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From: burgess@hrd769.brooks.af.mil (Dave Burgess)
Newsgroups: comp.os.386bsd.announce,comp.answers,news.answers
Subject: [comp.os.386bsd] Berkeley Net Release/2 derived BSD for PCs FAQ (Part 3 of 10)
Followup-To: comp.os.386bsd.announce
Date: 27 Sep 1993 13:14:27 -0000
Organization: Armstrong Laboratory, Brooks AFB, TX
Lines: 1423
Approved: news-answers-request@MIT.Edu
Distribution: world
Expires: 10/15/93
Message-ID: <386bsd-faq-3-749135665@hrd769.brooks.af.mil>
References: <386bsd-faq-1-749135665@hrd769.brooks.af.mil>
Reply-To: 386bsd-faq@hrd769.brooks.af.mil (386bsd FAQ Maintainer)
NNTP-Posting-Host: hrd769.brooks.af.mil
Posted-By: auto-faq 2.4
Archive-name: 386bsd-faq/part3
Section 2. (Common installation questions)
2.0 Install process
The 386 BSD system is distributed in many ways. One of the most
common is via DOS diskettes, (either 3 1/2 or 5 1/4, both high
density) with the actual distribution being a 'CPIO archive' broken
into 240K pieces. This allows the distribution to fit onto a
minimum number of floppies.
Once the files are on floppies, thoughts usually turn to questions
about how to install the boot image on a floppy. The rawrite
program (for DOS) is used to write the bootable images (dist.fs and
fixit.fs) onto floppies. The same image can used for 3 1/2 and
5 1/4 high density diskettes. Low density diskettes are not
supported in this version of 386bsd.
Once the bootable images are written onto the floppies, insert
the dist.fs disk into the A: drive and reboot. If the system does
not boot, see section 2.5 below for more information.
If the disk boots, type install and proceed to use the
INSTALL.NOTES to get more information.
Problems with the install are either related to hardware (i.e. Do
you want to install on your T.V.?) or software. Of the hardware
issues, the most common FAQs are usually straight out of the
installation notes. Of the software issues, there are only two
that really concern us. The first is bad files.
On some systems, files that are loaded from floppy appear to
'go bad' when they arrive on the hard disk. Try some of these
solutions:
- You forgot binary. Don't get insulted. Those of us that FTP
for a living forget sometimes. If so, the distribution will come
out with all different sizes and install will complain about every
disk.
- One or two of the files are no good. Try getting them again.
As a precaution, rename the bad files on your hard drive to names
like foo.1 and bob.23. Copy the files again from floppy. If they
are still bad, rename the file, and the one immediately before the
first bad file (bin01.23 if bin02.24 is bad) and copy them again.
If they are still bad, download those files again from the
distribution site (including the one before and after the bad one)
and try again.
The reason for renaming the files is that sometimes, especially
with drive that do not auto-magically record bad sectors, you could
copy a distribution file onto a bad spot on the disk. If this
happens, you want to isolate the bad spot. The easiest way to do
that is just leave the bad file on it.
- Keep trying, these same files have been used by literally
thousands of people to install 386bsd.
2.0.1 Tiny boot disk (versions and media formats)
There is currently one official boot disk, referred to as the
"Tiny" boot disk. In addition, there is at least one patched
unofficial boot disk available from agate and its mirror sites.
There are a few FAQs from the boot/install disk.
2.0.1.1 Where does extract go when I reboot?
It was in /tmp, which is cleaned the first time you reboot the
system from the hard drive. If you have just booted from the
hard drive for the second time, chances are you just wiped out
extract. It is not really needed, since the instructions for
building your own install are included in section 2.5.2 of
the FAQ, under custom installation.
When installing NetBSD, the set_tmp_dir and extract programs are
part of the .profile that is booted when you are installing.
This .profile is overwritten as part of the install process, and
extract then disappears. If you need extract again, you can mount
the install disk and source .profile. This will recreate these
two routines.
There is also an install procedure that NetBSD uses that does
the same job. It is defined as part of the .profile on one of the
installation floppies. You can either copy it from there, or use
the procedure for 'real disk partitioning'.
2.0.1.2 I put the floppy in and try to boot, and nothing happens. What now?
This is usually referred to as the Compaq boot problem. The easiest
solution is to get a patched boot disk. The normal source for this
disk is agate (also known by its real name agate.berkeley.edu) in
the directory /pub/386BSD/386bsd-0.1/unofficial/patchkit.
Another source of possible hope for you is to grab the NetBSD bootable
disks. They are compatible with 386BSD and allow you to install on
some of the more recalcitrant hardware.
2.0.1.3a The floppy booted, but now the hard disk won't boot?
2.0.1.3b I am trying to reinstall. I run install and it loops asking
me if I want to use the whole disk?
