The Unix Heritage Society mailing list
 help / color / Atom feed
* Re: [TUHS] Someone wants to use an exabyte
@ 2019-11-25 18:12 Norman Wilson
  0 siblings, 0 replies; 28+ messages in thread
From: Norman Wilson @ 2019-11-25 18:12 UTC (permalink / raw)
  To: tuhs

Snotty remarks aside, I have a couple of Exabyte drives in my
home world.  They haven't been used for a long time, but when
they were (for some years I used them as a regular backup device)
they worked just fine.

I've pinged the guy.

Norman Wilson
Toronto ON

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-27 20:56     ` Arthur Krewat
@ 2019-11-27 21:25       ` Dave Horsfall
  0 siblings, 0 replies; 28+ messages in thread
From: Dave Horsfall @ 2019-11-27 21:25 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

On Wed, 27 Nov 2019, Arthur Krewat wrote:

[...]

> Very odd circumstance, but block size has a lot to do with trying to 
> read tapes. QIC-150, 8mm, 9-track, I've run into it a lot.

Yep; you tended to use the biggest block size you could, in order to cut 
down on the number of inter-record gaps (and of course, efficiency).

-- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-27 19:31   ` John Foust
@ 2019-11-27 20:56     ` Arthur Krewat
  2019-11-27 21:25       ` Dave Horsfall
  0 siblings, 1 reply; 28+ messages in thread
From: Arthur Krewat @ 2019-11-27 20:56 UTC (permalink / raw)
  To: tuhs

On 11/27/2019 2:31 PM, John Foust wrote:
> I couldn't get any of the DDS-2 to read, either on the original hardware that wrote them, or on a newer STD28000N drive I bought on eBay, a pull from an old Apple server. I could write new tapes on the drive, just couldn't read any old ones. My attempts included reading some tapes I know I'd received from other people (that is, written on other drives) that I know I had been able to read on this hardware back in the day. They wouldn't read, either.
That sounds like a block size issue. Usually telling dd to use a larger 
block than the tape has is fine, but if the default is smaller than 
what's on the tape, it'll fail.

Depending on the drive firmware, the OS support for that particular 
drive, etc, you may or may not get warnings or errors that actually mean 
anything.

A long time ago, I attempted to read some 9-track TOPS-10 tapes using a 
Sun and a 6250 BPI capable tape drive. Nothing would read, it looked 
like there were actually no files on the tape whatsoever. So I gave up, 
but kept the tapes because they contained a lot of personal stuff I had 
done in high school and a few years after.

Years later, I got my hands on a Sun3/280 with 9-track tape drive, and 
attempted to read them again. Same thing, looked like there were no 
files on the tape. Started increasing the block size, and VOILA, got data.

Very odd circumstance, but block size has a lot to do with trying to 
read tapes. QIC-150, 8mm, 9-track, I've run into it a lot.

art k.



^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:52 ` Larry McVoy
  2019-11-24 22:58   ` Rico Pajarola
  2019-11-25  1:41   ` Dave Horsfall
@ 2019-11-27 19:31   ` John Foust
  2019-11-27 20:56     ` Arthur Krewat
  2 siblings, 1 reply; 28+ messages in thread
From: John Foust @ 2019-11-27 19:31 UTC (permalink / raw)
  To: TUHS main list

At 04:52 PM 11/24/2019, Larry McVoy wrote:
>Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of
>building 5 at Sun and into building 9 at SGI and the tapes wouldn't read
>back.

I jumped in on that Twitter thread when I saw it.

Two years ago or so, I attempted to read a couple dozen old backup tapes from the mid 1990s. Half were Archive Python DDS-2 era, written on two different drives that I still had, as 'tar' tapes from SGI workstations. The other half were Exabyte 8500 8mm, some 'tar' from SGI and Linux and Amiga, some 
Windows NTBACKUP.  I set up a fresh Linux box with an Adaptec SCSI card.

I couldn't get any of the DDS-2 to read, either on the original hardware that wrote them, or on a newer STD28000N drive I bought on eBay, a pull from an old Apple server. I could write new tapes on the drive, just couldn't read any old ones. My attempts included reading some tapes I know I'd received from other people (that is, written on other drives) that I know I had been able to read on this hardware back in the day. They wouldn't read, either.

On the other hand, I could read the majority of the Exabytes, even on the original drive I had retained, as well as another I'd bought used in the early 2000s. Some had bad blocks here and there.

The tougher task was trying to find contemporary tools that could process the data stream from an old NTBACKUP, especially a stream with corruption from missing chunks, as I wasn't in the mood to try to rebuild an NT machine with SCSI to let NTBACKUP deal with the drive directly, and I think it would probably fail harder on direct drive errors.

The Amiga-made 'tar' archives were readable by 'tar' but the file time stamps weren't right when burst under Linux. I didn't debug that yet.
 
- John



^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 22:34           ` Dave Horsfall
@ 2019-11-26  1:38             ` Lawrence Stewart
  0 siblings, 0 replies; 28+ messages in thread
From: Lawrence Stewart @ 2019-11-26  1:38 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

I deleted the original message, but I happened to find an Exabyte EX8505 SCSI drive in the basement just now…
Centronics style SCSI sconnectors.  I might have cables somewhere.

Pretty sure I used it in the ‘0’s from a linux system or laptop, since I’ve never had a Sun.

Who wanted one?

-Larry


^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  3:36         ` Larry McVoy
  2019-11-25 22:34           ` Dave Horsfall
  2019-11-25 22:46           ` Dennis Boone
@ 2019-11-25 22:57           ` Henry Bent
  2 siblings, 0 replies; 28+ messages in thread
From: Henry Bent @ 2019-11-25 22:57 UTC (permalink / raw)
  To: Larry McVoy; +Cc: The Eunuchs Hysterical Society

[-- Attachment #1: Type: text/plain, Size: 2075 bytes --]

On Sun, 24 Nov 2019 at 22:37, Larry McVoy <lm@mcvoy.com> wrote:

> On Mon, Nov 25, 2019 at 02:29:02PM +1100, Dave Horsfall wrote:
> > On Mon, 25 Nov 2019, George Michaelson wrote:
> >
> > >I just failed with a Sun DAT drive. Cable and card bought online,
> > >recognized by the mt command, but all it does is eject tapes.
> >
> > They're worse than 9-track tapes, and that's saying something :-)
>
> Really?  Are we talking about those tapes that looked like reel to reel
> audio tapes but bigger?  Like this?
>
> https://www.canajunfinances.com/wp-content/uploads/2013/04/9-Track-Tape.jpg
>
> Because those are 1000x more reliable than an exabyte tape, they just
> worked.  Pretty much no matter what, you can spool up that tape and it
> will read.  30 years later it will read.
>
> Exabyte won't read 20 minutes later.
>

I think that certain amount of the reliability issue, as far as both the
tapes and the drives are concerned, has to do with scale.  Those 8mm
Exabyte tapes (DDS tapes, too) are much thinner and hence more easily
damaged than a large 9 track reel.  If thin tape in a cartridge gets fouled
up past a certain point, forget it, there's no salvaging that cartridge.
If open reel tape gets damaged and you really need what's on it you can
hope that the mechanism can read past the damaged part (a possibility), or
as a last resort you could make a careful splice and then attempt to
retrieve the rest of the data.

