Well put Denys, I seem to remember a Jim Hawkins from either Ohio, or Indiana that works for HPQ.
Remember HP is always Right until there is nothing LEFT...
12/31/2010
-------------- Original message from Denys Beauchemin <[log in to unmask]>: --------------
> I did not have much time at all to respond to my friend Christian's query so
> I just gave him two alternatives for connectivity with the most likely
> working one being the first one. I even specified the type cable to get.
>
> I figured that if he was going to look at the second one, Christian would
> come back with more questions and during the detailed analysis of how to
> configure it, the issue of lack of drivers for a DDS drive on an HP FWSCSI
> would show up. I surely do not want to disagree with Jim, however, there
> are 2 drivers for tape drives: SCSI_TAPE_DM and SCSI_TAPE2_DM, just as there
> are 2 drivers for disk drives: SCSI_DISC_DM and SCSI_DISK_AND_ARRAY_DM.
>
> The SCSI_TAPE_DM driver is listed for all SCSI-attached DAT drives and these
> would all be attached through the SE (LVD on N-class) SCSI channel. The
> SCSI_TAPE2_DM is listed for the DLT devices, I have also made it work with
> LTO devices. That driver would be used for all SCSI tape drives attached
> through the FWSCSI channel or what is known as HVD (High Voltage
> Differential).
>
> The way I see it, the driver is dependent on the SCSI HBA. If the HBA is a
> wide SCSI, differential or low voltage, one use the SCSI_TAPE2_DM driver for
> tape drives and SCSI_DISK_AND_ARRAY_DM driver for disk drives. If the HBA
> is a narrow SCSI, one use SCSI_TAPE_DM driver for tape drives and
> SCSI_DISC_DM for disk drives.
>
> One can look at the IODFAULT file and scan the generic configuration at the
> end of the file.
>
> So, my thought was that if one uses the SE SCSI channel for a DAT40, one
> would use SCSC_TAPE_DM as the driver. I know that will work, but I also
> know that the DAT40 is much faster than the channel and may suffer shoeshine
> mode because of that. The faster FWSCSI channel would be preferable as it
> could perhaps feed the tape drive faster, but there one would have to use
> the SCSI_TAPE2_DM driver. My belief is that it makes no difference to the
> SCSI driver that a DAT40 is connected on that channel since using SCSI hides
> the device behind a known set of generic commands.
>
> I seriously doubt one could boot from such an arrangement, but as a data
> backup it has much to offer. Of course, testing is key.
>
> And please, let's not use the term "supportability" when we talk about
> devices on the HP3000, that makes me laugh uncontrollably since 11/14/01.
>
> Denys.
>
> -----Original Message-----
> From: HP-3000 Systems Discussion [mailto:[log in to unmask]] On Behalf
> Of Hawkins, Jim (HP, MPE/iX Lab)
> Sent: Wednesday, September 26, 2007 7:47 PM
> To: [log in to unmask]
> Subject: Re: [HP3000-L] dat40
>
> (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).
>
> 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. . .
>
> 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: [log in to unmask]
>
> Web: 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 *
>
> * 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 *
|
