(Even high-end audio is consumer gade stuff,
don't be fooled by spacy design and gold plating.)

Whatever that has to do with topic.

LTO, AIT, DLT all do not have that legacy.

As in tape was never a consumer article. Stupid bot, as always.

 

[Jonathan Sachs]

IBM and HP appear to be the most popular brands, and I've also seen
drives from Dell, Seagate, and Quantum offered for sale.

Any comments on whether one brand of drive is likely to be more/less
reliable than others?

Any comments on brands of tape?

 

[Jonathan Sachs]

I posted an earlier version of this message but neglected to mention
the context, so it would have been confusing to anyone who didn't see
the preceding message. My apologies for that.

IBM and HP appear to be the most popular brands of LTO drives, and
I've also seen drives from Dell, Seagate, and Quantum offered for
sale.

Any comments on whether one brand of drive is likely to be more/less
reliable than others? (I'm specifically interested in LTO-1.)

Any comments on brands of LTO tape?