One of the other issues, totally independent of tape, is the rubber chosen
by the manufacturers for the drive belts and rollers.  Some rubber, stored
properly, will still be in usable shape after twenty or thirty years.  The
rubber on the rollers of my Sun QIC-150 drive?  A goopy mess which rendered
the drive useless as well as a tape.

But yeah, about 15 years ago I was asked to retrieve some data from Exabyte
8200 tapes that had been written 10 years prior.  I went through three
drives and countless hours of frustration just to read a half-dozen tapes
with some really important information on them.  "Archive format" indeed.

-Henry

[-- Attachment #2: Type: text/html, Size: 2681 bytes --]

<div dir="ltr"><div dir="ltr">On Sun, 24 Nov 2019 at 22:37, Larry McVoy &lt;<a href="mailto:lm@mcvoy.com">lm@mcvoy.com</a>&gt; wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Mon, Nov 25, 2019 at 02:29:02PM +1100, Dave Horsfall wrote:<br>
&gt; On Mon, 25 Nov 2019, George Michaelson wrote:<br>
&gt; <br>
&gt; &gt;I just failed with a Sun DAT drive. Cable and card bought online,<br>
&gt; &gt;recognized by the mt command, but all it does is eject tapes.<br>
&gt; <br>
&gt; They&#39;re worse than 9-track tapes, and that&#39;s saying something :-)<br>
<br>
Really?  Are we talking about those tapes that looked like reel to reel<br>
audio tapes but bigger?  Like this?<br>
<br>
<a href="https://www.canajunfinances.com/wp-content/uploads/2013/04/9-Track-Tape.jpg" rel="noreferrer" target="_blank">https://www.canajunfinances.com/wp-content/uploads/2013/04/9-Track-Tape.jpg</a><br>
<br>
Because those are 1000x more reliable than an exabyte tape, they just <br>
worked.  Pretty much no matter what, you can spool up that tape and it<br>
will read.  30 years later it will read.<br>
<br>
Exabyte won&#39;t read 20 minutes later.<br></blockquote><div><br></div><div>I think that certain amount of the reliability issue, as far as both the tapes and the drives are concerned, has to do with scale.  Those 8mm Exabyte tapes (DDS tapes, too) are much thinner and hence more easily damaged than a large 9 track reel.  If thin tape in a cartridge gets fouled up past a certain point, forget it, there&#39;s no salvaging that cartridge.  If open reel tape gets damaged and you really need what&#39;s on it you can hope that the mechanism can read past the damaged part (a possibility), or as a last resort you could make a careful splice and then attempt to retrieve the rest of the data.<br></div><div><br></div><div>One of the other issues, totally independent of tape, is the rubber chosen by the manufacturers for the drive belts and rollers.  Some rubber, stored properly, will still be in usable shape after twenty or thirty years.  The rubber on the rollers of my Sun QIC-150 drive?  A goopy mess which rendered the drive useless as well as a tape.</div><div><br></div><div>But yeah, about 15 years ago I was asked to retrieve some data from Exabyte 8200 tapes that had been written 10 years prior.  I went through three drives and countless hours of frustration just to read a half-dozen tapes with some really important information on them.  &quot;Archive format&quot; indeed.<br></div><div><br></div><div>-Henry<br></div></div></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  3:36         ` Larry McVoy
  2019-11-25 22:34           ` Dave Horsfall
@ 2019-11-25 22:46           ` Dennis Boone
  2019-11-25 22:57           ` Henry Bent
  2 siblings, 0 replies; 28+ messages in thread
From: Dennis Boone @ 2019-11-25 22:46 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

 > I'd be surprised if a 9-track was 100% readable 30 years on.

I've read quite a few of them, including some stored in crappy
conditions, without errors.  The stuff is pretty robust.  Sticky shed is
an issue, for which there are a number of palliative techniques.

De

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  3:36         ` Larry McVoy
@ 2019-11-25 22:34           ` Dave Horsfall
  2019-11-26  1:38             ` Lawrence Stewart
  2019-11-25 22:46           ` Dennis Boone
  2019-11-25 22:57           ` Henry Bent
  2 siblings, 1 reply; 28+ messages in thread
From: Dave Horsfall @ 2019-11-25 22:34 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

On Sun, 24 Nov 2019, Larry McVoy wrote:

>> They're worse than 9-track tapes, and that's saying something :-)
>
> Really?  Are we talking about those tapes that looked like reel to reel 
> audio tapes but bigger?  Like this?
>
> https://www.canajunfinances.com/wp-content/uploads/2013/04/9-Track-Tape.jpg

Yes.

> Because those are 1000x more reliable than an exabyte tape, they just 
> worked.  Pretty much no matter what, you can spool up that tape and it 
> will read.  30 years later it will read.

Please read my reply about print-through, build-up of gunk, etc.  I'd be 
surprised if a 9-track was 100% readable 30 years on.

> Exabyte won't read 20 minutes later.

Bit of an exaggeration, but yes in principle.

-- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:45             ` Larry McVoy
  2019-11-25 17:49               ` Jon Steinhart
  2019-11-25 18:34               ` Arthur Krewat
@ 2019-11-25 21:38               ` Dave Horsfall
  2 siblings, 0 replies; 28+ messages in thread
From: Dave Horsfall @ 2019-11-25 21:38 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

On Mon, 25 Nov 2019, Larry McVoy wrote:

> It's no secret that I enjoyed my years at Sun, but I can't defend these 
> drives, I had the same experience.  When I look back on it, the only 
> tapes that I remember being reliable where the 9 track reel to reel and 
> the QIC-150.  Once it got to GB sized tapes, everything seemed like 
> crap.

I see you've never enjoyed the thrills of "print through" on the 9-tracks, 
nor the build-up of gunk (the then Australian Atomic Energy Commission had 
a "tape cleaner" whereby the tape was basically run over a sharp blade).

And as for the QIC-150 drive that would occasionally fall back to what I 
would call a QIC-75 when presented with media previously written at a 
lower density...  I recall that an EPROM upgrade fixed that.

-- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 21:11                   ` ron
@ 2019-11-25 21:30                     ` John P. Linderman
  0 siblings, 0 replies; 28+ messages in thread
From: John P. Linderman @ 2019-11-25 21:30 UTC (permalink / raw)
  To: Ron Natalie; +Cc: The Unix Heritage Society

[-- Attachment #1: Type: text/plain, Size: 2945 bytes --]

Fair enough, Ron. I recall that we had to replace Exabyte drives more often
than 9-track drives. On the other hand, I don't recall ever having an
Exabyte tape go bad, or being unable to restore a lost file (or entire
drive). Replacing a drive was chump change compared to losing a drive.
Plus, the Exabyte tapes were compact, and could easily have a paper label
inserted to indicate what was on them when hundreds were stored
side-by-side on a shelf. My labels were roundly mocked by Tom Limoncelli in
one of his Sysadmin books, but when a user came in wanting a file restored,
being able to identify which tape contained the most recent backup was no
laughing matter (to the user).

