Summary: DLT experiences

From: Brian James O'Connor <boc_at_ironbark.bendigo.latrobe.edu.au>
Date: Mon, 16 Dec 1996 10:23:14 +1100 (EST)

Hello,
      my question was;
-----------------------------------------------------------------------
Hi,
   we are considering moving to a DLT drive to backup a rapidly
growing raid array on a AS 2100(4/200).
Currently its at 12GB, but once we bring the other two ports in to
use that will probably grow to:

swxcr 230 raid array(three port pci)
7x2GB 12GB(current)
7x4GB 24GB
7x4GB 24GB
     -----
      60GB at least

currently I'm switching tapes all day with a tlz06 dat drive!

Are the DEC DLT drives as good as the Quantum DLT drives?

What are your experiences with using Quantum DLTs with a Alphaserver?
and apart from the usual UNIX tools(dump,tar) what is the best s/w to
use with the DLT's , this must include the capablity for restoring
from a total system crash.(ie if the root partition is fried do I have to
restore with dump, and am I stuck with having to use the tlzo6 to do this)

What about libraries?

Whew what a grab bag of questions, in general I guess, what do people think
of DLT as the primary backup solution?

-----------------------------------------------------------------------

I got alot of postive responses although, David Walters has found the Quantum
hardware to be unreliable, and the service slow.

It looks lok DLT is the way to go. Note that I have included a previous summary
on dlt from Karl E. Liliestedt since our questions were similar.

The response from alan_at_nabeth.cxo.dec.com was particularly usefull.

Thanbks to all who replied

The responces;

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


>From barnwell_at_jbsvax.eksystems.com Tue Dec 10 08:00:10 1996

as far as I know they are the same drives as dec sold its storage (disk/tape)
business to Quantum about 2 or so years ago.

I have a tz87 on a 2100-4/275 and one on a vax4000 they hold a lot (20Gb) and
they go fast.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From sanghvi_at_proto.wilm.ge.com Tue Dec 10 07:10:58 1996

Hello,
DEC sold its tape business to Quantum. We acquire our DLT
from Quantum's reseller and have not found any problem.

DEC's version of DLT may not use "vanila" SCSI driver. I
am not aware of any performance issues with Quantum's DLT.

Let me know what you found out.

Thanks.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Arun Sanghvi
GE-NF&CM

>From prand_at_paul.spu.edu Tue Dec 10 04:50:07 1996

On Mon, 9 Dec 1996, Brian James O'Connor wrote:

> Are the DEC DLT drives as good as the Quantum DLT drives?

Hi Brian,

DEC invented DLT, and later sold the technology (and factory, I think) to
Quantum. As I understand it, DEC DLT drives ARE Quantum DLT drives, with
DEC branding. It must be frustrating for DEC to see DLT becoming so
well-accepted in industry now that it isn't a DEC product!

> Whew what a grab bag of questions, in general I guess, what do people think
> of DLT as the primary backup solution?

We have been using DEC DLT drives as our primary backup means for years,
and are very pleased with them. They are fast and reliable. On Digital
Unix, we use the Advfs Utilities to make clone filesets, and backup the
clones with vdump. It works very nicely. On VMS, we use the backup
utility -- no complaints.

As for stackers and libraries, we haven't needed them, yet. All our
servers have few enough disks that, with compression, we almost always fit
a full backup on one tape.