The most likely culprit is your hard disk controller. It is
probably doing some type of disk translation for you. If this is
the case (assume it is) then you will need to find out the real
disk controller geometry, and rewrite your disk label. See section
2.6.2, but before doing that get the program pfdisk.exe from agate
(It is out there, somewhere in the ~unofficial/ref-tfs stuff).
This program will tell you what the controller geometry is (right
before it reboots your computer). Make the disklabel agree with
this program and your system should boot. You may have to
reinstall, but at least your disklabel will be right.
NOTE: If the hard disk controller does NOT have an option for
turning off the geometry, you may well be completely out of
luck. There are very few controllers that fall into this
category. The ones that do full time translation will often
boot up in translated mode. pfdisk will help you determine the
correct geometry for your drive by telling you what the geometry
looks like when 386bsd boots up.
But on the other hand, maybe not...
See section 2.5.5 below for a detailed set of instructions about
getting NetBSD (and by implication 386BSD) to work with a system
that uses full time translation.
2.0.1.4 There are a bunch of flashing colored things on the screen. Now what?
See section 2.7 below. It gives a rather detailed description of
the cause and solution.
2.0.2 Fix-it boot disk
The fix-it disk contains a series of programs that are
particularly handy for 'fixing' your disk in case you can't get
logged in. It includes the disklabel program and other utilities
for system maintenance.
2.1 Binary distribution
The binary distribution consists of virtually all of the programs
that a typical Unix system would be expected to have. The list
includes mail, UUCP, GCC version 1.39, and others.
Known problems with the binary distribution include the following:
1. Mtools as shipped in the bindist does not always work. The
ones on the install disk seem to work fine.
2. The install script built into the binary distribution does
not correctly install all of the files and symbolic links that it
should. For example, some of the symbolic links to the
/usr/include directory are botched up.
3. 'tip', the modem control program, does not always work right
out of the box.
4. Any program that relies on a valid symbol table in the kernel
(e.g. ps) will not work because the kernel is stripped so that it
will fit onto the bootable disk.
These problems are all cured either by patches available in the
patchkit, or through re-compilation.
2.2 Source distribution
The source distribution contains all of the source code for every
program in the bindist. Known problems (which are fixed in the
patchkit) include the following:
1. There is an error message during install about install.src01
not being found. It is not an error, there isn't an install.src01.
Think of it as Bill and Lynne's idea of a practical joke.
2. There are several symbolic links that are not made correctly.
In addition, there are several files that should have been deleted
(to ensure clean 'make's) before the files were packed. This is
fixed by the patchkit, as of 0.2.3.
3. The /usr/src tree does not compile cleanly. This is fixed by
the patchkit, as of 0.2.3.
2.3 Additional software distribution
The etc distribution contains source trees for many programs that
are of interest to 386bsd users. The complete ISO software
development environment, as well as many additional software
packages (and all of the games) are included in this distribution.
The most common problem with the etc distribution is the error
"too many files open". Followed closely by "install.etc01 not
found". The latter is a annoyance (see above) but the former can
be easily overcome in a couple of ways.
The "too many files open" is a result of the "cat" command leaving
files open after it has read a file. Dwight E. Cass (his Email
address is dec@lazarus.nrtc.northrop.com) has provided us with this
anecdotal work around for his own experiences:
--------------------------------------------------------------------
So - back to installation. This time, when I get to the etc01
partition, I am a bit more awake, so I run it from Csh (with the
open file limit at 256). Works pretty well - but complains at the
end that it could not do the final configuration because it could
not find the configuration file - I checked the MANIFEST and the
file is not there, so I finally decided to ignore the message (but
it was bothersome!) Once etc01 was done - source was easy ... and
I am now up and running, and quite impressed!!!
--------------------------------------------------------------------
Another method is to use a loop construct in the Bourne shell. For
example:
for i in (etc01.*)
do
cat $i
done | compress -d | cpio -idalmu
-or-
for i in (etc01.*)
do
zcat $i
done | cpio -idalmu
will also solve the problem handily. This solution solves the problem
by running cat multiple times, with one file each. Since cat now only
has one file, there are no limits on the number of files that can be
used for the distribution set.
2.4 Patch-kit
Rod Grimes is the patchkit coordinator. It is his job to ensure
that patches suggested by the 386bsd user community integrate into
the current patchkit and do not cause new problems. His cadre of
dedicated and professional patch writers and testers work at a
fever pitch preparing and disseminating patches.
There are two mailing lists dedicated to the patchkit. They are as
follows:
386bsd-patchkit@cs.montana.edu, which is primarily for discussion of
up-coming patches and patchkit philosophy.
patches@cs.montana.edu, which is dedicated to submitting new,
untested patches.