On Mon, Nov 25, 2019 at 4:12 PM <ron@ronnatalie.com> wrote:

> Our problem wasn’t so much that the Exabyte tapes would go bad as the
> drives themselves would keel over on a regular basis.   It’s pretty much
> what drove us away from them.    The intelligence community did a lot of
> studies on archival storage devices.    The fundamental truth was to keep
> refreshed in the online domain rather than spending ages on static media.
>
>
>
>
>
> *From:* TUHS <tuhs-bounces@minnie.tuhs.org> *On Behalf Of *John P.
> Linderman
> *Sent:* Monday, November 25, 2019 4:08 PM
> *To:* Arthur Krewat <krewat@kilonet.net>
> *Cc:* The Unix Heritage Society <tuhs@minnie.tuhs.org>
> *Subject:* Re: [TUHS] Someone wants to use an exabyte
>
>
>
> I'm not an expert on mag tapes, but it makes sense to me that 9-track
> tapes, where the tracks "line up" when the tape is wound onto a reel,
> suffer more "print-through" than helical scan tapes, where tracks are not
> aligned with those under them on a reel. I recall a suggestion that 9-track
> tapes should be mounted and rewound once in a while, to reduce
> print-through. We used Exabytes for disk backups for years, back when tape
> capacity exceeded disk capacity. I doubt I'll see that again, but, as noted
> I'm not an expert on mag tapes.
>
>
>
> On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat <krewat@kilonet.net> wrote:
>
> On 11/25/2019 12:45 PM, Larry McVoy wrote:
> > On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
> >> PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.
> > It's no secret that I enjoyed my years at Sun, but I can't defend these
> > drives, I had the same experience.  When I look back on it, the only
> > tapes that I remember being reliable where the 9 track reel to reel
> > and the QIC-150.  Once it got to GB sized tapes, everything seemed
> > like crap.
> >
>
> The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked
> with them for the past 13 years, I can definitely say, are quit awesome.
>
> DLT tapes and especially robots, well, it took HP about 5 years to get
> the firmware right for a certain robot, the model of which, I don't
> recall ...
>
> art k.
>
>

[-- Attachment #2: Type: text/html, Size: 4552 bytes --]

<div dir="ltr"><div class="gmail_default" style="font-size:small">Fair enough, Ron. I recall that we had to replace Exabyte drives more often than 9-track drives. On the other hand, I don&#39;t recall ever having an Exabyte tape go bad, or being unable to restore a lost file (or entire drive). Replacing a drive was chump change compared to losing a drive. Plus, the Exabyte tapes were compact, and could easily have a paper label inserted to indicate what was on them when hundreds were stored side-by-side on a shelf. My labels were roundly mocked by Tom Limoncelli in one of his Sysadmin books, but when a user came in wanting a file restored, being able to identify which tape contained the most recent backup was no laughing matter (to the user).</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 25, 2019 at 4:12 PM &lt;<a href="mailto:ron@ronnatalie.com">ron@ronnatalie.com</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div lang="EN-US"><div class="gmail-m_-4157321810315177091WordSection1"><p class="MsoNormal">Our problem wasn’t so much that the Exabyte tapes would go bad as the drives themselves would keel over on a regular basis.   It’s pretty much what drove us away from them.    The intelligence community did a lot of studies on archival storage devices.    The fundamental truth was to keep refreshed in the online domain rather than spending ages on static media.<u></u><u></u></p><p class="MsoNormal"><u></u> <u></u></p><p class="MsoNormal">  <u></u><u></u></p><div style="border-top:none;border-right:none;border-bottom:none;border-left:1.5pt solid blue;padding:0in 0in 0in 4pt"><div><div style="border-right:none;border-bottom:none;border-left:none;border-top:1pt solid rgb(225,225,225);padding:3pt 0in 0in"><p class="MsoNormal"><b>From:</b> TUHS &lt;<a href="mailto:tuhs-bounces@minnie.tuhs.org" target="_blank">tuhs-bounces@minnie.tuhs.org</a>&gt; <b>On Behalf Of </b>John P. Linderman<br><b>Sent:</b> Monday, November 25, 2019 4:08 PM<br><b>To:</b> Arthur Krewat &lt;<a href="mailto:krewat@kilonet.net" target="_blank">krewat@kilonet.net</a>&gt;<br><b>Cc:</b> The Unix Heritage Society &lt;<a href="mailto:tuhs@minnie.tuhs.org" target="_blank">tuhs@minnie.tuhs.org</a>&gt;<br><b>Subject:</b> Re: [TUHS] Someone wants to use an exabyte<u></u><u></u></p></div></div><p class="MsoNormal"><u></u> <u></u></p><div><div><p class="MsoNormal"><span style="font-size:12pt">I&#39;m not an expert on mag tapes, but it makes sense to me that 9-track tapes, where the tracks &quot;line up&quot; when the tape is wound onto a reel, suffer more &quot;print-through&quot; than helical scan tapes, where tracks are not aligned with those under them on a reel. I recall a suggestion that 9-track tapes should be mounted and rewound once in a while, to reduce print-through. We used Exabytes for disk backups for years, back when tape capacity exceeded disk capacity. I doubt I&#39;ll see that again, but, as noted I&#39;m not an expert on mag tapes.<u></u><u></u></span></p></div></div><p class="MsoNormal"><u></u> <u></u></p><div><div><p class="MsoNormal">On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat &lt;<a href="mailto:krewat@kilonet.net" target="_blank">krewat@kilonet.net</a>&gt; wrote:<u></u><u></u></p></div><blockquote style="border-top:none;border-right:none;border-bottom:none;border-left:1pt solid rgb(204,204,204);padding:0in 0in 0in 6pt;margin-left:4.8pt;margin-right:0in"><p class="MsoNormal" style="margin-bottom:12pt">On 11/25/2019 12:45 PM, Larry McVoy wrote:<br>&gt; On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:<br>&gt;&gt; PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.<br>&gt; It&#39;s no secret that I enjoyed my years at Sun, but I can&#39;t defend these<br>&gt; drives, I had the same experience.  When I look back on it, the only<br>&gt; tapes that I remember being reliable where the 9 track reel to reel<br>&gt; and the QIC-150.  Once it got to GB sized tapes, everything seemed<br>&gt; like crap.<br>&gt;<br><br>The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked <br>with them for the past 13 years, I can definitely say, are quit awesome.<br><br>DLT tapes and especially robots, well, it took HP about 5 years to get <br>the firmware right for a certain robot, the model of which, I don&#39;t <br>recall ...<br><br>art k.<u></u><u></u></p></blockquote></div></div></div></div></blockquote></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 21:08                 ` John P. Linderman
@ 2019-11-25 21:11                   ` ron
  2019-11-25 21:30                     ` John P. Linderman
  0 siblings, 1 reply; 28+ messages in thread
From: ron @ 2019-11-25 21:11 UTC (permalink / raw)
  To: The Unix Heritage Society

[-- Attachment #1: Type: text/plain, Size: 2111 bytes --]

Our problem wasn’t so much that the Exabyte tapes would go bad as the drives themselves would keel over on a regular basis.   It’s pretty much what drove us away from them.    The intelligence community did a lot of studies on archival storage devices.    The fundamental truth was to keep refreshed in the online domain rather than spending ages on static media.

