Sorry folks - I should have sent this out weeks ago. Life got on top
of me....:)
Original question: Is there a 256MB limit for installing DEC Unix 4.0D ?
This is the authoratitive answer from Dr Tom Blinn of DEC:
[snip]
There is a bug in the AlphaPC 164/LX console firmware that panics the system
or hangs it (the details differ from instance to instance) when you attempt
to call back into the console firmware to save the environment variables to
reboot the system.
This bug is observed on systems with more than 256MB memory, and not with
less.
So, when you boot the system initially to install, you need to specify the
flag "i" (for an interactive boot), and when you are prompted for the name
of the kernel to be booted, you enter
vmunix memlimit=256
and then the system will not use more than 256MB memory. You do the install
and everything will be fine. Once the system is up and running, you can
then power cycle to force the console to resize memory, and once you've done
that you will be running with the full memory (512MB, 1GB, whatever).
There are a couple of commands in DIGITAL UNIX that can exercise the bug in
the console firmware.
One is the flavor of sysconfig that modifies the "bparm" subsystem
parameters (boot_osflags, bootdef_dev, boot_dev), and another is the new
consvar command if you use the "-a" flag to set the variables in non-
volatile memory.
This is NOT a DIGITAL UNIX restriction, and once you're past installation,
if you avoid using the commands that attempt to modify the console firmware
environment variables (which all require root privilege), you'll be fine.
I am running DIGITAL UNIX V4.0D on an AlphaPC 164/LX with 1GB of memory, and
I have no problems. I'm working with the responsible firmware engineer to
try to pin down why the console firmware is failing. We don't know yet. We
know it's the firmware, and we know what it's doing, but we don't know why
it is failing.
I hope this helps clarify things. There are really only maybe one or two
folks in the whole world who really understand the status of this, and I am
one of them. If you want a system with more than 256MB memory, and you are
considering buying it from Aspen, go for it, it's a great system, and they
are a good company to buy from. We will find and fix the bug eventually; in
the meantime, you can readily work around it for installation, and then just
don't do the things that will hang the system.
Tom
Dr. Thomas P. Blinn, UNIX Software Group, Digital Equipment Corporation
[snip]
--
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|Dave Bowler |
|Physics Department d.bowler_at_keele.ac.uk |
|Keele University Tel:(01782) 584140 |
|Keele Fax:(01782) 711093 |
|Staffordshire ST5 5BG |
| http://www.keele.ac.uk/depts/ph/tc/dave/home.html |
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Received on Tue May 05 1998 - 10:12:18 NZST