robespierre wrote:
Diskless workstations were an early form of thin client. The idea is that system administration and backup only need to be done for the server, and all the clients are "zero state" so require no management. In practice, they were less cost effective, because all the I/O needed to go through a very slow shared network.
I'd say this view is more in line for the 1990s than the 1980s, when diskless workstations first appeared - when
Apollo DN300s
and
Sun-2s and -3s
were the new hotness. The original impetus for diskless workstations was largely the expense and performance of mass storage. A typical diskless client from that era would be running an almost-complete operating system image, not a cut-down GUI or front-end like a thin client.
What did the mass storage landscape look like, to cause this? In the early 80s you're looking at top-of-the-line hard drives of a few hundred megabytes, using 14" platters and interconnects like SMD, and weighing hundreds of pounds. An example common by the mid-80s would be the
Fujitsu Eagle
, a ~470MB SMD drive using 10.5" platters that would retail for $10,000. Meanwhile in 1985 Seagate announced the ST4051, a 40MB 5.25" HDD which would initially cost you almost $1,000 in OEM quantities, let alone retail, and provide such slow access times and throughput that the same workstation running diskless could often out-perform it despite having all disk I/O go over 10Mb Ethernet to a fast server with an Eagle. Larger 5.25" HDD were available, and their prices did drop rapidly in the latter half of the 80s, but it took a while for the performance equation to change.
So when buying a lab or department of workstations that were going to need a fileserver anyway, why spend $1,500-2,000 extra per machine for poor performance and little space when you could run them diskless and get a second big shared drive on the server? In 1986 such a server package (Sun-2/170, two Eagles, and a tape drive) would list for $80,000, versus $8,900 for a Sun-2/50 desktop w/o disk. The December 198
8
add-on cost for an external "shoebox" with 71MB drive suitable for the Sun-2/50 was nearly $3,000 list...
It was common in the 90s to recycle those same older workstations as Xterminals. There were even packages like "xkernel" to help do this - actually, upon Googling, it looks like there may have been a few variants. See
http://www.bond.id.au/~gnb/papers/xkernel.ps.Z
for a nice overview that could be adapted to any number of systems - including DECstations running Ultrix.
Anyway depending on the dates involved, using the DECstations as Xterminals was probably a decent way to avoid the expense of buying new Xterminals, and it would be straightforward to have them run a stripped down Ultrix diskless config with an X server. And as robespierre said, allow XDMCP to manage it from a (then) big, fast Alpha. And given what CPUs were being used in low-end Xterminals, you were probably getting better performance to boot.
...
Now?
-
+MLA
...
Other:
DEC
Sun
,
DG AViiON
,
NeXT
Reminds me of setting up X11 builds to run over the weekend back in '89-91...