 

  

From: TUHS <tuhs-bounces@minnie.tuhs.org> On Behalf Of John P. Linderman
Sent: Monday, November 25, 2019 4:08 PM
To: Arthur Krewat <krewat@kilonet.net>
Cc: The Unix Heritage Society <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] Someone wants to use an exabyte

 

I'm not an expert on mag tapes, but it makes sense to me that 9-track tapes, where the tracks "line up" when the tape is wound onto a reel, suffer more "print-through" than helical scan tapes, where tracks are not aligned with those under them on a reel. I recall a suggestion that 9-track tapes should be mounted and rewound once in a while, to reduce print-through. We used Exabytes for disk backups for years, back when tape capacity exceeded disk capacity. I doubt I'll see that again, but, as noted I'm not an expert on mag tapes.

 

On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat <krewat@kilonet.net <mailto:krewat@kilonet.net> > wrote:

On 11/25/2019 12:45 PM, Larry McVoy wrote:
> On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
>> PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.
> It's no secret that I enjoyed my years at Sun, but I can't defend these
> drives, I had the same experience.  When I look back on it, the only
> tapes that I remember being reliable where the 9 track reel to reel
> and the QIC-150.  Once it got to GB sized tapes, everything seemed
> like crap.
>

The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked 
with them for the past 13 years, I can definitely say, are quit awesome.

DLT tapes and especially robots, well, it took HP about 5 years to get 
the firmware right for a certain robot, the model of which, I don't 
recall ...

art k.


[-- Attachment #2: Type: text/html, Size: 4809 bytes --]

<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
	{font-family:"Cambria Math";
	panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
	{font-family:Calibri;
	panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
	{margin:0in;
	margin-bottom:.0001pt;
	font-size:11.0pt;
	font-family:"Calibri",sans-serif;}
a:link, span.MsoHyperlink
	{mso-style-priority:99;
	color:blue;
	text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
	{mso-style-priority:99;
	color:purple;
	text-decoration:underline;}
p.msonormal0, li.msonormal0, div.msonormal0
	{mso-style-name:msonormal;
	mso-margin-top-alt:auto;
	margin-right:0in;
	mso-margin-bottom-alt:auto;
	margin-left:0in;
	font-size:11.0pt;
	font-family:"Calibri",sans-serif;}
span.EmailStyle18
	{mso-style-type:personal-reply;
	font-family:"Calibri",sans-serif;
	color:windowtext;}
.MsoChpDefault
	{mso-style-type:export-only;
	font-family:"Calibri",sans-serif;}
@page WordSection1
	{size:8.5in 11.0in;
	margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
	{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Our problem wasn’t so much that the Exabyte tapes would go bad as the drives themselves would keel over on a regular basis.   It’s pretty much what drove us away from them.    The intelligence community did a lot of studies on archival storage devices.    The fundamental truth was to keep refreshed in the online domain rather than spending ages on static media.<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>  <o:p></o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> TUHS &lt;tuhs-bounces@minnie.tuhs.org&gt; <b>On Behalf Of </b>John P. Linderman<br><b>Sent:</b> Monday, November 25, 2019 4:08 PM<br><b>To:</b> Arthur Krewat &lt;krewat@kilonet.net&gt;<br><b>Cc:</b> The Unix Heritage Society &lt;tuhs@minnie.tuhs.org&gt;<br><b>Subject:</b> Re: [TUHS] Someone wants to use an exabyte<o:p></o:p></p></div></div><p class=MsoNormal><o:p>&nbsp;</o:p></p><div><div><p class=MsoNormal><span style='font-size:12.0pt'>I'm not an expert on mag tapes, but it makes sense to me that 9-track tapes, where the tracks &quot;line up&quot; when the tape is wound onto a reel, suffer more &quot;print-through&quot; than helical scan tapes, where tracks are not aligned with those under them on a reel. I recall a suggestion that 9-track tapes should be mounted and rewound once in a while, to reduce print-through. We used Exabytes for disk backups for years, back when tape capacity exceeded disk capacity. I doubt I'll see that again, but, as noted I'm not an expert on mag tapes.<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p>&nbsp;</o:p></p><div><div><p class=MsoNormal>On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat &lt;<a href="mailto:krewat@kilonet.net">krewat@kilonet.net</a>&gt; wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><p class=MsoNormal style='margin-bottom:12.0pt'>On 11/25/2019 12:45 PM, Larry McVoy wrote:<br>&gt; On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:<br>&gt;&gt; PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.<br>&gt; It's no secret that I enjoyed my years at Sun, but I can't defend these<br>&gt; drives, I had the same experience.&nbsp; When I look back on it, the only<br>&gt; tapes that I remember being reliable where the 9 track reel to reel<br>&gt; and the QIC-150.&nbsp; Once it got to GB sized tapes, everything seemed<br>&gt; like crap.<br>&gt;<br><br>The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked <br>with them for the past 13 years, I can definitely say, are quit awesome.<br><br>DLT tapes and especially robots, well, it took HP about 5 years to get <br>the firmware right for a certain robot, the model of which, I don't <br>recall ...<br><br>art k.<o:p></o:p></p></blockquote></div></div></div></body></html>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 18:34               ` Arthur Krewat
@ 2019-11-25 21:08                 ` John P. Linderman
  2019-11-25 21:11                   ` ron
  0 siblings, 1 reply; 28+ messages in thread
From: John P. Linderman @ 2019-11-25 21:08 UTC (permalink / raw)
  To: Arthur Krewat; +Cc: The Unix Heritage Society

[-- Attachment #1: Type: text/plain, Size: 1436 bytes --]

I'm not an expert on mag tapes, but it makes sense to me that 9-track
tapes, where the tracks "line up" when the tape is wound onto a reel,
suffer more "print-through" than helical scan tapes, where tracks are not
aligned with those under them on a reel. I recall a suggestion that 9-track
tapes should be mounted and rewound once in a while, to reduce
print-through. We used Exabytes for disk backups for years, back when tape
capacity exceeded disk capacity. I doubt I'll see that again, but, as noted
I'm not an expert on mag tapes.

