At 11:25 PM 2007-09-27, Denys Beauchemin wrote:
>Ok. That means your DAT40 is working at the fastest speed possible in
>DDSIII mode with the DDSIII (125M) tapes. So even the faster throughput
>that would come with using DAT40 (150M) tapes is not available through your
>connection. So, if your tape has enough capacity for the backup, your setup
>is optimum and cost-effective.
Yes.
BTW, I mentioned that I believe Neil Harvey uses a dat40 autoloader.
Turns out, so does the customer whose media output statistics I cited.
I just never thought of it as an autoloader since
the backups never spilled over onto a 2nd media
and there was always somebody on-site every day to change/load tapes.
-----Original Message-----
>From: Gilles Schipper [mailto:[log in to unmask]]
>Sent: Thursday, September 27, 2007 10:16 PM
>To: Denys Beauchemin; [log in to unmask]
>Subject: RE: [HP3000-L] dat40
>
>At 11:06 PM 2007-09-27, Denys Beauchemin wrote:
> >Interesting. You should know that if you are using 125Meter tapes, you are
> >actually using the DAT40 as a DDSIII device, not a DAT40 (same if you use
> >the 125M tapes in a DAT72.)
> >
> >The reason for your increased throughput is due to the tape drive turning
> >the tape faster, not because it is writing as a DAT40. The drive would
> >operate faster with a 150M tape.
>
>Not in our experience.
>
>We did extensive testing of the backup environment.
>
>There was absolutely no difference in elapsed
>time when using a 150M tape compared to a 125M
>tape - in both cases to the same dat40 drive.
>
>We wanted to be able to justify the immediate
>purchase of new 150M tapes, but the results of our tests did not support it.
>
>Also, I should point out that Christian's
>original question pertained to the use of the dat40 on a k-class 3k.
>
>I would have been glad to provide capacity
>statistics for a k-class, but I did not have access to them.
>
>In any case, the capacity statistics would be
>identical for a k-class and n-class (or any class).
>
>
> >I would love to read about Neil's experiences. (He's from South Africa,
>not
> >New Zealand, btw.)
>
>Sorry, Neil. My bad.
>
> > One should be able to store a lot of data in such an
> >autoloader.
> >
> >Thanks for the great info.
> >
> >Denys
> >
> >-----Original Message-----
> >From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On Behalf
> >Of Gilles Schipper
> >Sent: Thursday, September 27, 2007 9:56 PM
> >To: [log in to unmask]
> >Subject: Re: [HP3000-L] dat40
> >
> >The following statistics are associated with a
> >HP3000/N4000 full backup to a dat40 tape drive utilizing a dds3 tape.
> >
> >(dat40-native 150-meter tapes are not used
> >because of existing high available inventory of
> >125-meter tapes and no perceived benefit of use
> >of higher-capacity tapes, since full backup fits entirely on a single
>tape).
> >
> >Total backup file data on media: approx. 33gb
> >Total compressed data on media: approx. 10gb
> >
> >So, given the same compression ration of better
> >than 3 to 1, in this example we could assume an
> >additional 20% of file data before we would need
> >to purchase 150-meter tapes or suffer a second media for the backup.
> >
> >A dds3 (aka dat24) tape has a native capacity of
> >12gb; dds4 (aka dat40), 20gb; dds5 (aka dat72), 36gb.
> >
> >I believe Neil Harvey in New Zealand has been
> >utilizing a dat40 autoloader which satisfies a
> >hands-free backup requirement for multi-media backups.
> >
> >If you're still lurking, Neil, please correct me if I'm wrong.
> >
> >A very good reference to the existing and
> >emerging DDS/DAT technology is available at www.datmgm.com.
> >
> >At 09:17 PM 2007-09-27, Denys Beauchemin wrote:
> > >The DAT40 is at the limit of what an SE-SCSI HBA can generate, which is
>why
> > >the DAT72 is no faster. The DAT40 is able to run at less than its rated
> > >speed without falling out of streaming mode. I think it's a combination
>of
> > >the size of the buffer and its ability to adjust.
> > >
> > >I wonder, Gilles, how much are you able to store on a cartridge? Do you
> > >approach 40GB?