--
-- Phil Rand <prand_at_spu.edu>, aka <postmaster_at_spu.edu>
-- http://www.spu.edu/users/prand       (206) 281-2428
-- Computer and Information Systems
-- Seattle Pacific University
-- 3307 3rd Ave. W., Seattle, WA  98119
--------------------------------------------------------------------------
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From BAISLEY_at_vssaxp.fnal.gov  Tue Dec 10 03:30:06 1996
I can provide some input.
> Are the DEC DLT drives as good as the Quantum DLT drives?
They're the same.  As far as I know, DEC simply resells the same DLT drive, 
with the possible exception of some minor firmware tweaking (mostly to change 
the drive identification in response to a SCSI query).  Quantum bought the tape 
and (most of the) disk drive unit from DEC a few years back.  The facility and 
engineers in Shrewsbury, Massachusetts haven't changed much since then.  
They've even kept the same mail stop designation, SHR1-4.  They have changed 
the manufacturing operations a good deal, though.  Much of it has moved from 
Colorado to Japan.
> What are your experiences with using Quantum DLTs with a Alphaserver?
Mostly I've used DLT 2000s with VAXes and a DEC 4000 Model 500S, running VMS.  
Aside from a capacity problem early on, due to a manufacturing glitch, which 
was resolved with some impressive support for Quantum, we've been very pleased 
with the DLTs.  Even with the diminished capacity problem, which turned out to 
be misaligned heads which suffered uneven wear, there was never any danger of 
lost data.  The diminished capacity was caused by repeated rewriting of data 
blocks, virtually all of which were readable, even though the writing drive had 
doubts.  It's that fanaticism about data integrity that makes the DLT the only 
real choice in my opinion.  Some of our collaborators from Cornell University 
have also reported great satisfaction with DLTs.  If the decisions were up to 
me (and they're not, alas ;-), I'd stick to DLT 7000s.
Almost all other options are helical-scan drives, which all have the same 
potential for excessive head wear.  We have been a huge customer for 8mm drives 
and tape, due exclusively to media costs (we typically buy ~75,000 cartridges 
per year).  But 8mm gives us plenty of trouble, and if I never saw another one, 
it would be too soon.
The one item I don't know about is what good software there is.  I've just 
moved from VMS to Unix and sorely miss VMS BACKUP.  FermiLab has some freely 
available software for controlling jukeboxes/stackers, if that's of any use to 
you.  Another package called FMB (FerMilab Backup) may be available soon.  It 
automates a good deal of the day-to-day stuff.  You might want to look at:
http://www.fnal.gov/fermitools/
If you're interested in FMB, you might send an inquiry to its author, Marc 
Mengel (mengel_at_fnal.gov), and ask him when it might become available via the 
FermiTools Software Repository.  You can tell him I suggested the question.
(There's the internet in action for you!  Getting an Aussie to pass along a 
suggestion to someone 20 feet away from me!)
I haven't tried it yet, but I suspect that booting the installation CD would be 
enough to allow you to restore a disk from a DLT (or 8mm, or DAT, for that 
matter).
Hope that's helpful.
								Cheers,
								Wayne
http://dcdsv0.fnal.gov:8000/~baisley/
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From WALTERS_at_ad3100.ada.epa.gov  Tue Dec 10 01:50:36 1996
The old DEC DLT were better than the Quantums. DEC sold 
out it tape drive systems to Quantum a couple of years 
ago. When the DLT's work they work well, but when the 
fail (hardware wise) it may take over 4 months to get 
one fixed by Quantum. We have had one drive in the shop 
more often than we have had it on site. On the other end 
one drive has only had a small problem with the tape 
leader in almost 2 years. On the average we have 
experience a failure of a Quantum DLT drive about once 
evry 3-4 months.
They are great in the amount of data they can hold, and 
if you go that way besure to order 2 for every one you 
actually need. One to use and one for a backup. 
Using hindsight I wish we would have gotten HP 4mm DAT's 
We have only had one in the shop in the last five years. 
The tape autoloader  broke shortly after it was out out 
warranty and HP still fixed it for free.
I boils down to the convinence a large tape for backups 
or relability. Hopefully Quantum will get their act 
together and make more reliable tape drives or at least 
get a faster turn around on repairs.
+------------------------------------------------+
| David Walters                                  |
| U.S. Environmental Protection Agency           |