On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat <krewat@kilonet.net> wrote:

> On 11/25/2019 12:45 PM, Larry McVoy wrote:
> > On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
> >> PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.
> > It's no secret that I enjoyed my years at Sun, but I can't defend these
> > drives, I had the same experience.  When I look back on it, the only
> > tapes that I remember being reliable where the 9 track reel to reel
> > and the QIC-150.  Once it got to GB sized tapes, everything seemed
> > like crap.
> >
>
> The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked
> with them for the past 13 years, I can definitely say, are quit awesome.
>
> DLT tapes and especially robots, well, it took HP about 5 years to get
> the firmware right for a certain robot, the model of which, I don't
> recall ...
>
> art k.
>
>

[-- Attachment #2: Type: text/html, Size: 1906 bytes --]

<div dir="ltr"><div class="gmail_default" style="font-size:small">I&#39;m not an expert on mag tapes, but it makes sense to me that 9-track tapes, where the tracks &quot;line up&quot; when the tape is wound onto a reel, suffer more &quot;print-through&quot; than helical scan tapes, where tracks are not aligned with those under them on a reel. I recall a suggestion that 9-track tapes should be mounted and rewound once in a while, to reduce print-through. We used Exabytes for disk backups for years, back when tape capacity exceeded disk capacity. I doubt I&#39;ll see that again, but, as noted I&#39;m not an expert on mag tapes.</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 25, 2019 at 1:35 PM Arthur Krewat &lt;<a href="mailto:krewat@kilonet.net">krewat@kilonet.net</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On 11/25/2019 12:45 PM, Larry McVoy wrote:<br>
&gt; On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:<br>
&gt;&gt; PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.<br>
&gt; It&#39;s no secret that I enjoyed my years at Sun, but I can&#39;t defend these<br>
&gt; drives, I had the same experience.  When I look back on it, the only<br>
&gt; tapes that I remember being reliable where the 9 track reel to reel<br>
&gt; and the QIC-150.  Once it got to GB sized tapes, everything seemed<br>
&gt; like crap.<br>
&gt;<br>
<br>
The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked <br>
with them for the past 13 years, I can definitely say, are quit awesome.<br>
<br>
DLT tapes and especially robots, well, it took HP about 5 years to get <br>
the firmware right for a certain robot, the model of which, I don&#39;t <br>
recall ...<br>
<br>
art k.<br>
<br>
</blockquote></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:45             ` Larry McVoy
  2019-11-25 17:49               ` Jon Steinhart
@ 2019-11-25 18:34               ` Arthur Krewat
  2019-11-25 21:08                 ` John P. Linderman
  2019-11-25 21:38               ` Dave Horsfall
  2 siblings, 1 reply; 28+ messages in thread
From: Arthur Krewat @ 2019-11-25 18:34 UTC (permalink / raw)
  To: Larry McVoy; +Cc: tuhs

On 11/25/2019 12:45 PM, Larry McVoy wrote:
> On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
>> PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.
> It's no secret that I enjoyed my years at Sun, but I can't defend these
> drives, I had the same experience.  When I look back on it, the only
> tapes that I remember being reliable where the 9 track reel to reel
> and the QIC-150.  Once it got to GB sized tapes, everything seemed
> like crap.
>

The Exabyte 5GB and up stuff was pretty good. LTOs, after having worked 
with them for the past 13 years, I can definitely say, are quit awesome.

DLT tapes and especially robots, well, it took HP about 5 years to get 
the firmware right for a certain robot, the model of which, I don't 
recall ...

art k.


^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:07         ` Al Kossow
  2019-11-25 17:40           ` Arthur Krewat
@ 2019-11-25 18:29           ` Warner Losh
  1 sibling, 0 replies; 28+ messages in thread
From: Warner Losh @ 2019-11-25 18:29 UTC (permalink / raw)
  To: Al Kossow; +Cc: TUHS main list

[-- Attachment #1: Type: text/plain, Size: 1652 bytes --]

On Mon, Nov 25, 2019 at 10:07 AM Al Kossow <aek@bitsavers.org> wrote:

>
>
> On 11/24/19 7:24 PM, Larry McVoy wrote:
> > So that sounds like a different problem.  People correct me if I'm
> > wrong but the exabyte drives seemed to have a head alignment problem.
>
> They are 8mm helical-head drives. they wouldn't go out of alignment by
> bumping them, the worse would be the tape would lose tension if you
> smacked the tensioning arms hard enough
>
> They do have a lot of rubber parts inside.
> Rollers crack and belts go soft. I have several dozen dead EX8200s from
> that.
>
> I have a whole box of 8mm backup tapes that just came in, and a small
> number of working drives. The Linux software I wrote to do 9 track tape
> recovery
> from a SCSI 9 track drive works just fine on an Exabyte.
>
> And I'm not offering to read Jason's mystery reels.
>

IIRC, the main issue from back in the day was different densities on the
same form-factor tapes. So if you want to the same model 8mm drive, it
works, if you go to a different (older?) model, it wouldn't. Eg, going from
the 8500 -> 8200 caused problems due to data density issues. IIRC, you
could write low density data tapes on the 8500 for interchange with the
8200, but it wasn't the default on some platforms?

But it's been a long time and my memory is hazy... so long that Exabyte
went bankrupt, several new tenants tried to rent the old space, the
developer that bought it at the exabyte firesale wen bankrupt too and the
new developers that bought it have torn down the old Exabyte offices in
Boulder and replaced it with a set of luxury apartments... I could be
misremembering...

Warner

[-- Attachment #2: Type: text/html, Size: 2118 bytes --]

<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 25, 2019 at 10:07 AM Al Kossow &lt;<a href="mailto:aek@bitsavers.org">aek@bitsavers.org</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
<br>
On 11/24/19 7:24 PM, Larry McVoy wrote:<br>
&gt; So that sounds like a different problem.  People correct me if I&#39;m<br>
&gt; wrong but the exabyte drives seemed to have a head alignment problem.<br>
<br>
They are 8mm helical-head drives. they wouldn&#39;t go out of alignment by<br>
bumping them, the worse would be the tape would lose tension if you<br>
smacked the tensioning arms hard enough<br>
<br>
They do have a lot of rubber parts inside.<br>
Rollers crack and belts go soft. I have several dozen dead EX8200s from that.<br>
<br>
I have a whole box of 8mm backup tapes that just came in, and a small<br>
number of working drives. The Linux software I wrote to do 9 track tape recovery<br>
from a SCSI 9 track drive works just fine on an Exabyte.<br>
<br>
And I&#39;m not offering to read Jason&#39;s mystery reels.<br></blockquote><div><br></div><div>IIRC, the main issue from back in the day was different densities on the same form-factor tapes. So if you want to the same model 8mm drive, it works, if you go to a different (older?) model, it wouldn&#39;t. Eg, going from the 8500 -&gt; 8200 caused problems due to data density issues. IIRC, you could write low density data tapes on the 8500 for interchange with the 8200, but it wasn&#39;t the default on some platforms?</div><div><br></div><div>But it&#39;s been a long time and my memory is hazy... so long that Exabyte went bankrupt, several new tenants tried to rent the old space, the developer that bought it at the exabyte firesale wen bankrupt too and the new developers that bought it have torn down the old Exabyte offices in Boulder and replaced it with a set of luxury apartments... I could be misremembering...</div><div><br></div><div>Warner</div></div></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:45             ` Larry McVoy
@ 2019-11-25 17:49               ` Jon Steinhart
  2019-11-25 18:34               ` Arthur Krewat
  2019-11-25 21:38               ` Dave Horsfall
  2 siblings, 0 replies; 28+ messages in thread
From: Jon Steinhart @ 2019-11-25 17:49 UTC (permalink / raw)
  To: tuhs

Larry McVoy writes:
> On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
> > PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.
>
> It's no secret that I enjoyed my years at Sun, but I can't defend these
> drives, I had the same experience.  When I look back on it, the only
> tapes that I remember being reliable where the 9 track reel to reel
> and the QIC-150.  Once it got to GB sized tapes, everything seemed
> like crap.

