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<p>Gee wiz, that stinks. Lose anything? Any chance of recovery?
(I'm not familiar with the RD53). No matter how long it takes, we
always seem to learn, 'do regular backups' the (unexpected) hard
way. Two anecdotes (from actual experience):</p>
<ul>
<li>A crashed disk will always take down at least two or more disk
drives and at least one other disk because it will be put into a
working drive to determine if it or the original drive has
failed, this crashes the head assembly on the 'test' drive which
then ruins the working media that had been taken out.</li>
<li>Unless both performed regularly <u>and</u> verified
regularly, backups, won't.</li>
<li>A tape drive will always break just before signs of disk
failure. This is why you must have two tape drives.<br>
</li>
</ul>
<div class="moz-cite-prefix">I was in the machine room one day
assisting our systems assurance folks in banging down some lines
for another DH11 (we were getting some 'ringing' at higher
speeds). I happened to notice that one of our TU45's was doing a
'strange' amount of rewrites on a particular tape. Closer
inspection revealed that it was the previous evening's incremental
backup. Started (automatically) at 2:00 AM, it still hadn't
finished by Noon, more than twice the usual time.</div>
<div class="moz-cite-prefix">
<p>I first thought to abort and re-queue the backup and give the
drive a good cleaning (and maybe a chance to catch its breath).
Once I had done the re-queue, I looked at the tape and noticed
it was over 4 years old and seen regular bi-weekly service for
all that time. A TU55 DECtape will laugh at that kind of usage;
they used to test the redundancy logic by un-spooling them and
driving a car over the media. Not so 1600 BPI magtape.</p>
<p>That day, we started rotating all our backup tapes out for new
ones. That took about two months (12 tapes for daily bi-weekly
incrementals, 30 for bi-weekly full and another 30 for
bi-monthly fulls). I kept wondering what was going to break
before we finished the rotation, but incredibly, nothing did.
It must have known I was watching...</p>
<p>To this day, the 20's have quarterly batch backup, one backs up
to another. Other systems backup to OneDrive.<br>
</p>
</div>
<blockquote type="cite"
cite="mid:D0C892CB-CE47-43A0-A15E-8C8E2683263A@avanthar.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<hr width="100%" size="2">On 3/7/20 11:26 AM, Zane Healy wrote:
<div><br class="">
<blockquote type="cite" class="">
<div class="">On Mar 7, 2020, at 7:44 AM, Robert Armstrong
<<a href="mailto:bob@jfcl.com" class=""
moz-do-not-send="true">bob@jfcl.com</a>> wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
<div class="WordSection1" style="page: WordSection1;
caret-color: rgb(0, 0, 0); font-family: Helvetica;
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<div style="margin: 0in 0in 0.0001pt; font-size: 11pt;
font-family: Calibri, sans-serif;" class=""><span
style="color: rgb(31, 73, 125);" class=""> For older
VAXes there is always the option of running VMS v4.x,
which is pre-LMF. I know VMS4 supported the
MicroVAX-II; can’t remember if it ever supported the
MicroVAX-III. Somebody will have to dig up an SPD for
VMS 4.7.<o:p class=""></o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt;
font-family: Calibri, sans-serif;" class=""><span
style="color: rgb(31, 73, 125);" class=""><o:p
class=""> </o:p></span></div>
<div style="margin: 0in 0in 0.0001pt; font-size: 11pt;
font-family: Calibri, sans-serif;" class=""><span
style="color: rgb(31, 73, 125);" class="">Bob</span></div>
</div>
</div>
</blockquote>
</div>
<br class="">
<div class="">VAX/VMS 4.x runs on the MicroVAX-III. I booted it
once on my KA-650, when I got it. Then when I went to back it
up, the RD53 died.</div>
<div class=""><br class="">
</div>
<div class="">Zane</div>
</blockquote>
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