The current version of the patchkit is 0.2.4, which has absolutely
no relationship with the new version of 386bsd. This patchkit is
available but is still in testing. Watch comp.os.386bsd.* for an
announcement of the imminent release of the 'official' patchkit.
2.5 Configuration
By far, the most common configuration questions are partitioning,
followed closely by all of the other software in the system.
Sendmail and named are also problems occasionally, but the
documentation that comes with them usually gets you through. If
you run into a problem, post a question to comp.os.386bsd.questions.
A less frequently asked question is "Where can I get info on how
to configure a kernel?" The answer to this question has been
provided by Richard Murphey (Email address rich@Rice.edu).
--------------------------------------------------------------------
Ready-to-print PostScript files for each section of the net2 system
maintainer's manual are on nova.cc.purdue.edu in
pub/386bsd/submissions/bsd.manuals.
smm.02.config.ps.Z describes kernel configuration for the VAX,
however some of it is relevant to 386BSD. There is no freely
available rewrite for 386BSD that I know of.
--------------------------------------------------------------------
2.5.1 Partitions
This section describes many of the questions that people ask about
hard disk partitioning.
The first is a brief explanation of the BSD system disk partitions.
2.5.1.1 What is a 'disklabel' and why do I need one?
The BSD partition table supplements the DOS partition table. The
entries in this table are meaningful to BSD. There are eight
partitions in the BSD partition table, and they are normally
lettered from a: to h:. This supplemental partition table is
often refereed to as the 'disklabel'.
This tutorial is provided by by "<haley@husc.harvard.edu>" and
provides an excellent overview of the hard disk partitioning
procedure from start to finish.
"Disk Partitioning for the Compleat Idiot"
There are times, in our trials with our computers, that it becomes
necessary to mess about with the disklabel. For those not
knowledgeable of BSD or Unix Systems administration, this somewhat
simple task can be somewhat daunting. This document is the result of
my own short experience.
This does not cover physical installation of the disk. For those who
are having trouble with that, I direct you to any of the fine manuals
dealing with hard drives and your hardware.
It also does not deal with the vagaries of the DOS partition manager.
It assumes you have done that as well, if need be...
After the drive is physically installed and is recognized in the BSD
startup, and it mentions both your drives, in the order you expect
them... Or perhaps just the one, if you had special problems with
installation. Now all you have to do is "disklabel" the drive... Well,
what is *THAT*???
The disklabel is used by the kernel and other utilities to tell how
you want or have the drive set up *logically*.
In a beautiful world, we might have a very free hand at this set-up
and expect it to work. Unfortunately, the authors of the software
dealing with the hard drives either decided or were forced by
circumstance to make certain things about the disklabel inviolate.
When you let the installation disk set the disklabel for you first
drive it comes out like this:
The a: partition is the primary partition.
The b: partition is the swap partition.
The c: partition is the amount of the disk used by 386bsd
(swap and data)
The d: partition is the entire disk.
Of these, the only one that could be different is a:...
(Note for those of us who have spent far too much time using DOS: the
labels a: b: c: d: e: f: g: h: DO NOT refer to DOS drives, but to
partitions in your 386bsd partition... confusing, eh? For the sake
of consistency I will never make a reference to DOS drives except by
saying something like "DOS drive C:". )
It's possible to divide up the disk a bit differently, but three
things MUST be:
c: must refer to every cylinder you wish 386bsd to use, either
for your data or the swap space.
d: Must refer to the whole disk, from cylinder 0 to the last
one...
b: Should always refer to a swap partition. Note that on any
other than the first disk it does not have to, but if you
enable swapping on that drive, and you are using b: for
something else, that something else will be killed.
The reason for this is simple: It's hard coded in.
"WHY?" you ask? (I did...) Probably time constraints, maybe tradition.
But if you look at the code in "isofs" and "ufs" in your sys.386bsd
directory, you will see numerous comments asking some of the same
questions, which leads me to believe this may change in the future,
making our lives both more complicated and easier at the same time...
Getting past the esoteric explanations, here is a method for figuring
out and "labeling" your disk.
We'll start with the disklabel from my second disk, in the form most
understandable by humans... #'s signify the start of a comment.