> > >
> > >Denys
> > >
> > >
> > >-----Original Message-----
> > >From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On
>Behalf
> > >Of Gilles Schipper
> > >Sent: Thursday, September 27, 2007 10:24 AM
> > >To: [log in to unmask]
> > >Subject: Re: [HP3000-L] dat40
> > >
> > >At 08:46 PM 2007-09-26, Hawkins, Jim (HP, MPE/iX Lab) wrote:
> > > >(top post warning).
> > > >
> > > >Of Denys two suggestions the 50-68 cable to an
> > > >SE-SCSI HBA is more likely to provide a basic
> > > >connection. The HVD/LVD converter would not
> > > >work on k-Class as there are actually some
> > > >driver restrictions in the NIO F/W SCSI HBA
> > > >driver that prevent one from configuring a DDS
> > > >as connected to a A28696A HBA bus (at least as far back as 6.5).
> > > >
> > >The 50-68 cable would be the one if connecting
> > >directly to the se-scsi port of the k-class mfio card.
> > >
> > >If daisy-chaining via other se-scsi devices, the
> > >cable may need to change accordingly to match the connection points.
> > >
> > >
> > > >At the same time "connect ability" does not mean
> > > >"advisability" and never "supportability".
> > > >
> > > >o We didn't test the DAT40 on S900/NIO systems
> > > >because its peak I/O bandwidth (6.0 MB/sec
> > > >Asynchronous) was projected to exceed the
> > > >capabilities of the SE-SCSI HBA (technically 5.0
> > > >Megabytes/sec but really closer to 4
> > > >MB/S). Historically it is not a good idea to
> > > >run tapes at slower than rated speed as it
> > > >causes the tape to drop from streaming mode into
> > > >start/stop mode and excessive wear and/or bad
> > > >performance result. Many tape drives do
> > > >implement variable speed streaming but it wasn't clear that the DAT40
>was
> > >one.
> > > >
> > > >o We never certified any LVD-SCSI interface
> > > >peripherals on the NIO-SE-SCSI HBA. Though all
> > > >Wide LVD devices are technically supposed to be
> > > >able to RUN (READ/WRITE/REWIND) narrow & SE-SCSI
> > > >it is never advisable depend upon manufacturer
> > > >actually testing all device functionality in
> > > >such a hobbled mode. Additionally newer devices
> > > >may spit out "SCSI Standard" information that very old drivers will
>choke
> > >on.
> > > >
> > > >o No idea what the PDC would do if you tried to
> > > >boot from a CSLT on this device. . .
> > > >
> > > >This means that DAT40 is NOT supported by HP via
> > > >SE-SCSI on S900 NIO systems (9x8,9x9,99x &
> > > >earlier). Works fine and is supported by HP on A/N-Class.
> > > >
> > > >So, I'd advise you only use this kind of set-up
> > > >to write data you are willing to lose ;-)!, OR
> > > >at least make sure your back-up application
> > > >vendor is willing to support you. YMMV. . .
> > >Supported or not, it WORKS.
> > >
> > >In fact, it more than works.
> > >
> > >Not only can you boot from it, on a k-class it
> > >performs significantly faster than a dds3 drive.
> > >
> > >On an N-class, a full backup using STORE can
> > >complete in one-third the time when compared to a dds3.
> > >
> > >The bottom line is that the dat40 shines on
> > >virtually all HP3K models, with performance
> > >advantage over the dds3 increasing with increasing HP3K cpu speed.
> > >
> > >Also, the dat72 (aka dds5) also works very well
> > >with the 3k - although its performance is almost equal to the dat40.
> > >
> > >
> > >
> > > >Jim Hawkins
> > > >MPE/iX I/O Architect
> > > >
> > > >
> > > >-----Original Message-----
> > > >From: HP-3000 Systems Discussion
> > > >[mailto:[log in to unmask]] On Behalf Of Denys Beauchemin
> > > >Sent: Wednesday, September 26, 2007 12:32 PM
> > > >To: [log in to unmask]
> > > >Subject: Re: [HP3000-L] dat40
> > > >
> > > >Hello Christian, long time.
> > > >
> > > >I believe the DAT40 is an LVD device which would require you to connect
> >it
> > > >via a 68 to 50 pin cable with high-bit termination or to a 68 bit SCSI
> >port
> > > >on the 3000 using a converter to allow you to switch from HVD (HP3000)
>to
> > > >LVD or SE (DAT40).