Well, I'd say even from an audio perspective DATs were crap.  Just not a
good technology.  Before DATs I used Beta decks with a PCM-601ES for
audio; was better than DAT probably because of the larger geometry.  Same
reason that 9 track tapes last a long time - larger features.

In weird DAT tech, I have (although it's currently loaned out), one of the
SGI Archive Python drives that allows the DDS layer to be turned off so
that audio can be read and written directly.

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:40           ` Arthur Krewat
@ 2019-11-25 17:45             ` Larry McVoy
  2019-11-25 17:49               ` Jon Steinhart
                                 ` (2 more replies)
  0 siblings, 3 replies; 28+ messages in thread
From: Larry McVoy @ 2019-11-25 17:45 UTC (permalink / raw)
  To: Arthur Krewat; +Cc: tuhs

On Mon, Nov 25, 2019 at 12:40:22PM -0500, Arthur Krewat wrote:
> PS: DAT 4mm tape drives, especially whatever Sun was using, were awful.

It's no secret that I enjoyed my years at Sun, but I can't defend these
drives, I had the same experience.  When I look back on it, the only
tapes that I remember being reliable where the 9 track reel to reel
and the QIC-150.  Once it got to GB sized tapes, everything seemed
like crap.

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25 17:07         ` Al Kossow
@ 2019-11-25 17:40           ` Arthur Krewat
  2019-11-25 17:45             ` Larry McVoy
  2019-11-25 18:29           ` Warner Losh
  1 sibling, 1 reply; 28+ messages in thread
From: Arthur Krewat @ 2019-11-25 17:40 UTC (permalink / raw)
  To: tuhs

A few years back, I decided to go through my stack of 8mm 
Exabyte-written tapes... An early Exabyte 8200 2GB Exabyte drive was 
useless. A 2/5G drive worked.

There were errors on one or two tapes. But each and every one was an 
analog 8mm video tape, not a real data tape. And I was able to splice 
the backup set enough so that whatever it was written with would be 
happy enough to restore the data once pieced back together. A mix of 
tar, and ufsbackup for the most part.

During this process, I bought an Exabyte Mammoth off eBay - didn't use 
it much, but it read those old tapes just fine.

I was able to recover scads of personal stuff that I already had copies 
of, along with a few dumps of the USENET systems I was using to serve as 
a 3-modem BBS for USENET. And yes, sometimes, I go back into old backup 
tapes to recover data I already have on disk. I hate bit-rot, I do 
whatever I can to mitigate it.

art k.

PS: DAT 4mm tape drives, especially whatever Sun was using, were awful. 
Around 50% of them I dealt with all got into a mode within the first 
year where they would accept a tape, and just kick it back out right 
away. Because they were under support, they were just replaced, so I 
never looked into it hardware-wise.



On 11/25/2019 12:07 PM, Al Kossow wrote:
>
> On 11/24/19 7:24 PM, Larry McVoy wrote:
>> So that sounds like a different problem.  People correct me if I'm
>> wrong but the exabyte drives seemed to have a head alignment problem.
> They are 8mm helical-head drives. they wouldn't go out of alignment by
> bumping them, the worse would be the tape would lose tension if you
> smacked the tensioning arms hard enough
>
> They do have a lot of rubber parts inside.
> Rollers crack and belts go soft. I have several dozen dead EX8200s from that.
>
> I have a whole box of 8mm backup tapes that just came in, and a small
> number of working drives. The Linux software I wrote to do 9 track tape recovery
> from a SCSI 9 track drive works just fine on an Exabyte.
>
> And I'm not offering to read Jason's mystery reels.
>
>
>
>
>
>


^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  3:24       ` Larry McVoy
@ 2019-11-25 17:07         ` Al Kossow
  2019-11-25 17:40           ` Arthur Krewat
  2019-11-25 18:29           ` Warner Losh
  0 siblings, 2 replies; 28+ messages in thread
From: Al Kossow @ 2019-11-25 17:07 UTC (permalink / raw)
  To: tuhs



On 11/24/19 7:24 PM, Larry McVoy wrote:
> So that sounds like a different problem.  People correct me if I'm
> wrong but the exabyte drives seemed to have a head alignment problem.

They are 8mm helical-head drives. they wouldn't go out of alignment by
bumping them, the worse would be the tape would lose tension if you
smacked the tensioning arms hard enough

They do have a lot of rubber parts inside.
Rollers crack and belts go soft. I have several dozen dead EX8200s from that.

I have a whole box of 8mm backup tapes that just came in, and a small
number of working drives. The Linux software I wrote to do 9 track tape recovery
from a SCSI 9 track drive works just fine on an Exabyte.

And I'm not offering to read Jason's mystery reels.






^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  3:29       ` Dave Horsfall
@ 2019-11-25  3:36         ` Larry McVoy
  2019-11-25 22:34           ` Dave Horsfall
                             ` (2 more replies)
  0 siblings, 3 replies; 28+ messages in thread
From: Larry McVoy @ 2019-11-25  3:36 UTC (permalink / raw)
  To: Dave Horsfall; +Cc: The Eunuchs Hysterical Society

On Mon, Nov 25, 2019 at 02:29:02PM +1100, Dave Horsfall wrote:
> On Mon, 25 Nov 2019, George Michaelson wrote:
> 
> >I just failed with a Sun DAT drive. Cable and card bought online,
> >recognized by the mt command, but all it does is eject tapes.
> 
> They're worse than 9-track tapes, and that's saying something :-)

Really?  Are we talking about those tapes that looked like reel to reel
audio tapes but bigger?  Like this?

https://www.canajunfinances.com/wp-content/uploads/2013/04/9-Track-Tape.jpg

Because those are 1000x more reliable than an exabyte tape, they just 
worked.  Pretty much no matter what, you can spool up that tape and it
will read.  30 years later it will read.

Exabyte won't read 20 minutes later.

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  1:42     ` George Michaelson
  2019-11-25  3:24       ` Larry McVoy
@ 2019-11-25  3:29       ` Dave Horsfall
  2019-11-25  3:36         ` Larry McVoy
  1 sibling, 1 reply; 28+ messages in thread
From: Dave Horsfall @ 2019-11-25  3:29 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

On Mon, 25 Nov 2019, George Michaelson wrote:

> I just failed with a Sun DAT drive. Cable and card bought online, 
> recognized by the mt command, but all it does is eject tapes.

They're worse than 9-track tapes, and that's saying something :-)

Oh, if you must use one, make sure to use data-quality tapes, not the 
cheaper media.

-- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  1:42     ` George Michaelson
@ 2019-11-25  3:24       ` Larry McVoy
  2019-11-25 17:07         ` Al Kossow
  2019-11-25  3:29       ` Dave Horsfall
  1 sibling, 1 reply; 28+ messages in thread
From: Larry McVoy @ 2019-11-25  3:24 UTC (permalink / raw)
  To: George Michaelson; +Cc: The Eunuchs Hysterical Society

So that sounds like a different problem.  People correct me if I'm
wrong but the exabyte drives seemed to have a head alignment problem.
If you bumped the drive, the head moved and it stayed moved.  So now
it can't read the tape because the head is offset.  I have no data to
support this but I suspect someone that really understood these drives
might be able to move the head back in alignment.