# /dev/rwd1d:
type: ESDI
disk: maxtor7245
label:
flags:
bytes/sector: 512
sectors/track: 31
tracks/cylinder: 16
sectors/cylinder: 496
cylinders: 967
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0 # milliseconds
track-to-track seek: 0 # milliseconds
drivedata: 0
5 partitions:
# size offset fstype [fsize bsize cpg]
a: 198400 0 4.2BSD 512 4096 16 # (Cyl. 0 - 399)
b: 31744 447392 swap # (Cyl. 902 - 965)
c: 479136 0 unused 0 0 # (Cyl. 0 - 965)
d: 479136 0 unused 0 0 # (Cyl. 0 - 965)
e: 248992 198400 4.2BSD 512 4096 16 # (Cyl. 400 - 901)
Some math:
Looking at the comments at the end and the size and offset columns,
size is a function of (last - first + 1) * sectors per cylinder:
a: 399 - 0 + 1 = 400 * 496 = 198400
b: 965 - 902 + 1 = 64 * 496 = 31744
c: & d: (Since I have no DOS partition, whatsoever)
965 - 0 = 1 = 966 * 496 = 479136
e: 901 - 400 = 502 * 496 = 248992
248992 + 198400 + 31744 = 479136 (all the parts should equal the whole)
Some things I discovered (for all you in novice land like me...)
1. As you can see this disk has 967 cylinders, but I only refer to 966
of them, 0 - 965... This is because it's good practice to leave the
"Landing Zone" cylinder out of it... This is usually the last
cylinder, and it's where the read/write heads hang out when your disk
is off...
Note from TSgt Dave:
Most modern drive heads come to rest on a polished surface inside the
highest cylinder. I could be mistaken, of course, and the Hard Drive
Bible (or other appropriate reference manual) will tell the tale for
each drive.
2. a: can be a regular partition, b: should be swap, c: everything
386bsd will get to use, including swap. d: is the entire disk from
0 - (cylinder_per_disk - 2) [leaving out the Landing Zone]
On the boot drive (The drive that actually contains the kernel), a:
is the boot partition. On all other drives, it is a regular partition.
You can then use e - h for your other partitions. I am not sure
whether you could specify b: as other than a swap partition and not
run into trouble, but you could surely make it a zero sized one
starting and stopping on the Landing Zone...
Note from TSgt Dave:
This is a good idea. Another way to accomplish this is to
simply not specify it in the map.
3. Stupid human trick: When doing the math don't forget that 400 - 900
refers to 50*1* cylinders. I did, for a while. No great problem I
suspect, but why waste a cylinder...
4. newfs'ing really is that simple if you have the label right:
"newfs /dev/rwd?x config_template" where the question mark is the
physical disk, the x is a partition letter, and the config_template
is the configuration from /etc/disktab for your disk drive.
* NOTE: This is a thumbnail sketch; read the man page to verify all
of the options and be sure about how to proceed...
5. then fsck the partition:
fsck /dev/rwd?x
Don't forget that fsck should be run on the RAW device.
6. As long as it checks out, you can then mount it and do disk things
with it...
7. Add it to the fstab... (follow the man page). Don't forget
that your new swap partition won't work if your kernel isn't
configured for it, but it won't cause you any problem to have
it there.
One last note from TSgt Dave:
And I have yet to figure out a way to determine if it is or
isn't using the swap partition anyway. There is a program called
'swapinfo' and it is part of the NetBSD source tree. On my system,
it tells me that I never use the swap area. :)
Comnonly used definitions:
bsize:
Block Size: This is the smallest allocatable area on a disk file
system, sort of. A file uses the maximum amount of blocks until it
can not completely fill up a block.
fsize:
Fragment Size: This is the size of the 'leftover' data that didn't
fit into a full block. For example, assuming a using an 8K Block
Size/1K Fragment Size, a 34.5K file, would use up 4-8K Blocks (4 *
8K = 32K) and 3 1K fragments (3 * 1K = 3K). There is 512 bytes of
wasted space, since 32K + 3K = 35K, which is 512 bytes larger than
34.5K. If you want to reduce the amount of wasted space, you can
reduce your fragment size, but you also reduce the amount of data
you read at one time, so your disk performance decreases also.
A good setup is 8K/1K for performance, but if you are really
concerned about wasted space you can consider using a 4K/512byte
filesystem.
For further information, find an article that explains the Berkeley
FFS in more detail.
cpg:
Cylinders Per Group, it determines the cylinder group size, which
in turn determines the number and location of the alternate
superblocks.
Cgd posted a description of how to manually install 386bsd and
create 'real' BSD partitions. It is excerpted below:
--------------------------------------------------------------------
HOW TO GET 386bsd 0.1 INSTALLED WITH "REAL" PARTITIONING:
(remember, if things don't work, they might be in places that aren't
normally looked in... things should work as below, but you might
have to use explicit paths occasionally... the 'better' stuff --
mount, umount, cp, etc... is in /usr/distbin on the fixit floppy...
even mknod is there, if the devices you need aren't on the fixit
floppy...)
(1) boot the fixit floppy
(2) disklabel the disk as appropriate
(3) newfs the partitions
(4) mount the new root partition under /mnt
(5) mkdir /mnt/usr
(6) mount the new /usr partition under /mnt/usr
(7) cpio the entire contents of the fixit floppy to the hard drive
cd /
ls .profile * [0-ln-z]*/* */*/* | cpio -pdalmu /mnt
(NOTE: [0-ln-z]*/* is to avoid matching mnt/mnt)
(8) copy /usr/distbin/mount and /usr/distbin/umount to /mnt (so that
they'll be in the new root partition, so you can mount the
new /usr partition...)
