[comp.sys.ibm.pc] Unix on a 286

minar@reed.bitnet (Nelson Minar,(???)) (02/04/90)

(forgive me if this has been asked before)

what are the options for running Unix on a 286 box, with 640k? Hard drive
space isn't too big of a problem, but I'd like to have both MS-DOS and Unix
on the same physical drive.

alien@cpoint.UUCP (Alien Wells) (02/05/90)

In article <14054@reed.UUCP> minar@reed.bitnet (Nelson Minar) writes:
>what are the options for running Unix on a 286 box, with 640k? Hard drive
>space isn't too big of a problem, but I'd like to have both MS-DOS and Unix
>on the same physical drive.

Real Unixs will not run on a 286 (for quite a few reasons ...).  Real Unixs
also won't run in 640k.  The one I am using requires a 386 and (I believe)
4MB of memory (I have 8MB, which is much more reasonable).  You also need
at least about 100MB hard disk (plus whatever you want for DOS).

The best you will be able to do is to use one of the 'baby Unixs' like Xenix,
but even then I think you are looking at a memory upgrade ...
-- 
--------|	I don't get my eyebrows trimmed, only styled.
Alien   |	  	 		- a Clearpoint VP
--------|     jjmhome!cpoint!alien      bu-cs!mirror!frog!cpoint!alien

sipples@husc8.HARVARD.EDU (Timothy Sipples) (02/05/90)

In article <3877@cpoint.UUCP> alien@cpoint.UUCP (Alien Wells) writes:
>In article <14054@reed.UUCP> minar@reed.bitnet (Nelson Minar) writes:
>>what are the options for running Unix on a 286 box, with 640k? Hard drive
>>space isn't too big of a problem, but I'd like to have both MS-DOS and Unix
>>on the same physical drive.
>Real Unixs will not run on a 286 (for quite a few reasons ...).  Real Unixs
>also won't run in 640k.  The one I am using requires a 386 and (I believe)
>4MB of memory (I have 8MB, which is much more reasonable).  You also need
>at least about 100MB hard disk (plus whatever you want for DOS).

Microport Unix (System V Release 2, I believe) runs on a 286 in as little
as 512K.  (Although more is _quite_ helpful.)  Microport has filed for
Chapter 11, I believe, but they did have a genuine Unix.  (SVR2 may not
be "real" to some people, though.  :-))

Timothy F. Sipples		sipples@husc8.{harvard.edu|bitnet}

davidsen@sixhub.UUCP (Wm E. Davidsen Jr) (02/06/90)

In article <14054@reed.UUCP> minar@reed.bitnet (Nelson Minar) writes:

| what are the options for running Unix on a 286 box, with 640k? Hard drive
| space isn't too big of a problem, but I'd like to have both MS-DOS and Unix
| on the same physical drive.

I have used the following on multiple machines with acceptable
reliability:

  Xenix: available, supported, SysV kernel calls
  PC/ix: might find a copy around, not supported, SysIII

I have used the following on two machines with serious problems:
  Microport V/AT: bankrupt vendor, V.2, serial and two drive problems

I have seen the following and am told it is reliable:
  Venturcom Venix: what I saw was V7/SysIII/V.2 mix

I would buy a 386 M.B. and some real cheap UNIX (maybe ESIX) instead.
-- 
	bill davidsen - sysop *IX BBS and Public Access UNIX
davidsen@sixhub.uucp		...!uunet!crdgw1!sixhub!davidsen

"Getting old is bad, but it beats the hell out of the alternative" -anon

leech@homer.cs.unc.edu (Jonathan Leech) (02/06/90)

In article <3877@cpoint.UUCP> alien@cpoint.UUCP (Alien Wells) writes:
>Real Unixs will not run on a 286 (for quite a few reasons ...).

    This may come as a surprise to you, but "Real Unix" and "Bloated
Monstrosity" are not synonymous.  An IBM AT is far from my favorite
machine, but it runs Xenix, aka System III/V, just fine.  There are
good non-religious reasons to use a 386 instead, such as a wider data
bus, flat address space, and faster CPU, but that's not the point.

>Real Unixs also won't run in 640k.

    Wrong. It does swap a lot if you run large programs.  Performance
improved with 2M more memory.
--
    Jon Leech (leech@cs.unc.edu)    __@/
"We were driving along, minding our own business, when there was a
 sudden flash of blue light which blotted out the stars. I thought it
 was a nuclear bomb going off and despaired for my career." - Keith Hughes

kjeld@iesd.auc.dk (Kjeld Flarup) (02/06/90)

In article <3877@cpoint.UUCP> alien@cpoint.UUCP (Alien Wells) writes:
>In article <14054@reed.UUCP> minar@reed.bitnet (Nelson Minar) writes:
>>what are the options for running Unix on a 286 box, with 640k? Hard drive
>>space isn't too big of a problem, but I'd like to have both MS-DOS and Unix
>>on the same physical drive.
>
>Real Unixs will not run on a 286 (for quite a few reasons ...).  Real Unixs
>also won't run in 640k.  The one I am using requires a 386 and (I believe)
>4MB of memory (I have 8MB, which is much more reasonable).  You also need
>at least about 100MB hard disk (plus whatever you want for DOS).

The 80286 chip is fully capable of doing the task's needed for running UNIX
It has 1G of virtual memory, and a protected mode to execute task's in
multitasking. 

The problem however would be that all software should be compiled for
286 protected mode. It will not be possible to execute any MS-DOS software
because on the 286 the shift to protected mode is a one way ticket, going
back is done by a hardware reset. Furthermore the BIOS is disabled by the
protected mode, thus making it impossible to use disksystem w/o writing
your own drivers in protected mode versions. 

>The best you will be able to do is to use one of the 'baby Unixs' like Xenix,
>but even then I think you are looking at a memory upgrade ...

Some kind of baby unix is bound to come up, handling the POSIX standard on
a 286 machine. The number of 286 machines is simply to high. One OS may
be MINIX.


-- 
*     I am several thousand pages behind my reading schedule.    *
Kjeld Flarup Christensen                         kjeld@iesd.auc.dk