| National Risk Managemant Research Laboratory   |
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| P.O. Box 1198                                  |
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+------------------------------------------------+
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+------------------------------------------------+
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+------------------------------------------------+
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From magill_at_staff.dccs.upenn.edu  Tue Dec 10 01:24:25 1996
>   What about libraries?
We just installed an MTI Infinity 1530 library.
        (28 slots/Breece Hill robotics/2 quantum DLT 20/40 drives)
As I'm writing this, it is doing its first backup of 6 assorted machines
over our new 100mb backup network. Aside from pain in the ass setup problems
(lack of documentation) all has been good, so far.
I've got the Infinity on a 1000A with two 100/10 ethernet interfces.
The "backup network" is a 100 MB 10bT network using 3com switches.
At the moment it inter-connects 6 systems; a mix of 100mb 2100's and
10mb (turbo channel) 3000/400&600. (Including one in another building...
our campus bacbone is 115 miles of fiber)
When finished, it will interconnect a total of 4 2100s, 3 1000s, 2
3000/400, 2 3000/600, and a random assortment of other machines from
Ultrix mips to SUN and HP.
All systems are Network Infrastructure machines (nameservice/timeservice/
news server/central web server/central Postoffice for faculty.)
We're using Digital's Polycenter Network Save and Restore (ie legatto).
T.T.F.N.
William H. Magill                          Senior Systems Administrator
Information Services and Computing (ISC)   University of Pennsylvania
Internet: magill_at_isc.upenn.edu             magill_at_acm.org
          magill_at_upenn.edu                 http://pobox.upenn.edu/~magill/
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From magill_at_staff.dccs.upenn.edu  Tue Dec 10 01:06:06 1996
>   Are the DEC DLT drives as good as the Quantum DLT drives?
There is no longer such a thing as a DEC DLT drive.
DEC sold it's magnetics divion to Quantum about a year/18 months back.
T.T.F.N.
William H. Magill                          Senior Systems Administrator
Information Services and Computing (ISC)   University of Pennsylvania
Internet: magill_at_isc.upenn.edu             magill_at_acm.org
          magill_at_upenn.edu                 http://pobox.upenn.edu/~magill/
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From shollen_at_valhalla.cs.wright.edu  Mon Dec  9 23:51:53 1996
DLT is wonderful.  I think the DEC is probably a relabeled Quantum, though I am
not absolutely sure of that.  We have two DLT jukeboxes, and don't know how we
ever survived without them.  One has a DEC label and one has an SGI label, but
they both look the same.  We are using Networker for backups.
-- 
Sheila Hollenbaugh       Sr. Computer Systems Engineer (O-)
Wright State University  College of Engineering & Computer Science
Dayton, OH 45435         http://www.cs.wright.edu/people/staff/shollen/
shollen_at_cs.wright.edu    Voice: (937) 775-5077  FAX: (937) 775-5009
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From jason_at_dstc.edu.au  Mon Dec  9 23:43:55 1996
In dstc.mail.alpha-osf-managers you write:
>Hi, 
>   we are considering moving to a DLT drive to backup a rapidly
>growing raid array on a AS 2100(4/200).
>Currently its at 12GB, but once we bring the other two ports in to
>use that will probably grow to:
>swxcr 230 raid array(three port pci)
>7x2GB 12GB(current)
>7x4GB 24GB
>7x4GB 24GB
>     ----- 
>      60GB at least
>currently I'm switching tapes all day with a tlz06 dat drive!
>Are the DEC DLT drives as good as the Quantum DLT drives?
dec sold their DLT business to quantum. (just when everyone started
using DLT too, yet another astute dec business decision :-).
dec now just buy from quantum and rebadge.
i'm currently backing up 24G on a 3000/900 using 2 TLZ07s and
an exabyte 8505, and am going to change over to a DLT (TZ88N)
and 2 exabyte 8505s instead, after doing some research. [i wanted
to get 2 DLTs, but we can't afford it :-(]
i *really* like the DLT as a backup solution if you can afford it.
it appears to be faster, more capacity and more robust than exabyte
and way third, dat.  the exabyte mammoth isn't proven yet in the
market unlike the DLT.
-jason
-- 
.jason andrade.......dstc,.pty,.ltd.............jason_at_dstc.edu.au.
.sysadmin............gehrmann laboratories......i just wanna be...
.phn: 61-7-33654307..university.of.queensland...bluemisty.........
.fax: 61-7-33654311..brisbane,.4072,.australia..and barefooted....