(9) shutdown
and the eject the floppy.
(10) reboot off the hard drive, then fsck -p <root raw device>
If there are any errors, after the fsck is done, hit
ctl-alt-delete, and repeat this step.
(11) fsck -p <usr raw device>
(12) mount -u <root device> /
(13) mount <usr device> /usr
(14) insert 0.1 boot/install floppy (dist.fs) into floppy drive
and "mount /dev/fd0a /mnt"
(15) cd /mnt
and then
usr/bin/zcat etc/baselist.Z | usr/bin/cpio -pdalmu /
(16) cd /
and then
/mnt/usr/bin/zcat /mnt/etc/baseutils.cpio.Z | /mnt/usr/bin/cpio -idalmu
(17) umount /mnt then eject the floppy
(18) umount /usr
(19) shutdown
(20) reboot off the hard drive, and get all of the various files (the
bindist files, srcdist files, etc...).
I put them into /usr/tmp, because there wasn't enough space
in /tmp (because it was on a small root partition...).
(21) cd / ; cat <all the binary files> | uncompress | cpio -idalmu
(22) rm <all the binary files>
(23) put your hostname into "/etc/myname" and put your ip addr/hostname
into /etc/hosts.
(24) make an fstab for yourself. specifically, you want something like:
<root device name> / ufs rw 1 1
<usr device name> /usr ufs rw 1 2
congratulations! you now have a working system!
you can repeat step 21 for the srcdist and etcdist files, as well,
if you wish...
2.5.2 Common Disk Label Problems.
2.5.2.1 Swap space.
Nate Williams provides a short tutorial on swap space in 386bsd,
excerpted below:
To be able to use additional swap partitions, you need to specify
them in the config (/sys/i386/conf/WHATEVER) file.
Ex:
config "386bsd" root on sd0 swap on sd0 and sd1
Allows swap on sd0 and sd1
config "386bsd" root on wd0 swap on wd0 and sd0
This would allow swap on both wd0 and sd0 OR whichever (both/either)
of the two had a valid disklabel. Note, you can really screw
yourself up with this, if you should happen to not want to swap to
this partition, and it happens to be the first one found...
The problem of not being able to swap was from the config file not
having wd1 in it.
controller wd0 at isa? port "IO_WD1" bio irq 14 vector wdintr
disk wd0 at wd0 drive 0
disk wd0 at wd0 drive 1
^^^
This should have been wd1, and that's why it didn't get added by
default. I may be wrong, but I have swapped to two different
partitions w/out any problems since patchkit 0.1, and there aren't
any patches to swap386bsd.c
Once the install is complete, swapping will not be enabled on the
second drive. The following steps can be used to make sure that it
is enabled correctly.
If there is a 'b' partition in your root disk 386bsd partition, it
will be used automatically (MAKE SURE B is not the start of the
disk, and MAKE SURE b doesn't contain any data you wish to keep).
If b starts at disk offset 0, it will promptly wipe out your boot
sectors and other important disk stuff. (This appears to be fixed
in the current NetBSD sources)
If you want an additional partition, put an entry similar to this
in /etc/fstab:
/dev/sd1b none swap sw
I'm swapping on sd0b and sd1b, and 'swapon' is run on this partition
on boot up.
Swapping to a file is still not implemented. Rumor has it 0.2 will
have such things. If someone wanted to add it, the vnops_* files
would have to be radically modified to get it to work correctly.
2.5.2.2 Increasing the 386bsd partition size.
Once the install is finished, the system has it's 386bsd partition.
This includes a 5Meg swap partition, which is altogether too small.
There is no easy way to increase this swap partition without
relabeling the drive. Unfortunately, relabeling usually involves
reinstalling. That involves re-doing just about everything you have
just finished doing. The good news is that if all you have done is
the base installation, you don't have a lot of time and energy
invested in the system. Take the time, and make sure that your swap
space is at least as big as your memory; many people recommend even
larger. There is no real limit to the size that this space can
take. If you have two disk drives, you can have space space on both.
Simply follow the instructions above, and you will be all set.
If your swap space is smaller than your real memory, system core
dumps will be disabled.
2.5.3 How do I set up the system so that I can boot from more than one
operating system/file-loader without using floppies?
There are many people that wish to be able to boot DOS or 386bsd
at will. There are several programs that allow this. The
program "os-bs" is one such program, "BOOTEASY" is another, and
there are three or four others. There are problems in some
configurations using the os/2 boot manager for this, so beware.
