From: shah@fnsony.fnal.gov (Hemant Shah)
Newsgroups: comp.sys.sun.admin
Subject: (SUMMARY) dump parameters for Exabyte 8500 tape drive.
Date: 31 Aug 92 14:06:27 GMT
Reply-To: shah@fnalb.fnal.gov
Organization: Fermi National Accelerator Laboratory, Batavia, IL

Earlier I had asked:

>I am looking for "dump" command line options to use with Exabyte 8500 8mm
>tape drive, which options should I use to dump in 2.3 GByte mode, and
>5.0 GByte mode.

and I got few answers and quite a few requests to post the summary of responses.
Thanks to all who replied :-)

Here's the responses I got.

From hanson@fnal.fnal.gov:

|>I assume you're asking about a Sun here?
|>
|>a.  Only supported in 4.1.2 and later (you can munge up the kernel for
|>4.1.1, but I wouldn't bother.)
|>
|>b.  You need to use a different device node.  High density is 8
|>higher than low density.  For example, /dev/rst0 and /dev/rst8.
|>
|>c.  You can just adjust the length of tape parameters for the different
|>proportional density.
|>
|>Look at the man page for dump.  It give numbers for a 8200.  Multiply
|>the length by - oh, maybe 2.1 to get the length for an 8500.

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From gskalla@informatik.Uni-Osnabrueck.DE

We were told to use
        dump -f /dev/st[0-7] ...
to dump in 2.3 GByte mode and
        dump -f /dev/st[8-15] ...
to dump in 5.0 GByte mode.
Reason: from 4.1.1 to 4.1.2 SUN changed the device driver for tapes.
(Just to notice, we did not get this hint from SUN, but from the vendor
of the Exabyte!)

Our system administrator told me, that it works quite fine.

Good luck
        Gernot

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From canver@informatik.uni-ulm.de

We are using the EXB 8500 with 120m tapes (5GB) with the command

        dump 0dsb 54000 24000 126 /dev/hd...

I dunno how to dump in 2.3GB mode (for shorter tapes you just lower the
size appropriately, e.g. 12000 instead of 24000 for 60m tapes (2.5GB), etc.)

hope this helps

cheers,
        Ercu

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From rjq@phys.ksu.edu

 Is this SunOS 4.1.2 or 4.1.1? With 4.1.2 you can choose the mode. From the
st(4S) man page:
     /dev/rst[0-7]
                         Standard EXB-8200 (2GB) Format
     /dev/rst[8-15]
                         EXB-8500 (5GB) Format


 With 4.1.1 I believe you are stuck with what ever the drive defaults to.
I think it defaults to 5GB unless the tape is already written in low density,
and you are part way into the tape (ie the tape drive has had a chance to rec-
ognize the low density).


 I have "archived" several past posts about exabyte tapes, I could bomb your
mailbox with them if you want.

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From jh@cadre.com

What version of the OS are you using?  Support for the 8500 is built into
4.1.2.  I'm still on 4.1.1, though, and in my dump command, I've got a
density (I think) value of 108000 rather than the 54000 used on the 8200.
This was given to me by a tech at Exabyte.  Everything else remains the same.


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Thanks again to all who replied :-)
-- 
-------------------------------------------------------------------------------
Hemant Shah                            | All the opinions expressed are my own
Fermi National Accelerator Laboratory  | and does not necessarily reflect
Systems Integration Group              | those of Fermilab.
E-mail :shah@fnal.fnal.gov             |
 Voice : (708) 840-8071	               | I haven't lost my mind
   Fax : (708) 840-2783                | it's backed on tape somewhere.
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