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From hl_at_tekla.fi  Mon Dec  9 20:58:37 1996
On Mon, 9 Dec 1996, Brian James O'Connor wrote:
> 
> currently I'm switching tapes all day with a tlz06 dat drive!
Ouch... Hope you don't have anything very valuable on your disks...
> 
> Are the DEC DLT drives as good as the Quantum DLT drives?
As far as I know DEC drives ARE Quantum drives - Quantum is the only
company making those drives.
> 
> Whew what a grab bag of questions, in general I guess, what do people think
> of DLT as the primary backup solution?
> 
General consensus is that they are fast and reliable, although expensive.
> 
> TIA
> boc
--harald
Harald Lundberg <hl_at_tekla.fi>;Tekla Oy,Koronakatu 1,FIN-02210,ESPOO,FINLAND
tel +358-{9-8879449work,9-8039489fax,9-8026752,19-2418013res,50-5578303mob)
>From hmb_at_rosat.mpe-garching.mpg.de  Mon Dec  9 20:26:15 1996
DEC DLT-Tapes are Quantum-Tapes with a better? firmware.
The manufacturer is Quantum, only!
			Sincerely, H. Baumgartner
Max-Planck-Institute of 
Extraterrestrical Physics
Karl-Schwarzschildstr. 1
85740 Garching, Germany
H. Baumgartner 
hmb_at_mpe-garching.mpg.de
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From alan_at_nabeth.cxo.dec.com  Mon Dec  9 19:51:44 1996
>Are the DEC DLT drives as good as the Quantum DLT drives?
Aside from the ones built before we sold our tape and disk
business to Quantum, our DLT drives are Quantum's DLT drives.
Today, Quantum builds all DLT drives, just like Exabyte builds
all 8mm drives.  The main difference is in firmware, which may
be as little as changing the SCSI Inquiry data or as much as
offering different compression algorithms, different error
handling, etc.
The other difference, is qualification and testing.  Our operating
system groups have trouble keeping up with the devices that other
groups in Digital sell, much less those sold by 3rd parties.  The
advantage of a Digital drive is that can feel confident that it
will work, if we say it is supported.  You don't get any sort of
guarantee with a random 3rd party drive, which is basically what
the Quantum version is; untested.
>What are your experiences with using Quantum DLTs with a Alphaserver?
>and apart from the usual UNIX tools(dump,tar) what is the best s/w to
>use with the DLT's , this must include the capablity for restoring
>from a total system crash.(ie if the root partition is fried do I have to
>restore with dump, and am I stuck with having to use the tlzo6 to do this)
If your root file system backup is on a DLT tape, there's no reason
you can restore it from that device.  For root file system backups
and sometimes /usr and /var, using the simplest, supported backup
tool is often best since other tools won't exist on a standalone
system.  Dump is probably best and for the little space used by a
root file system, quite adequate to the task.
The advantages any flavor of DLT drive has over 4mm and 8mm drives
are speed, capacity and reliability.  Dump can pretty steadily write
to the TZ87 class drive (10 GB native) at around 800 KB/sec to 1 MB/sec.
For the TZ88 class drives (20 GB native) it can go faster, but may
be more limited by the drive the data is coming from.  Tar (and cpio)
work well for large files, but slow down when lots of small file have
to be saved.  For small files, the limiting factor becomes how quickly
the files can be opened and close, not how quickly they can be read.
Digital sells a version of Legato's Networker, which is well suited
for backups in networked client/server environments.  The single
server version of this has been included with the base Digital UNIX
software since about V3.2.  I'm sure the major 3rd party backup
products have all tested with DLT drives.
>What about libraries?
We sell four classes of DLT based library/loader; 5 slot, single drive
loaders (TZ875, TZ885), 7 slot, single drive loaders (TZ877, TZ887),
48 slot, 4 drive libraries (TL810, TL812) and 176 to 264 slot, 3-6
drive libraries (TL820, TL822, TL826).  All are reasonably well-
behaved and all should be shipping with software to control the
library; the Media Robot Utility.
>Whew what a grab bag of questions, in general I guess, what do people think
>of DLT as the primary backup solution?
I use a TZ87 on my ULTRIX V4.4 workstation, a TZ85 on my previous
file server and TZ877 on current file server.  I think all the
primary backup devices on larger system in our facility are DLT 
based.  A few individual workstations may have 4mm RDAT instead,
but those typically get backed up over the network if at all.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From wolf_at_pasteur.fr  Mon Dec  9 18:19:10 1996
Brian James O'Connor:
> Are the DEC DLT drives as good as the Quantum DLT drives?
 