In addition to being able to boot from either of two partitions,
some people want to operate more than one disk drive (and perhaps
boot from either as well). Christoph Robitschko provided one
description of this. Since there are virtually limitless
possibilities for configurations for BSD systems, it will be
impossible to answer all of the possible questions about these
features. Many people operate with multiple disk drives on one
or more controllers.
Yu-Han Ting provides this tutorial on partitioning and booting
multiple systems with a single hard disk.
After spending one day fighting with the nasty partition table,
finally I had NetBSD, DOS 5 (Sorry, I don't use DOS 6), and
OS/2 2.1 March beta co-existing on my hard drive. Here is the
answer:
Since that my original hard disk setup was corrupted by NetBSD's
installation program, I decided to rebuild it. I would like my
partition table looks like this:
Partition 0: OS/2 2.1 beta (Primary, HPFS, C:)
Partition 1: MS-DOS 5.0 (Primary, C:)
Partition 2: MS-DOS 5.0 (Extended, D: & E:)
Partition 3: NetBSD
You will need the following tools before you can setup a similar
environment:
1) Mr. Wolfram's OS-BS. (It's an excellent boot selector, much
better than OS/2's boot manager, IMHO)
2) PFDISK.EXE. (It's available from wuarchive.wustl.edu:mirrors/
linux/dos_utils/pfdisktc.zip.)
3) A binary editor. I use Norton Utilities' DiskEdit.
4) 386BSD's 'tinyBSD' distribution disk.
After you have the necessary tools handy:
1) Use OS/2 'fdisk' to create partition 0. Make it install-able
and install the system as usual.
2) Use OS/2 'fdisk' to create partition 1. Assign drive C: to
the partition. Then reboot from DOS.
3) Use DOS 'fdisk' to create the extended partition. Assign logical
drive D and E to the partition.
4) Reboot from DOS again. Format drive C: (for DOS), D:, and E:.
5) Use 'tinyBSD', NOT 'NetBSD', to boot the machine. Create a genuine
386BSD partition. Once the 386BSD partition has been made,
boot DOS from floppy and execute PFDISK.EXE. For example, issue
the following commands once you get into DOS:
C>pfdisk 0 <enter>
pfdisk> L <enter> ("pfdisk>" is the command prompt and "L"
is the actual command.)
The second line, i.e., command 'L', will tell you the starting
address and the length of each partition you have. Record the
information for step 6.
6) Reboot NetBSD from floppy. Install NetBSD over the original
386BSD partition. Fill out the information you get from step
5 to the installation program. 'halt' the system after you
have installed 'install2.fs'.
(Ed.Note: This step is the same for 386bsd or NetBSD)
7) Boot OS/2 from floppy. Use fdisk to assign drive C: to the OS/2
partition. In my case, partition 0. Note that fdisk will
change the ID of partition 1 from '0x06' to '0x16'. '0x06'
stands for 16-bit DOS FAT; while '0x16' stands for non-DOS
partition. In the next step, we have to change '0x16' back to
'0x06' manually. You can get the ID information by issuing "I"
under PFDISK. It will tell you what the IDs represent.
8) Boot DOS from floppy. Use the binary editor to change the
partition type as stated in step 7.
9) Install OS-BS under DOS. Remember to enable "Modify startup ID
before booting".
10) Now you can boot any partition w/o floppy diskettes during
startup. :)
The above procedures may not be optimized. But it works for me.
I won't spend anytime to deal with tedious work again :)
You might feel strange why we need 'tinyBSD'. Simply trust me.
By using 'tinyBSD' to create a partition for NetBSD, it will
make your life a lot easier. Hope this helps.
Ed. Note: The reason is because several versions of NetBSD and
FreeBSD will not label a disk that doesn't have a disklabel.
Catch-22.
PS: %%%%% REMEMBER TO BACKUP YOUR SYSTEM BEFORE YOU CONDUCT THE
EXPERIMENT !!! %%%%%
Here is Christoph's explanation of how to set up a dual hard drive
system so that the 386BSD/NetBSD system is stored entirely on the
second hard drive.
I have done this with two IDE drives. IDE+SCSI should be a bit
simpler. There's a boot selector called BOOTEASY that can load
from the second drive (you can get it from
ftp.tu-graz.ac.at:pub/386BSD/0.1/unofficial/booteasy).
What I have done to boot 386bsd from the second (IDE) drive:
- installed booteasy on the first drive
- (you can install booteasy on the second drive, too, if you
have multiple partitions there)
- modified Julian's boot blocks to use the second drive per default
(Ed. Note: See below for the illumination of this step)
- rebuilt the kernel to have root and swap on wd1 (probably not
necessary for you, since your second disk is sd0, which is
already in the config file).
It worked perfectly for me.
