From:	CRDGW2::CRDGW2::MRGATE::"SMTP::CUNYVM.CUNY.EDU::U0012%DGOGWDG5.BITNET" 30-AUG-1989 18:43
To:	MRGATE::"ARISIA::EVERHART"
Subj:	ZTDRIVER, Exabyte etc.

Message-Id:  <8908302234.AA21460@crdgw1.ge.com>
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Date:    Thu, 31 Aug 1989 00:31:51  +0200
From: "GWDGV1::MOELLER"  <U0012%DGOGWDG5.BITNET@CUNYVM.CUNY.EDU>
To: Everhart@Arisia.decnet
Subject: ZTDRIVER, Exabyte etc.

Glenn,
its going really fast tonight.
Just received your mail, and in the meantime I had sent out all of the stuff
(2 parts first as announced, then the remaining files in 1 part).

Thank you for your offer to provide me with the Spring 89 tape;
I'll put that on hold, since I still expect to receive it some time this year,
being chairman of a little DECUS Germany LUG (the German tape copy path
uses to take months ...). Anyway, I'm not in a hurry, since
so far I have not looked closely at the 88B tapes (received in March),
except for checking [GNUSOFTWARE] and picking up GNU-grep (was not on 88A).
I think I'll wait till we're on VMS V5, since then I'll need the
update to some goodies, in particular the DISM32 disassembler (hope it'll be
there).

I did not mention in the "writeup", that the main reason I did not actually use
ZTDRIVER is that in my experience DECnet/Ethernet (around 50kb/s) is just SLOW,
compared to the speed of 'real' tapes.
So there is no point in tying up a 'served' real tape for the duration
of DECnet data transfer, unless you're really short of disk space.

What I have said in the "writeup" about the EXABYTE must be taken
with caution, since so far it's only a GUESS.
I think I'll ask info-vax if anyone knows better!
If the guess was correct, it would imply that if ever a hard read error
occured on an 8mm tape (holding some LARGE saveset), BACKUP's error recovery
(backspacing 10 or 20 times) would take time on the order of a day ...

Hope to hear from you
        -wjm

Wolfgang J. Moeller, GWDG, D-3400 Goettingen, F.R.Germany | Disclaimer ...
Bitnet/Earn: U0012@DGOGWDG5         Phone: +49 551 201516 | No claim intended