> > > >
> > > >Denys
> > > >
> > > >-----Original Message-----
> > > >From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On
> >Behalf
> > > >Of Christian Scott
> > > >Sent: Wednesday, September 26, 2007 1:20 PM
> > > >To: [log in to unmask]
> > > >Subject: [HP3000-L] dat40
> > > >Importance: High
> > > >
> > > >Hi,
> > > >
> > > >
> > > >
> > > >I need to find out if I can connect a dat40 on a hpe3000 k-class
>server,
> >if
> > > >so what are the step involve.
> > > >
> > > >
> > > >
> > > >Thanks,
> > > >
> > > >
> > > >
> > > >Christian Scott
> > > >VP - Development & CTO
> > > >201 Rue Laurier Est
> > > >Suite 630
> > > >Montréal, Québec
> > > >H2T 3E6
> > > >
> > > >Tel: 514-273-0008 x118
> > > >Fax: 514-273-0199
> > > >Email: <mailto:[log in to unmask]> [log in to unmask]
> > > >
> > > >Web: <http://www.softvoyage.com/> www.softvoyage.com
> > > >
> > > >
> > > >
> > > >
> > > >* To join/leave the list, search archives, change list settings, *
> > > >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> > > >
> > > >* To join/leave the list, search archives, change list settings, *
> > > >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> > > >
> > > >* To join/leave the list, search archives, change list settings, *
> > > >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> > > >
> > > >
> > > >
> > > >--
> > > >No virus found in this incoming message.
> > > >Checked by AVG Free Edition.
> > > >Version: 7.5.488 / Virus Database:
> > > >269.13.32/1032 - Release Date: 2007-09-26 8:20 PM
> > >
> >
> >---------------------------------------------------------------------------
> >-
> > >---------------------
> > >Gilles Schipper
> > >GSA Inc.
> > >HP System Administration Specialists
> > >300 John Street, Box 87651 Thornhill, ON Canada L3T 7R4
> > >Voice: 905.889.3000 Fax: 905.889.3001
> > >email: [log in to unmask] web: http://www.gsainc.com
> >
> >---------------------------------------------------------------------------
> >-
> > >---------------------
> > >
> > >* To join/leave the list, search archives, change list settings, *
> > >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> > >
> > >* To join/leave the list, search archives, change list settings, *
> > >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> > >
> > >
> > >
> > >--
> > >No virus found in this incoming message.
> > >Checked by AVG Free Edition.
> > >Version: 7.5.488 / Virus Database:
> > >269.13.32/1032 - Release Date: 2007-09-26 8:20 PM
> >
> >---------------------------------------------------------------------------
>-
> >---------------------
> >Gilles Schipper
> >GSA Inc.
> >HP System Administration Specialists
> >300 John Street, Box 87651 Thornhill, ON Canada L3T 7R4
> >Voice: 905.889.3000 Fax: 905.889.3001
> >email: [log in to unmask] web: http://www.gsainc.com
> >---------------------------------------------------------------------------
>-
> >---------------------
> >
> >* To join/leave the list, search archives, change list settings, *
> >* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
> >
> >
> >
> >
> >--
> >No virus found in this incoming message.
> >Checked by AVG Free Edition.
> >Version: 7.5.488 / Virus Database:
> >269.13.32/1032 - Release Date: 2007-09-26 8:20 PM
>
>----------------------------------------------------------------------------
>---------------------
>Gilles Schipper
>GSA Inc.
>HP System Administration Specialists
>300 John Street, Box 87651 Thornhill, ON Canada L3T 7R4
>Voice: 905.889.3000 Fax: 905.889.3001
>email: [log in to unmask] web: http://www.gsainc.com
>----------------------------------------------------------------------------
>---------------------
>
>* To join/leave the list, search archives, change list settings, *
>* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
>
>
>
>--
>No virus found in this incoming message.
>Checked by AVG Free Edition.
>Version: 7.5.488 / Virus Database:
>269.13.32/1032 - Release Date: 2007-09-26 8:20 PM
-------------------------------------------------------------------------------------------------
Gilles Schipper
GSA Inc.
HP System Administration Specialists
300 John Street, Box 87651 Thornhill, ON Canada L3T 7R4
Voice: 905.889.3000 Fax: 905.889.3001
email: [log in to unmask] web: http://www.gsainc.com
-------------------------------------------------------------------------------------------------
* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
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