On Mon, Nov 25, 2019 at 11:42:36AM +1000, George Michaelson wrote:
> I just failed with a Sun DAT drive. Cable and card bought online,
> recognized by the mt command, but all it does is eject tapes.
> 
> I am going to get a friend to come play with rubber bands and WD40 but
> I'm not hopeful.
> 
> Bunch of data going to be rotting on tape.
> 
> -G
> 
> On Mon, Nov 25, 2019 at 11:41 AM Dave Horsfall <dave@horsfall.org> wrote:
> >
> > On Sun, 24 Nov 2019, Larry McVoy wrote:
> >
> > > Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out
> > > of building 5 at Sun and into building 9 at SGI and the tapes wouldn't
> > > read back.
> >
> > I've had all sorts of problems with those drives.  Fortunately there was
> > an Exabyte agent not far from us, so they got a lot of our business.
> >
> > -- Dave

-- 
---
Larry McVoy            	     lm at mcvoy.com             http://www.mcvoy.com/lm 

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-25  1:41   ` Dave Horsfall
@ 2019-11-25  1:42     ` George Michaelson
  2019-11-25  3:24       ` Larry McVoy
  2019-11-25  3:29       ` Dave Horsfall
  0 siblings, 2 replies; 28+ messages in thread
From: George Michaelson @ 2019-11-25  1:42 UTC (permalink / raw)
  To: Dave Horsfall; +Cc: The Eunuchs Hysterical Society

I just failed with a Sun DAT drive. Cable and card bought online,
recognized by the mt command, but all it does is eject tapes.

I am going to get a friend to come play with rubber bands and WD40 but
I'm not hopeful.

Bunch of data going to be rotting on tape.

-G

On Mon, Nov 25, 2019 at 11:41 AM Dave Horsfall <dave@horsfall.org> wrote:
>
> On Sun, 24 Nov 2019, Larry McVoy wrote:
>
> > Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out
> > of building 5 at Sun and into building 9 at SGI and the tapes wouldn't
> > read back.
>
> I've had all sorts of problems with those drives.  Fortunately there was
> an Exabyte agent not far from us, so they got a lot of our business.
>
> -- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:52 ` Larry McVoy
  2019-11-24 22:58   ` Rico Pajarola
@ 2019-11-25  1:41   ` Dave Horsfall
  2019-11-25  1:42     ` George Michaelson
  2019-11-27 19:31   ` John Foust
  2 siblings, 1 reply; 28+ messages in thread
From: Dave Horsfall @ 2019-11-25  1:41 UTC (permalink / raw)
  To: The Eunuchs Hysterical Society

On Sun, 24 Nov 2019, Larry McVoy wrote:

> Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out 
> of building 5 at Sun and into building 9 at SGI and the tapes wouldn't 
> read back.

I've had all sorts of problems with those drives.  Fortunately there was 
an Exabyte agent not far from us, so they got a lot of our business.

-- Dave

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:58   ` Rico Pajarola
@ 2019-11-24 23:45     ` Clem Cole
  0 siblings, 0 replies; 28+ messages in thread
From: Clem Cole @ 2019-11-24 23:45 UTC (permalink / raw)
  To: Rico Pajarola; +Cc: TUHS main list

[-- Attachment #1: Type: text/plain, Size: 856 bytes --]

I have two and they have found them to be spotting years later.  I have
them in an FreeBSD box with SCSI.

On Sun, Nov 24, 2019 at 5:59 PM Rico Pajarola <rp@servium.ch> wrote:

>
>
> On Sun, Nov 24, 2019 at 2:53 PM Larry McVoy <lm@mcvoy.com> wrote:
>
>> Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of
>> building 5 at Sun and into building 9 at SGI and the tapes wouldn't read
>> back.
>>
> We called them buffered dev-nulls.
>
> TBH, that's what we called most tapes except for DLTs.
>
>
>
>> On Sun, Nov 24, 2019 at 05:39:30PM -0500, Richard Salz wrote:
>> > Historically important he says. The guy had creds.
>> > https://twitter.com/textfiles/status/1198706617967095809?s=19
>>
>> --
>> ---
>> Larry McVoy                  lm at mcvoy.com
>> http://www.mcvoy.com/lm
>>
> --
Sent from a handheld expect more typos than usual

[-- Attachment #2: Type: text/html, Size: 2069 bytes --]

<div><div dir="auto">I have two and they have found them to be spotting years later.  I have them in an FreeBSD box with SCSI. </div></div><div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Nov 24, 2019 at 5:59 PM Rico Pajarola &lt;<a href="mailto:rp@servium.ch">rp@servium.ch</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Nov 24, 2019 at 2:53 PM Larry McVoy &lt;<a href="mailto:lm@mcvoy.com" target="_blank">lm@mcvoy.com</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of<br>
building 5 at Sun and into building 9 at SGI and the tapes wouldn&#39;t read<br>
back.<br></blockquote><div>We called them buffered dev-nulls.</div><div><br></div><div>TBH, that&#39;s what we called most tapes except for DLTs.</div></div></div><div dir="ltr"><div class="gmail_quote"><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
On Sun, Nov 24, 2019 at 05:39:30PM -0500, Richard Salz wrote:<br>
&gt; Historically important he says. The guy had creds.<br>
&gt; <a href="https://twitter.com/textfiles/status/1198706617967095809?s=19" rel="noreferrer" target="_blank">https://twitter.com/textfiles/status/1198706617967095809?s=19</a><br>
<br>
-- <br>
---<br>
Larry McVoy                  lm at <a href="http://mcvoy.com" rel="noreferrer" target="_blank">mcvoy.com</a>             <a href="http://www.mcvoy.com/lm" rel="noreferrer" target="_blank">http://www.mcvoy.com/lm</a> <br>
</blockquote></div></div>
</blockquote></div></div>-- <br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature">Sent from a handheld expect more typos than usual</div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:52 ` Larry McVoy
@ 2019-11-24 22:58   ` Rico Pajarola
  2019-11-24 23:45     ` Clem Cole
  2019-11-25  1:41   ` Dave Horsfall
  2019-11-27 19:31   ` John Foust
  2 siblings, 1 reply; 28+ messages in thread
From: Rico Pajarola @ 2019-11-24 22:58 UTC (permalink / raw)
  To: Larry McVoy; +Cc: TUHS main list

[-- Attachment #1: Type: text/plain, Size: 596 bytes --]

On Sun, Nov 24, 2019 at 2:53 PM Larry McVoy <lm@mcvoy.com> wrote:

> Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of
> building 5 at Sun and into building 9 at SGI and the tapes wouldn't read
> back.
>
We called them buffered dev-nulls.

TBH, that's what we called most tapes except for DLTs.



