DLT or LTO or AIT for new tape drive?

  • Thread starter Thread starter Lady Margaret Thatcher
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Lady Margaret Thatcher

I have a home LAN with about 20 GB online. As I get more into digital
photography and possibly even videos, I expect that amount of storage
can grow quite a lot in the next few years.

My current tape drive is 7/14 GB, and a full backup each month
requires about 4-5 media changes, counting the verify cycle. I would
like to get a drive that allows me to fit say 40 GB (or more) onto one
cartridge. Without bankrupting my Treasury of course.

Should I focus on DLT or AIT or LTO? 68-pin SCSI or even SCA.

Which format is most reliable and cost-effective, considering both
drive and media cost? What about buying a drive used on eBay? (no
flames please!) Are any of these formats dead-ends like my current 8
mm drive/format?

I don't need to back up 20 GB in say 30 minutes. I doubt my systems
could even pump out the data fast enough. (I'm moving to 1 GB LAN for
my newer systems.) A drive with say 40-80 GB native storage would
give me enough "headroom" so that even 2-4 years from now, I should
still be able to do a full backup with one cartridge.

Also, do any of these formats "shoeshine" the tape if the drive isn't
getting data fast enough?
 
Lady Margaret Thatcher said:
I have a home LAN with about 20 GB online. As I get more into digital
photography and possibly even videos, I expect that amount of storage
can grow quite a lot in the next few years.

My current tape drive is 7/14 GB, and a full backup each month
requires about 4-5 media changes, counting the verify cycle. I would
like to get a drive that allows me to fit say 40 GB (or more) onto one
cartridge. Without bankrupting my Treasury of course.

Should I focus on DLT or AIT or LTO? 68-pin SCSI or even SCA.

Which format is most reliable and cost-effective, considering both
drive and media cost? What about buying a drive used on eBay? (no
flames please!) Are any of these formats dead-ends like my current 8
mm drive/format?
Click to expand...

How about VXA-2 from Exabyte? Cheap drives, very reliable technology. By
using the short X6 tapes you can get the capacity you need today at a very
good price, and if you need more capacity you can go to X10 or X23 tapes for
more.

All media formats are dead-end at some point. DDS is dead-end today.Your
current 8mm drive format has been around for 25 years before becoming
obsolete. DLT is about to become extinct. LTO is master of the enterprise
universe today, but real overkill for your application.

Rob
 
Lady Margaret Thatcher said:
I have a home LAN with about 20 GB online. As I get more
into digital photography and possibly even videos, I expect that
amount of storage can grow quite a lot in the next few years.
Click to expand...

Tape is well past its useby date for that situation now.
My current tape drive is 7/14 GB, and a full backup each month
requires about 4-5 media changes, counting the verify cycle. I
would like to get a drive that allows me to fit say 40 GB (or more)
onto one cartridge. Without bankrupting my Treasury of course.
Click to expand...

Makes a lot more sense to use and extra hard drive for that situation,
with new photos written to duplicated DVD media to protect against
theft of the system, fire and flood etc, one copy offsite.
Should I focus on DLT or AIT or LTO? 68-pin SCSI or even SCA.
Click to expand...

None of the above.
Which format is most reliable and cost-effective, considering both
drive and media cost? What about buying a drive used on eBay?
(no flames please!) Are any of these formats dead-ends like my
current 8 mm drive/format?
Click to expand...

Yep, all of them basically in your situation.
I don't need to back up 20 GB in say 30 minutes. I doubt my systems
could even pump out the data fast enough. (I'm moving to 1 GB LAN for
my newer systems.) A drive with say 40-80 GB native storage would
give me enough "headroom" so that even 2-4 years from now, I should
still be able to do a full backup with one cartridge.
Click to expand...

So another hard drive makes a lot more sense.
 
Lady said:
I have a home LAN with about 20 GB online. I would
like to get a drive that allows me to fit say 40 GB (or more) onto one
cartridge. Without bankrupting my Treasury of course.

Should I focus on DLT or AIT or LTO? 68-pin SCSI or even SCA.
Click to expand...

No I would go with VXA from Exabyte
 
How about VXA-2 from Exabyte? Cheap drives, very reliable technology. By
Click to expand...

Well, nothing against Exabyte, but their drives and media, while good,
aren't as bullet-proof, never-fail as my earlier QIC drives, including
a 1 GB native Tandberg drive. But that format seemed to becoming
obsolete, and newer drives couldn't even read some of the older QIC
formats.

I would like to avoid that scenario again.

using the short X6 tapes you can get the capacity you need today at a very
good price, and if you need more capacity you can go to X10 or X23 tapes for
more.
Click to expand...

Sounds good. I'll have to check it out. Which vendor is preferred?
Or to be avoided.