They are the same : DEC sold its disks and tape section to Quantum.
> What are your experiences with using Quantum DLTs with a Alphaserver?
> and apart from the usual UNIX tools(dump,tar) what is the best s/w to
> use with the DLT's , this must include the capablity for restoring
> from a total system crash.(ie if the root partition is fried do I have to
> restore with dump, and am I stuck with having to use the tlzo6 to do this)
 
We use Networker on a Odetics robotics with 4 DLT 4000 drives (this is
equivalent to the DEC TL-812 jukebox). I believe that's too much for your
storage capacity yet.
-- 
Christophe Wolfhugel  -+- SIS, Institut Pasteur, Paris
Boulot : wolf_at_pasteur.fr,  $HOME : wolf_at_schnok.fr.net
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From furukawa_at_almond0.kek.jp  Tue Dec 10 12:14:15 1996
Hello Brian,
>>> On Mon, 09 Dec 1996 17:45:37 +1100,  "Brian James O'Connor" <boc_at_ironbark.bendigo.latrobe.edu.au>  wrote;
> Are the DEC DLT drives as good as the Quantum DLT drives?
> 
> What are your experiences with using Quantum DLTs with a Alphaserver?
> and apart from the usual UNIX tools(dump,tar) what is the best s/w to
> use with the DLT's , this must include the capablity for restoring
> from a total system crash.(ie if the root partition is fried do I have to
> restore with dump, and am I stuck with having to use the tlzo6 to do this)
I'm using a 7-cartridge changer of DLT4000 (40GB x 7) from Quantum 
without any problems.
Actually DLT was developed at DEC and DEC sold the division to Quantum. 
Thus they are the same devices.  
Until recently DEC didn't support 40GB drives in the software.  However, 
there are no differences between 40GB and 20GB drives.  I use software 
(NSR) for (20GB x 7) drive and it works for (40GB x 7) drive. 
So they (DEC and Quantum, 20GB and 40GB) are compatible. 
Bye, Kazuro.
-----
Kazuro FURUKAWA <kazuro.furukawa_at_kek.jp>  (or <furukawa_at_kek.jp>)
 Linac,  Natl. Lab. for High Energy Physics (KEK),  Japan
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
From: Huw Davies <H.Davies_at_latrobe.edu.au>
Brian,
>   we are considering moving to a DLT drive to backup a rapidly
>growing raid array on a AS 2100(4/200).
>Currently its at 12GB, but once we bring the other two ports in to
>use that will probably grow to:
>
>swxcr 230 raid array(three port pci)
>7x2GB 12GB(current)
>7x4GB 24GB
>7x4GB 24GB
>     ----- 
>      60GB at least
>
>currently I'm switching tapes all day with a tlz06 dat drive!
>
>Are the DEC DLT drives as good as the Quantum DLT drives?
They are the same thing - Digital sold the rights to manufacture DLT drives
to Quantum.
>What are your experiences with using Quantum DLTs with a Alphaserver?
>and apart from the usual UNIX tools(dump,tar) what is the best s/w to
>use with the DLT's , this must include the capablity for restoring
>from a total system crash.(ie if the root partition is fried do I have to
>restore with dump, and am I stuck with having to use the tlzo6 to do this)
We do all backups for Unix systems under our control to one DLT drive
attached to an Ultrix box (soon to be a Digital Unix box) using public
domain software known as amanda. We have restored complete systems from tape
using amanda.
 Huw Davies                      | e-mail: Huw.Davies_at_latrobe.edu.au
 Information Technology Services | Phone: +61 3 9479 1550  Fax: +61 3 9479 1999
 La Trobe University             | "My Alfas keep me poor in a monetary
 Melbourne Australia 3083        | sense, but rich in so many other ways"
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From Raja Nagaraja, ACTEW Corp, Canberra, Australia
We use DEC DLT to backup data from Alpha 8200 and 2100 an dit is reliable.
We use vdump and tar. There is no problem.
Raja Nagaraja, ACTEW Corp, Canberra, Australia
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>From breree_at_ozemail.com.au  Tue Dec 10 22:19:19 1996
Brian, we are using the DEC DLT drive with the 6 tape stacker.  We get
our daily backup onto 2 tapes, with about 35 GB compresses on each. 
Total backup time is about 8-10 hours, and the backup runs at about
2-3MB/second.  We use the NSR utilities to do our backups and to manage
our tapes.
Day-to-day restores are very easy due to the indexing provided by the
nsr stuff - we restore a 10G database comprising about 3 save sets in
about 3 hours.
We also have a DAT drive to which we do dumps of the root, usr and nsr
binaries and indexes.  
We use the clone feature of advfs to do our database backups - very
handy.  Just down the DB, clone, backup the clone and then unclone.
Oh yes, the DLT is in a Storageworks enclosure, connected to an 8200.
Sorry, I don't know all the model numbers and software titles off hand,
but drop me a line if you like.
Brett.
-- 
Brett Rees
Unix Systems Administrator
email:       breree_at_ozemail.com.au (preferred), breree_at_accsoft.com.au
phone:       +61-414-210-194
home page:   http://www.ozemail.com.au/~breree/  (old and outdated ...)
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
(NOTE THE FOLLOWING IS A SUMMARY ON A RELATED QUESTION)
From: waldorf!karl_at_uunet.uu.net (Karl E. Liliestedt)
Thanks to:
 nabeth.cxo.dec.com!alan
 "William H. Magill" <isc.upenn.edu!magill>
 jbsvax.eksystems.com!barnwell (Barnwell_at_eksystems.com voice 508-303-6905)
 Harald Lundberg <tekla.fi!hl>
 jason andrade <dstc.edu.au!jason>
    ---------------------
    From: nabeth.cxo.dec.com!alan
    