> On Sun, Nov 24, 2019 at 05:39:30PM -0500, Richard Salz wrote:
> > Historically important he says. The guy had creds.
> > https://twitter.com/textfiles/status/1198706617967095809?s=19
>
> --
> ---
> Larry McVoy                  lm at mcvoy.com
> http://www.mcvoy.com/lm
>

[-- Attachment #2: Type: text/html, Size: 1410 bytes --]

<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Nov 24, 2019 at 2:53 PM Larry McVoy &lt;<a href="mailto:lm@mcvoy.com">lm@mcvoy.com</a>&gt; wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of<br>
building 5 at Sun and into building 9 at SGI and the tapes wouldn&#39;t read<br>
back.<br></blockquote><div>We called them buffered dev-nulls.</div><div><br></div><div>TBH, that&#39;s what we called most tapes except for DLTs.</div><div><br></div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
On Sun, Nov 24, 2019 at 05:39:30PM -0500, Richard Salz wrote:<br>
&gt; Historically important he says. The guy had creds.<br>
&gt; <a href="https://twitter.com/textfiles/status/1198706617967095809?s=19" rel="noreferrer" target="_blank">https://twitter.com/textfiles/status/1198706617967095809?s=19</a><br>
<br>
-- <br>
---<br>
Larry McVoy                  lm at <a href="http://mcvoy.com" rel="noreferrer" target="_blank">mcvoy.com</a>             <a href="http://www.mcvoy.com/lm" rel="noreferrer" target="_blank">http://www.mcvoy.com/lm</a> <br>
</blockquote></div></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:39 Richard Salz
  2019-11-24 22:50 ` Jim Capp
@ 2019-11-24 22:52 ` Larry McVoy
  2019-11-24 22:58   ` Rico Pajarola
                     ` (2 more replies)
  1 sibling, 3 replies; 28+ messages in thread
From: Larry McVoy @ 2019-11-24 22:52 UTC (permalink / raw)
  To: Richard Salz; +Cc: TUHS main list

Good luck with that.  I had a 4/470 that had an exabyte, wheeled it out of
building 5 at Sun and into building 9 at SGI and the tapes wouldn't read
back.

On Sun, Nov 24, 2019 at 05:39:30PM -0500, Richard Salz wrote:
> Historically important he says. The guy had creds.
> https://twitter.com/textfiles/status/1198706617967095809?s=19

-- 
---
Larry McVoy            	     lm at mcvoy.com             http://www.mcvoy.com/lm 

^ permalink raw reply	[flat|nested] 28+ messages in thread

* Re: [TUHS] Someone wants to use an exabyte
  2019-11-24 22:39 Richard Salz
@ 2019-11-24 22:50 ` Jim Capp
  2019-11-24 22:52 ` Larry McVoy
  1 sibling, 0 replies; 28+ messages in thread
From: Jim Capp @ 2019-11-24 22:50 UTC (permalink / raw)
  To: Richard Salz; +Cc: TUHS main list

[-- Attachment #1: Type: text/plain, Size: 431 bytes --]

I still have an exabyte scsi drive. You can read it with Linux. You just need a suitable SCSI card. tar/cpio all work as expected. 


From: "Richard Salz" <rich.salz@gmail.com> 
To: "TUHS main list" <tuhs@minnie.tuhs.org> 
Sent: Sunday, November 24, 2019 5:39:30 PM 
Subject: [TUHS] Someone wants to use an exabyte 


Historically important he says. The guy had creds. https://twitter.com/textfiles/status/1198706617967095809?s=19 

[-- Attachment #2: Type: text/html, Size: 822 bytes --]

<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Times New Roman; font-size: 12pt; color: #000000'>I still have an exabyte scsi drive.&nbsp; You can read it with Linux.&nbsp; You just need a suitable SCSI card.&nbsp; tar/cpio all work as expected.&nbsp;&nbsp;<br><br><hr id="zwchr"><b>From: </b>"Richard Salz" &lt;rich.salz@gmail.com&gt;<br><b>To: </b>"TUHS main list" &lt;tuhs@minnie.tuhs.org&gt;<br><b>Sent: </b>Sunday, November 24, 2019 5:39:30 PM<br><b>Subject: </b>[TUHS] Someone wants to use an exabyte<br><br><div dir="auto">Historically important he says. The guy had creds.&nbsp;&nbsp;<a href="https://twitter.com/textfiles/status/1198706617967095809?s=19" target="_blank">https://twitter.com/textfiles/status/1198706617967095809?s=19</a></div>
</div></body></html>

^ permalink raw reply	[flat|nested] 28+ messages in thread

* [TUHS] Someone wants to use an exabyte
@ 2019-11-24 22:39 Richard Salz
  2019-11-24 22:50 ` Jim Capp
  2019-11-24 22:52 ` Larry McVoy
  0 siblings, 2 replies; 28+ messages in thread
From: Richard Salz @ 2019-11-24 22:39 UTC (permalink / raw)
  To: TUHS main list

[-- Attachment #1: Type: text/plain, Size: 113 bytes --]

Historically important he says. The guy had creds.
https://twitter.com/textfiles/status/1198706617967095809?s=19

[-- Attachment #2: Type: text/html, Size: 215 bytes --]

<div dir="auto">Historically important he says. The guy had creds.  <a href="https://twitter.com/textfiles/status/1198706617967095809?s=19">https://twitter.com/textfiles/status/1198706617967095809?s=19</a></div>

^ permalink raw reply	[flat|nested] 28+ messages in thread

end of thread, back to index

Thread overview: 28+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-11-25 18:12 [TUHS] Someone wants to use an exabyte Norman Wilson
  -- strict thread matches above, loose matches on Subject: below --
2019-11-24 22:39 Richard Salz
2019-11-24 22:50 ` Jim Capp
2019-11-24 22:52 ` Larry McVoy
2019-11-24 22:58   ` Rico Pajarola
2019-11-24 23:45     ` Clem Cole
2019-11-25  1:41   ` Dave Horsfall
2019-11-25  1:42     ` George Michaelson
2019-11-25  3:24       ` Larry McVoy
2019-11-25 17:07         ` Al Kossow
2019-11-25 17:40           ` Arthur Krewat
2019-11-25 17:45             ` Larry McVoy
2019-11-25 17:49               ` Jon Steinhart
2019-11-25 18:34               ` Arthur Krewat
2019-11-25 21:08                 ` John P. Linderman
2019-11-25 21:11                   ` ron
2019-11-25 21:30                     ` John P. Linderman
2019-11-25 21:38               ` Dave Horsfall
2019-11-25 18:29           ` Warner Losh
2019-11-25  3:29       ` Dave Horsfall
2019-11-25  3:36         ` Larry McVoy
2019-11-25 22:34           ` Dave Horsfall
2019-11-26  1:38             ` Lawrence Stewart
2019-11-25 22:46           ` Dennis Boone
2019-11-25 22:57           ` Henry Bent
2019-11-27 19:31   ` John Foust
2019-11-27 20:56     ` Arthur Krewat
2019-11-27 21:25       ` Dave Horsfall

The Unix Heritage Society mailing list

Archives are clonable: git clone --mirror http://inbox.vuxu.org/tuhs

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://inbox.vuxu.org/vuxu.archive.tuhs


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git