name resolution

[Gene Heskett]

On Sunday 26 November 2017 00:18:09 Ken D'Ambrosio wrote:

> >> IPX was a disaster at scale.  The fact that everything was routed
> >> by the
> >> unique card address (the name of which escapes me, but it was akin
> >> to an
> >> Ethernet card's MAC) meant that each router had to know where
> >> *every device
> >> on every segment* was.  The routing tables went through the roof,
> >> fast.
> >
> > I have to admit, I never ran very large IPX networks. My boss built
> > a 4/5 floor 300+ station one, with an actual _thick_ Ethernet
> > backbone and mirrored servers under Netware 3 SFT. I  was too junior
> > to be allowed near that, back then!
>
> I was just earning my spurs back then, but worked at both UPS's IS HQ
> and JP Morgan on Wall St., and both were running Netware over Token
> Ring/IPX.  (As well as SNA/SAA uplinks to the mainframes.)  And at JP
> Morgan, doing remote host lookups was like watching paint dry.
>
> > Oh gods, yes. In fact I am working on a demo DR-DOS VM image right
> > now, and fighting such issues all over again. It's kinda fun
> > resurrecting knowledge dead and unused for 20+ years, but also a
> > pain -- like troubleshooting SCSI bus issues, when I was
> > refurbishing my vintage Mac collection for sale before leaving the
> > UK in 2013/2014.
>
> OK.  I loved DR-DOS, but I'm not sure I'm masochistic enough to want
> to fire up a VM to re-experience the pain.  (I say this as someone
> with a Sun, a NeXT, an IMSAI 8080, and two Amigas in my basement.)
>
> > Joking about dancing widdershins under a fool moon while sacrificing
> > a _black_ chicken (white only if it's fast wide SCSI-2) ... and if
> > you have isolated everything and know that the IRQ, DMA, I/O port,
> > cabling and termination is fine, then it's the termination. Once
> > you've fixed that, there's only one place to look... it's the
> > termination.
>
And after you'd fixed that again , it was still the termination. 99% of 
all the termination problems with scsi is that the designers of the 
interface cards specced a schotkey diode for the powerline isolation 
diode, but the fscking bean counters changed it for a std si diode on 
the way to the production floor because it was $3 cheaper, with its .7 
volts voltage drop across it, which in turn reduced the logic one noise 
margin to zip, so the bus errors were at least once per write. One 
company that makes cards for the amiga even drew up the artwork for 
resistive terms bass ackwards, so in addition to putting a schotkey 
diode in it, I had to cut the traces and reverse the 5 volt and grounded 
ends of all 3 of its soldered in terminators. That card never again had 
a bus error that wasn't a fading psu. The termination was finally fixed. 
Logic one resting voltage was finally at 3.3 volts, the design target 
for a scsi bus. But watch for fading psu's, long before the logic or 
anything else complained because the 5 volts was down to 4.7, screwing 
the logic one noise margin, the buss errors were raising their heads 
again.

But that was the 2nd time in my life as a journeyman C.E.T., which I  am, 
that I called the maker and gave him hell, telling him the best part 
must have run down his mothers leg. Totally unrelated but important in a 
production room for a tv station where we had quite a few amiga's doing 
video work, and several of the A4000's had 68060 cards in them, I found 
that some production people at Commode Door had installed all the 6.3 
volt electrolytic bypass caps backwards on that $1500 card. Took about a 
year before they started blowing out the tops. With the soldering tools 
of the day, fixing that wasn't my idea of fun. But by then there wasn't 
anybody answering the phone at Commode Door.

Just before I retired in 2002 as the CE there at that tv station, we 
bought some Apple G5's to replace the failing amiga's, but they should 
have come with fire extinguishers. None of them lasted 6 months.

> I loved SATA because it let us standardize on laptop HD connectors. 
> But I *really* loved it because SCSI -- which I loved back in the 80's
> -- I'd come to loathe by the mid-90's: 47 different freaking
> connectors, and then terminators were active, passive, or some weird
> thing in the middle.  Just made me shake my head in confusion, and
> HATE having to try to track down the right stuff.

Which, if dealing with a sata thats flooding the syslog with bus and 
drive resets, and the sata cables are that pretty hot red color, replace 
them with ANY other color of cable, that plastic dye converts the copper 
its in contact with into powdered copper oxide. Very poor conductor. 
That plastic dye was known to be a problem by the early 1970's as cable 
production moved to the J.A.Pan company, but all the cable makers could 
see was a booming business selling replacement cables as it was always 
the red wire that failed. See it, replace it with any other color.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>