This should also work with equal facility for 386bsd users.
Julian Elischer (julian@jules.dialix.oz.au) adds:
To make the bootcode default to drive 1 look in
/sys/{arch/}i386/boot/boot.c for the following (or similar.. It has
changed a little) code:
loadstart:
/***************************************************************\
* As a default set it to the first partition of the first *
* floppy or hard drive *
\***************************************************************/
part = unit = 0;
maj = (drive&0x80 ? 0 : 2); /* a good first bet */
name = names[currname++];
and change it to:
loadstart:
/***************************************************************\
* As a default set it to the first partition of the SECOND *
* floppy or hard drive *
\***************************************************************/
! part = 0;
! unit = 1;
maj = (drive&0x80 ? 0 : 2); /* a good first bet */
name = names[currname++];
2.5.4 How do I disklabel my second hard drive?
The obvious answer is to use 'disklabel -w -r /dev/rwd1d'.
Unfortunately, this does not always put a real disklabel on the
drive. The symptom is that the drive labels and can be used
until the system is reset, at which point the system tries to
read the label from the disk. It was never actually written to
the disk, so the operation fails.
There are also reports that the /usr/mdec files are corrupted in
some of the distributions. If you have tried everything else, you
can either load the files from one of the many archive sites that
keep the /usr/mdec files around, or you can recompile them
yourself.
Mark Weaver (mhw@cs.brown.edu) provides us with an illuminating
answer to this perplexing problem.
I had the same problem and there is a simple solution. I'm not
sure why this works, but it does.
Instead of specifying the entire device path name (i.e. /dev/rsd0c),
only specify the two letters of the device type and the unit number
(i.e. "sd0"). Disklabel figures out the rest, and it works.
For instance, the following line works for me:
disklabel -w -r sd0 <drive-type>
assuming of course that the boot block files are in /usr/mdec/ and
the <drive-type> is in the /etc/disktab.
This is also a symptom of some of the versions of FreeBSD and
NetBSD where the disklabel code was 'fixed' to only write a
disklabel on a drive with a disklabel. Oops.
2.5.5 386bsd/NetBSD cannot handle disk geometry translations, but it
turns out that my disk geometry is translated. It has five zones,
each with a different sec/track! What kind of things can I do
about the disk translation my hard disk controller uses?
There are several ways to get around these problems with disk
geometry translation. If you are using a SCSI controller, you can
specify the geometry such that each 'cylinder' is 1 Meg (64 sectors
by 32 tracks for example). Most SCSI controllers will blithely
ignore what YOU tell it the geometry is and press on using this
type of 1 Meg cylinder had to get the job done. NOTE: If you are
going to try this, try to ensure that each 'pseudo cylinder' is a
reasonable size (like 1Meg or 512K).
An interesting method for dealing with disk geometry comes from
Alan Barrett (barrett@lucy.ee.und.ac.za):
This sort of problem happens when you try to install NetBSD in a
partition of a disk whose controller does geometry translation. I
have not had time to find the bug that causes the problem. One
option is to disable the geometry translation: Use ide_conf to
find the true geometry, use the CMOS setup program to tell your
BIOS about the true geometry, and reformat everything. I
successfully did that on one of my systems.
If you are not able to, or do not wish to, disable the geometry
translation then the following work-around might work for you.
This requires that the disk have unused space on {cylinder 0,
head 0}, from sector 2 to sector 16. Almost all DOS disks that
I have ever seen satisfy this condition, because they usually
start the DOS partition in {cylinder 0, head 0, sector 1},
leaving most of {cylinder 0, head 0} unused apart from the
partition sector in {cylinder 0, head 0, sector 1}. However,
many partitioning programs like to hide this fact from you,
and pretend that the DOS partition starts at the front of the
disk; don't believe them until you have checked with a raw
disk editor.
0. Make sure you have adequate backups.
1. Use a partition sector editor (fdisk, pfdisk, os-bs,
booteasy, Norton utilities, whatever) to mark the partition
that you want for NetBSD as bootable with type 0xA5
(decimal 165).
2. Halt the system. Boot the NetBSD kernel copy floppy.
When it asks you to insert the floppy for the root file
system, switch to the Install-1 floppy and press enter.
3. Answer all the installation prompts, using numbers based
on the translated geometry. When it asks if you really
want to label the disk, be brave and say yes.
4. Halt the system. Boot to DOS. Run a disk editor program,
such as Norton utilities.
5.1. Verify that the partition sector in {cyl 0, head 0,
sec 1} is undamaged. Verify that the disklabel program
run as part of the NetBSD install has written the NetBSD
primary boot block to {cylinder xx, head 0, sector 1},
written the disk label to {cyl xx, head 0, sec 2}, and
written the secondary boot program to {cyl xx, head 0,
sectors 3 to 16}. ("xx" represents the translated
cylinder number you chose for the start of the NetBSD
partition. You did choose to start on a cylinder boundary,
I hope.)
