Re: UX400S: a decent machine

["Donald H. Mitchell" <dmitchell%backus.trc.amoco.com@RELAY.CS.NET>]

    Date: Fri, 19 Jan 90 12:42:16 EST
    From: bouma@cs.purdue.edu


	 It's fast:  as fast or at least close to as fast as the XL--certainly
       a lot faster than the MacIvory because it only uses the host's buss for
       SCSI and network requests.  All memory is directly accessed on its own
       buss.

    Excuse my hardware ignorance, please. Does this mean it has its own
    on-board memory?  If so, how much memory can you put on it and howdoes 
    that reflect in its cost? What is SCSI?

Yes, the board can hold 4MWords.  You can also purchase an additional
memory board capable of holding another 4MWords.  When you get the extra
board, you get a special cable connecting the boards to bypass the VME
bus.  The basic system has 2MWords (which I'm using).  More memory is
additional money.

SCSI is an industry standard interface for devices especially disk
drives, tape drives, etc.

       Some of the initial tie-ups were Sun host compatibility.  Sure,
       Symbolics chose the weird path of only authorizing file servers as
       hosts.  But I have mine working well in a 4/110.  You certainly won't

    Why does it have to be a file server? Doesn't file server just mean
    that the machine has exported (NFS) its disks? What affect could that
    have on the UX400?

Technically you're correct; however, Sun calls these machines "File
Servers" because they, by default, come with high-capacity disks and
most people who buy more than one Sun don't buy only these "File
Servers".


       Many products come built in: NFS, TCP/IP, and X.  These all work
       substantially better than their counterparts in 7.2.

    Do you mean these things are on the board in ROM? How exactly do you
    go about booting the thing up with a clean environment? Where are the
    boot files stored?

Built into the distribution system.  
You'll have to get the installation manual to confirm everything.  It
does not include these products in ROM.  In my current
configuration, my boot files are on a disk on the SCSI port under a
Unix-controlled file that is the whole FEP file system for the UX.  A
Unix program initializes the board and informs it where its FEP
files are located.  When you boot the UX, it loads whatever FEP files you
tell it and then like all Symbolics' hosts figures out who it is etc.

What may confuse people is that the UX could be in a Unix fileserver
that doesn't even have a graphics terminal.  Whenever the Unix system
boots, it starts the board's services but does not bring up the FEP or
Genera windows.  A user on any Sun that has a graphics terminal
with X merely types in the Unix command:

Genera UXboard-name

where UXboard-name is the Symbolic's host name (not the Sun that it is
embedded in, the board itself).  I don't know the technical details but
somehow the Genera program causes a new X window to appear that talks
directly to the Symbolics's FEP.  The user then types, "hello" and
"boot" and up comes another X window containing the genera interface.
Note, the Sun that contains the board does nothing during any of this
except share its Ethernet port.  BTW: if the UX was already booted, when
you invoke the Unix "Genera" command, both the FEP cold load and Genera
X windows will come up with the last state (i.e., you don't have to boot
every time you start a session).  Note also that although the Sun and
Symbolics share the port, they have distinct addresses with no
interference.