    
    	2.  I've used one (a little) on a DEC OSF/1 V1.3 system...
    
    	    The TZ88 is supported on all the DEC 3000 family starting
    	    with V3.2D.  If you can upgrade (V3.2D-1 is a set of
    	    collected patches), you won't have any trouble with
    	    support.  It is very likely that it will just work on
    	    V3.2C and you won't need to worry about it.
    
    	3.  You should check the product information for the TZ88
    	    to verify that it supports writing CompacTape III at
    	    the density used by the TZ85.  It should be able to
    	    read them, but may not be able to write them.  I don't
    	    recall.
    
    ---------------------
    
    From: "William H. Magill" <isc.upenn.edu!magill>
    
    Digital sold off their magnetics divison to Quantum over a year
    ago....
    So, Quantum is the only manufacturer of DLT drives today, as
    Extabyte is the only manufacturer of 8mm drives. Everybody puts their
    own skin on the devices.
    We use MTI drives. Historically 8mm, but we are just puting an MTI
    Infinity 1530 Tape library into service - 28 slots/Breece Hill
    robotics/two 20-40 DLT tape drives.
    These two drives are "vanilla" Quantums and are running hapilly on a
    kzpaa under 3.2D. We are using the SCSI_CAM layered product (which is
    probably necessary for the Jukebox, but not the drives, but I don't
    know.)
    We're driving the whole thing with NSR 4.2a.
    [lead time on the 20/40 cartidges (Cartridge Tape IV) is now 8-12 weeks!!]
    
    ---------------------
    
    From: jbsvax.eksystems.com!barnwell (Barnwell_at_eksystems.com voice 508-303-6905)
    
    give quantum a call as I think the tz87-tz88 is built by them after
    DEC sold its stoarge group (disks and tapes) to quantum.
    