All media formats are dead-end at some point. DDS is dead-end today.Your
current 8mm drive format has been around for 25 years before becoming
obsolete. DLT is about to become extinct. LTO is master of the enterprise
Click to expand...

Ah. I hadn't realized that DLT is dead-ending. LTO might be nice.
If it is master of the enterprise, that tells me it's reliable. But
it also tells me that it could be too expensive for me, and the native
transfer rates to keep an LTO drive "full" might be more than my LAN
could possibly supply.

I previous asked about "shoeshining" with different formats. Is AIT
less prone to shoeshining than the other formats?

universe today, but real overkill for your application.
Click to expand...

Yes, could be. Heck none of my systems are even rack-mounted, and
every self-respecting enterprise I know about is all "how many U is
that server, " and about blade servers to increase CPU density per
rack.

Thanks for your reply.

Thatcher
 
No I would go with VXA from Exabyte
Click to expand...

OK. You seem to agree with the other person who replied. Why?

Which vendors/models would you like?

Thatcher (Desdemona)
 
Lady Margaret Thatcher said:
OK. You seem to agree with the other person who replied. Why?

Which vendors/models would you like?
Click to expand...

VXA is just very robust technology for an attractive price, I guess Iago
found that out too ;-) Full disclosure: I'm a bit brainwashed myself, I've
worked for Exabyte for many years.

There's just one vendor for VXA, it's Exabyte. The media is manufactured by
three or four different companies, but you can't order any specific brand.
They all sell through Exabyte/Imation, they all work equally well.

I like the SCSI version internal version, but you have a choise of IDE, SCSI
and Firewire. The Firewire is nice if you want to move the drive from one
system to the next. The IDE drives are meant for OEM's, not sure if you can
get them through normal channel shops. You can always call Exabyte and find
out.

VXA-3 is due out soon. This will give you double capacity and speed on the
same tapes. The drives may be a bit higher priced, but if nothing else it
will make VXA-2 go down in price..

Rob
 
VXA is just very robust technology for an attractive price, I guess Iago
found that out too ;-) Full disclosure: I'm a bit brainwashed myself, I've
worked for Exabyte for many years.
Click to expand...

Well, I just popped over to the Exa site and yes, VXA does seem to be
the right option for me. Glad people replied with "other."

One question, if you don't mind. About 12-15 months ago, I had some
dealings with Exa support. One of the support people there, who were
all very helpful, told me that the company was not doing well and
layoffs were impending. How is business these days? Is headcount
stable or growing?
There's just one vendor for VXA, it's Exabyte. The media is manufactured by
three or four different companies, but you can't order any specific brand.
They all sell through Exabyte/Imation, they all work equally well.

I like the SCSI version internal version, but you have a choise of IDE, SCSI
Click to expand...

I've been a SCSI guy since it was spelled SASI. :) Worked at the
(long-gone) company where SASI was invented and commercialized.
and Firewire. The Firewire is nice if you want to move the drive from one
system to the next. The IDE drives are meant for OEM's, not sure if you can
get them through normal channel shops. You can always call Exabyte and find
out.

VXA-3 is due out soon. This will give you double capacity and speed on the
same tapes. The drives may be a bit higher priced, but if nothing else it
will make VXA-2 go down in price..
Click to expand...

Yeah, and I'm not sure that I really need VXA-3. And yes, I'm hoping
that people will upgrade, so these older drives will suddenly flood
ebay, driving down those prices also.

What is your opinion of buying a VXA drive used off ebay?
 
Did you consider backing up to external USB disk?

It is certainly faster to backup and restore, cheaper, verifiable, and
eventually more reliable.

The fact that backup to disk is here to stay is a fact. There are
solutions such as the Relative Rev Backup that treats backup to disk in
a completely new way, making it robust and cost effective at the same
time.



Joe Rom King
 
Did you consider backing up to external USB disk?

It is certainly faster to backup and restore, cheaper, verifiable, and
eventually more reliable.

The fact that backup to disk is here to stay is a fact. There are
solutions such as the Relative Rev Backup that treats backup to disk in
a completely new way, making it robust and cost effective at the same
time.
Click to expand...

Downside of using hard disks for backup:

1. As fragile as (or even more fragile than) the primary device on which
the data is stored. Likely to die if handled without extreme care. (I
lost an external drive and all its data when somebody bumped it while it
was spinning.) The data in your machine is on SCSI drives because you
care about "industrial-strength" solutions*, but you're willing to
entrust your backups to a USB-connected device that contains an "it's
good enough for home users" IDE drive?

2. How many "generations" of backups can/will you store on one?

3. How many redundant copies can/will you store off site?

*I am reading this on the SCSI ng.

