yang1@ntvax.UUCP (cqyang class) (06/07/89)
I understood that the 3B20D also could be used as a general purpose minicomputer, and there are not many machines I know of (execpt Tandems) that would allow board replacements while the machine is running. I was also interested if anyone had made use of the writtable instruction set. ******************************************************************************* * "It is most gratifying that your enthusiasm for * * Jim Stinson our planet continues unabated and so we would * * University of North Texas like to assure you that the guided missiles * * yang1@dept.csci.unt.edu currently converging on your ship are part of a * * special service we extend to all of our most * * Warning to the enthusiastic clients, and the fully armed * * 'Heart of Gold' crew, nuclear warheads are of course merely a courtesy * * "The Hitchhiker's Guide detail. We look forward to your custom in future * * to the Galaxy" lives. Thank you." * *******************************************************************************
mlewis@unocss.UUCP (Marcus S. Lewis) (06/09/89)
In article <486@ntvax.UUCP>, yang1@ntvax.UUCP (cqyang class) writes: > > > I understood that the 3B20D also could be used as a general purpose > minicomputer, and there are not many machines I know of (execpt Tandems) > that would allow board replacements while the machine is running. This is NOT a commercial - I don't work for Data General, and soon will not be working with DG equipment. One of the main features of the new MV/40000HA machine just now shipping is that the FEs can pull a board out of the box without too much hassle, and without shutting down the machine. The HA stands for High Availability. My boss wants one, I want one - can't have one. My understanding (also from a DG FE) was that the difference between a mini and a mainframe was that on a mainframe you can to diagnostics and swapout maintenance without shutting down. What enables the MV/40 to do this is a new bus (new to the MV series) controller. Marc Lewis -- Na khuya mne podpis'? | Internet: cs057@zeus.unl.edu | UUCP: uunet!btni!unocss!mlewis Go for it! | Bitnet: CS057@UNOMA1 ---------------------------------------------------------------------------
bga@raspail.cdcnet.cdc.com (Bruce Albrecht) (06/12/89)
In article <822@unocss.UUCP>, mlewis@unocss.UUCP (Marcus S. Lewis) writes: > My understanding (also from a DG FE) was that the difference between a mini > and a mainframe was that on a mainframe you can to diagnostics and swapout > maintenance without shutting down. What enables the MV/40 to do this is a > new bus (new to the MV series) controller. I think your DG FE was putting you on. There's nothing inherent in a mainframe that allows it to do online diagnostics, etc., that is peculiar to a mainframe. If the software and hardware is designed to allow for it, you can logically turn almost anything off, and pull it. Of course, outside of a few machines specifically designed for fault-tolerance, losing a CPU is fatal.
jps@cbnewsd.ATT.COM (j.p.schoonover) (06/16/89)
In article <486@ntvax.UUCP>, yang1@ntvax.UUCP (cqyang class) writes: > > > I understood that the 3B20D also could be used as a general purpose > minicomputer, and there are not many machines I know of (execpt Tandems) > that would allow board replacements while the machine is running. I was > also interested if anyone had made use of the writtable instruction set. I don't know that AT&T has tried to sell the 3B20D as a general purpose mini, but I wouldn't recommend using it that way. It's too old a machine. A project using the 3B20D called TSPS did use the ability to write micro-code for this machine to emulate the 1A processor. J. P. Schoonover (312) 979-7907 iwtds!jps (A 3B20D field support kind of guy)
gld@CUNIXD.CC.COLUMBIA.EDU (Gary L Dare) (06/17/89)
In article <226@cbnewsd.ATT.COM> J. P. Schoonover wrote: > >I don't know that AT&T has tried to sell the 3B20D as a general purpose >mini, but I wouldn't recommend using it that way. It's too old a machine. I don't know if AT&T tried to *market* them as such, but they have been donating these machines to various universities including Columbia. We received three, but they were decommissioned after two years because their service contracts were *prohibitive* and the System V OS version was an old, beta - couldn't afford new code, hard to find a system manager full-time, no NFS so we could use them as communications hubs (I was very enthusiastic about them, as you can tell). A shame. I don't know how many of the recipients have their systems running and happy. Is anyone out there part of the 3B20 user group, U3G?? gld -- ~~~~~~~~~~~~~~~~~~~~~~~~ je me souviens ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Gary L. Dare > gld@eevlsi.ee.columbia.EDU "Roll Over Khomeini - > gld@cunixd.cc.columbia.EDU and tell Pahlavi the news!" > gld@cunixc.BITNET
jps@cbnewsd.ATT.COM (j.p.schoonover) (07/22/89)
In article <8906161850.AA19350@cunixd.cc.columbia.edu>, gld@CUNIXD.CC.COLUMBIA.EDU (Gary L Dare) writes: > In article <226@cbnewsd.ATT.COM> J. P. Schoonover wrote: > > > >I don't know that AT&T has tried to sell the 3B20D as a general purpose > >mini, but I wouldn't recommend using it that way. It's too old a machine. > > I don't know if AT&T tried to *market* them as such, but they have been > donating these machines to various universities including Columbia. We > received three, but they were decommissioned after two years because > their service contracts were *prohibitive* and the System V OS version > was an old, beta - couldn't afford new code, hard to find a system > manager full-time, no NFS so we could use them as communications hubs > (I was very enthusiastic about them, as you can tell). A shame. > > I don't know how many of the recipients have their systems running and > happy. Is anyone out there part of the 3B20 user group, U3G?? > > Gary L. Dare > gld@eevlsi.ee.columbia.EDU Gary, what you had were 3B20S machines, not 3B20D machines. The 'S' stands for Simplex and the 'D' stands for Duplex. The Simplex was indeed sold as a general purpose machine. In fact, we still use them on the project I work on and SVR3 is available (with RFS) for the Simplex, but the Duplex is only used in switching systems as a fault tolerant processor. The name Duplex comes from the duplication of main memory and the CU. You cannot run both CU's at the same time. The two CU's and memory are duplicated so that when trouble is detected in one, the machine will automatically switch to the other. Also, there is no way to "upgrade" a simplex to a duplex. J. P. Schoonover (312) 979-7907 iwtds!jps