    	JB
    
    ---------------------
    
    From: Harald Lundberg <tekla.fi!hl>
    
    On Tue, 10 Dec 1996, Karl Liliestedt wrote:
    > 
    > 2) Has anybody had any experience using a TZ88 on a 3000 300LX? Is
    >    the tape drive really not certified for this system and, if it not,
    >    will it be in the near future?
    I think the 88 would probably work, but I think a 300LX is a bit slow
    for the TZ88. It has a speed of 2.5Mb/s, which I think you cannot
    reach unless you have a dedicated scsibus for it. I've been able to
    get about 3.5Mb/s max on my 300's. So to get 2.5 Mb/s you'd need to
    get 5Mb/s trhough your scsi bus. If you don't get full speed the
    drive won't stream.
    > 
    > 
    --harald
    
    ---------------------
    
    From: jason andrade <dstc.edu.au!jason>
    
    In dstc.mail.alpha-osf-managers you write:
    
    >I am currently running Digital UNIX 3.2C on 2 Alpha 3000 300LX systems
    >with 16 GB of disk spread across the Alpha systems and a VAXstation.
    >Our current backup scheme utilizes 8mm tape and I would like it replaced
    >with a DLT drive.
    
    >DEC Direct indicates that the TZ88 is not certified for this system. On
    >a TZ87, they list an "invalid shipping lead time" which the sales
    >person says this usually indicates that the part is being phased out.
    >They are trying to determine if this is the case with the TZ87 drive.
    
    >1) Does anybody know for sure that the TZ87 is being phased out?
    
    >2) Has anybody had any experience using a TZ88 on a 3000 300LX? Is
    >   the tape drive really not certified for this system and, if it not,
    >   will it be in the near future?
    
    one reason it might not be `certified' is that you *really* need to
    put your DLT on a separate scsi bus.  the 300 series only shipped
    with the single scsi bus (unlike the 400/500/600/700/800/900 series
    machines which had 2 separate ones).  if you bought the PMAZ-C (i
    think) dual scsi tc controller and threw the dlt on it, i can't see
    why it wouldn't work.
    i wouldn't get the 87 myself.. the 88 has been out for a while now
    and dec are soon going to ship the TZ89 (otherwise known by quantum
    as the DLT7000 - 35/70G)
    
    -jason
    ---------------------
I finally heard back from DEC Direct. They did confirm that an "invalid
shipping lead time" on the TZ87 meant that they were discontinuing
selling the unit. Before I received their call, I had come to the
conclusion from reading the replys from everybody that I would be
better off with the TZ88.  The discounted price I got from DEC for a
new TZ88 vs the price of a Quantum TZ87 equivalent also helped me make
up my mind.
I am not worried about the speed of it right now because it will mainly
be used for nightly backups of my systems. We will be phasing out the
VAXstation soon and possibly replacing it with a more powerful Alpha.
If the new system doesn't automatically come configured with a TZ88 (or
better), then I will move the one I bought from the 3000 300LX to that
system.
A sales person at Gemini Digital Products Corp. (www.geminidigital.com)
indicated that she can get the CompacTape IV (20/40GB) tapes in a
matter of 1-2 weeks instead of 2-3 months.
  ---------------------
The original question was:
> 
> Date: Tue, 10 Dec 96 15:41 EST
> Subject: DLT for an Alpha 3000 300LX
> 
> I am currently running Digital UNIX 3.2C on 2 Alpha 3000 300LX systems
> with 16 GB of disk spread across the Alpha systems and a VAXstation.
> Our current backup scheme utilizes 8mm tape and I would like it replaced
> with a DLT drive.
> 
> DEC Direct indicates that the TZ88 is not certified for this system. On
> a TZ87, they list an "invalid shipping lead time" which the sales
> person says this usually indicates that the part is being phased out.
> They are trying to determine if this is the case with the TZ87 drive.
> 
> 1) Does anybody know for sure that the TZ87 is being phased out?
> 
> 2) Has anybody had any experience using a TZ88 on a 3000 300LX? Is
>    the tape drive really not certified for this system and, if it not,
>    will it be in the near future?
> 
> 3) Is there some other tape drive alternative I should be looking
>    at compatible with a TZ85? (A client has a TZ85 so it would be
>    convenient if I could exchange data in this format).
> 
Thanks for the help.
	Karl E. Liliestedt              karl_at_msdc.com
	Medical Systems Development Corporation
	Atlanta, GA
Thanks again to all who replied
boc
-- 
------------------------------------------------------------
        Brian O'Connor, Unix Systems Consultant
              Latrobe University,Bendigo
          boc_at_ironbark.bendigo.latrobe.edu.au
------------------------------------------------------------
Received on Mon Dec 16 1996 - 09:10:08 NZDT

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