Perce
 
Did you consider backing up to external USB disk?
Downside of using hard disks for backup:

1. As fragile as (or even more fragile than) the primary device on which
the data is stored. Likely to die if handled without extreme care. (I
lost an external drive and all its data when somebody bumped it while it
was spinning.) The data in your machine is on SCSI drives because you
care about "industrial-strength" solutions*, but you're willing to
entrust your backups to a USB-connected device that contains an "it's
good enough for home users" IDE drive?

2. How many "generations" of backups can/will you store on one?

3. How many redundant copies can/will you store off site?

*I am reading this on the SCSI ng.
Click to expand...

Did you notice OP said: "I have a home LAN with about 20 GB online."? He
didn't say that he uses SCSI drive for data. "Industrial-strength" solution
is nice, but not everybody can afford it.
 
Lady said:
OK. You seem to agree with the other person who replied. Why?

Which vendors/models would you like?

Thatcher (Desdemona)
Click to expand...
Well you got most answers if not all from Rob Turk. I haven't worked
for Exabyte,(nor do I work for them now in any capacity) but they make
some good stuff. I like their Magnum autoloader, to name one.

Back to VXA, it's probably one of the most interesting tape
technologies around, I am sure you'll find out everything (from their
Web site) on packet recording and its low cost/high reliabilty ratio.

VXA and AIT tapes both fill that gab between the low end and the top
of the line. VXA is perhaps less expensive but doesn't have the Sony
name behind.

I can't speak about Exabyte future, you'll have to talk to a fortune
teller for that.
 
Perce

Tape has its own vulnerabilities:

Humidity will ruin any tape. Placing the tape near an electromagnet
source such as generator or a big electric engine are great ways to
implement a "secure delete". Placing the tape is a closed car in
the summer time, is another dead end road for tapes. Tapes are
vulnerable to wear and tear, about 30-50 cycles before they die on you.

I know a customer that lost all of his data because his tape drive was
near a copy machine causing the toner particles in the air to make all
of his tapes unreadable.

Try shuttling a tape drive while it writes to tapes, especially if you
tilt them in a way that causes radial forces, and the tape will be
KPUT.

Statistics shows that 40%-60% of tape restores fails. Validating the
backed up data on tapes are very hard, sentencing your organization to
a life at the foothill of an active volcano.

Disk is vulnerable to sever drop (can be easily solved with a cushioned
transport packaging), but is mostly immune to all above mentioned items
because of the hermetically sealed environment it operates in (dirt and
electromagnetic wise).

The logical conclusion is not to rely on a single backup media, be it
tape or disk.

Now for your question regarding generations and number of media:
Relative Rev Backup has a unique management algorithm that makes sure
you can have many months worth of backup generations stored on each
backup disk. However, if you have at least two backup disks in daily
rotation, any damage to any disk will result in loosing the backup of
the last day only. (Same effect as damaging the last tape).

That is what I mean by robust and cost effective at the same time.


Joe Rom King
 
Joe said:
Perce

Tape has its own vulnerabilities:

Humidity will ruin any tape. Placing the tape near an electromagnet
source such as generator or a big electric engine are great ways to
implement a "secure delete". Placing the tape is a closed car in
the summer time, is another dead end road for tapes. Tapes are
vulnerable to wear and tear, about 30-50 cycles before they die on you.

I know a customer that lost all of his data because his tape drive was
near a copy machine causing the toner particles in the air to make all
of his tapes unreadable.

Try shuttling a tape drive while it writes to tapes, especially if you
tilt them in a way that causes radial forces, and the tape will be
KPUT.

Statistics shows that 40%-60% of tape restores fails. Validating the
backed up data on tapes are very hard, sentencing your organization to
a life at the foothill of an active volcano.

Disk is vulnerable to sever drop (can be easily solved with a cushioned
transport packaging), but is mostly immune to all above mentioned items
because of the hermetically sealed environment it operates in (dirt and
electromagnetic wise).

The logical conclusion is not to rely on a single backup media, be it
tape or disk.

Now for your question regarding generations and number of media:
Relative Rev Backup has a unique management algorithm that makes sure
you can have many months worth of backup generations stored on each
backup disk. However, if you have at least two backup disks in daily
rotation, any damage to any disk will result in loosing the backup of
the last day only. (Same effect as damaging the last tape).

That is what I mean by robust and cost effective at the same time.
Click to expand...
On the other hand...
Why are backups done to a cycle of tapes?
Sometimes you need to restore a tape from 3 days ago, a month ago or
even from the previous year. Sometimes companies get pestered by
auditors.

They would laugh (in an evil way) if you revealed that you put your
trust in IDE disks which you had transported off-site daily.

A NAS system (separate site) might just about be acceptable.
But a tape system would be better - tapes are designed to be
transported.
 
Joe said:
Tapes are
vulnerable to wear and tear, about 30-50 cycles before they die on you.
Click to expand...

Nonsense. DLT and AIT tapes are rated for many more passes than that
(and I've done many thousands of backups on the same DLT tapes. The
drive still shows no errors reading or writing those tapes.)
 
Joe Rom King said:
Perce

Tape has its own vulnerabilities:

Humidity will ruin any tape. Placing the tape near an electromagnet
source such as generator or a big electric engine are great ways to
implement a "secure delete". Placing the tape is a closed car in
the summer time, is another dead end road for tapes. Tapes are
vulnerable to wear and tear, about 30-50 cycles before they die on you.
Click to expand...

This is a prime example of FUD. I dare you to erase any modern tape with
anything 'big electric' these days. Today's tapes have such a high
coercivity that even a standard bulk eraser will not be able to generate
enough of a magnetic field to erase a modern high density tape.

Your tape cycles are off by a factor of at least 10 also. There's no problem
using tapes hundreds of times. I have encountered tapes that were used over
5000 times (and that means at least 30.000 passes on such a tape) which were
perfectly readable.

High temperature might be an issue, and leaving tapes in a hot closed car
out in the sun isn't good. But since anyone knows that, it's the owner's own
stupidity if (s)he chooses to do so. But that would also apply to any
laptop, your dog, your kids, you name it..

FUD it is...

Rob
 
Lady Margaret Thatcher said:
Well, I just popped over to the Exa site and yes, VXA does seem to be
the right option for me. Glad people replied with "other."

One question, if you don't mind. About 12-15 months ago, I had some
dealings with Exa support. One of the support people there, who were
all very helpful, told me that the company was not doing well and
layoffs were impending. How is business these days? Is headcount
stable or growing?
Click to expand...

Headcount is stable right now. There were some layoffs about a year ago when
Exabyte was in the middle of transitioning from high-value Mammoth drives
and libraries to commodity VXA drives and automation. I know first hand as I
was one of the 'victims' of the transition. I hold no grudge to the company
at large, and in fact I still do work for them every now and then. All
non-Windows software tools on their website (DOS, Netware, Linux, Solaris
etc... ) are still being maintained by me on a freelance base.
Yeah, and I'm not sure that I really need VXA-3. And yes, I'm hoping
that people will upgrade, so these older drives will suddenly flood
ebay, driving down those prices also.

What is your opinion of buying a VXA drive used off ebay?
Click to expand...

I see no problem buying a used VXA drive from a reputable seller. Most
available drives are VXA-1 drives from folkes who were happy with it and
went to VXA-2. I'm sure VXA-2 drives will show up more frequent when VXA-3
is out. As with all used equipment you'll want to be able to test and return
it to the seller if there's an issue with it.

Rob
 
In comp.sys.ibm.pc.hardware.storage Joe Rom King said:
Perce
Click to expand...
Tape has its own vulnerabilities:
Click to expand...
Humidity will ruin any tape. Placing the tape near an electromagnet
source such as generator or a big electric engine are great ways to
implement a "secure delete". Placing the tape is a closed car in
the summer time, is another dead end road for tapes. Tapes are
vulnerable to wear and tear, about 30-50 cycles before they die on you.
Click to expand...
I know a customer that lost all of his data because his tape drive was
near a copy machine causing the toner particles in the air to make all
of his tapes unreadable.
Click to expand...
Try shuttling a tape drive while it writes to tapes, especially if you
tilt them in a way that causes radial forces, and the tape will be
KPUT.
Click to expand...
Statistics shows that 40%-60% of tape restores fails. Validating the
backed up data on tapes are very hard, sentencing your organization to
a life at the foothill of an active volcano.
Click to expand...
Disk is vulnerable to sever drop (can be easily solved with a cushioned
transport packaging), but is mostly immune to all above mentioned items
because of the hermetically sealed environment it operates in (dirt and
electromagnetic wise).
Click to expand...

You seem to be unaware that there is a whole range of tape solutions
out there, from unreliable as you claime to very reliable. I personally
pulled several TBs of measurement data from professional tape recently,
without any reading errors at all.

Also the claim that "validating backed up data on tapes is very hard"
is completely bogus. You can do the same you do with any storage
medium: Read it. Also professional tape solutions usually have vastly
superiour error correction and spreading out of the data so that
even data from a torn tape can often be completely recoverd. Of course
if you handle your tape in an amateurish fashion, you can kill it.

But maybe getting somebody that know their stuff to do the backup
is a better option anyways than to follow your advice and have
incompetence as the major risk.

Arno


P.S.: It is "kaput" (german) from french "capot". Not too impressive
spelling it wrong and in capitals.
 
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