5.2. Verify that the space in {cyl 0, head 0, sectors 2 to
16} is still available. Copy the fifteen sectors containing
the NetBSD disk label and secondary boot block from {cyl
xx, head 0, sectors 2 to 16} to {cyl 0, head 0, sectors 2
to 16}.
5.3. Edit the partition table in {cyl 0, head 0, sec 1}.
Change the system ID of the NetBSD partition from 0xA5
(decimal 165) to something else (I use 0xA4, decimal 164),
but keep it flagged as bootable. This will let you boot
to the NetBSD primary boot block.
5.4. Edit one of the previously unused partition table entries
(I hope you have one), to contain the following information:
{sys id = 0xA5, boot flag = 0, start cylinder/head/sector =
0/0/1, end cylinder/head/sector = anything, initial
offset = 0, total size = anything}. This will tell the
NetBSD primary boot block, or a NetBSD system booted from
a floppy, that it should look for the NetBSD disk label
in {cyl 0, head 0, sec 2}.
6. Halt the system. Boot the NetBSD kernel copy floppy. When it
asks you to insert the floppy for the root file system, just
press enter without changing disks.
7. Copy the kernel, and proceed with the rest of the installation
as per the instructions provided with NetBSD. It should now
work because of the trickery with the partition table etc.
2.6 Common installation problems.
There are many common installation problems. This section covers
the most basic and common of these problems. In addition to this
section, you should also read through the other sections of the
FAQ, since many of the less common questions are answered in other
places in the doc.
2.6.1 Swap space not identified correctly.
There are several levels of problems associated with swap space.
The first is that the swap space on a second disk will not get
used if it is not in your /etc/fstab file. Your /etc/fstab should
have the swap space identified. The following is a representative
fstab:
/dev/wd0a / ufs rw 1 1
/dev/wd1b swap swap sw 0 0
Another common question is that the install program installs the
swap partition in the 'b' partition, but does not mark it correctly
as a swap partition. The swapping software will use the swap
partition regardless of what it is called, but it should still be
identified in the disklabel as the swap partition. Use 'disklabel'
to change the partition type from 'unused' to 'swap'.
NOTE: I mean it when I say that 386bsd will use the b: partition
for swap without regard to what you called it. If it was your
root partition, it will be toast the first time you try to swap
a process out to disk. I'm not kidding!
2.6.2 Endless reboot cycles.
Endless reboot cycles are the single most vexing aspect of 386bsd.
Part of the problem is that the 0.1 distribution boot routines
were never checked against many types of computers and have bugs.
Most of the bugs are fixed in the patchkit, but that doesn't do
the average novice user any good.
In general, this will show up as a "bad disk label" error, and
can result in in not booting from the hard drive "most of the time".
You may be able to partially (or even completely) work around this
problem by making your machine run at a lower clock rate.
This problem is the result of the kernel reading the wrong register
waiting for the drive controller to come ready. On some
controllers, this isn't a problem; on others, it's fatal.
This problem is solved for almost all controllers in the patchkit.
The correct solution is to use a patched "dist.fs" or "fixit.fs"
boot disk. These have been provided by the patchkit maintainers
and are located on the machine agate.berkeley.edu in the directory
pub/386BSD/386bsd-0.1/unofficial/patchkit. In addition, new
patches kernels or a NetBSD kernel may be able to solve your
immediate problems.
Another incarnation of this symptom is that the disk geometry on
your disk label (as installed by install) is different than the
geometry that your hard drive controller thinks it is using. This
will most often manifest itself on controllers that insist on
operating in some type of translation mode. Normally the fix is to
find out what the controller geometry is and make the disk label
agree. There are programs available to help with this problem.
Julian's new boot blocks may also solve this problem. They are
available where fine precompiled kernels may be found. Also, they
are included in the patchkit as of version 0.2.2.
2.7 The computer just sits there, or 'that isn't right'.
This class of problems is sometimes caused by an incorrect FTP of
the boot disk. Make sure that the files were grabbed in 'binary'
mode and that the size reported back is 1244000 bytes. Use the
Unix program 'dd' or the DOS program RAWRITE to put these files
onto the diskette. In addition, this is the 'miscellaneous'
section of the FAQ. These problems are included here because they
are usually preceded by 'I just finished installing...'
2.7.1 The boot disk works all right on one computer but not another.
This could be a problem with many different pieces, some of which are:
- Misconfigured hardware. The iomem, IRQ, and other board settings
must match the ones listed in the INSTALL.NOTES. Unfortunately, the
INSTALL.NOTES are on the disk that will not boot. You can grab them
via FTP from /pub/386BSD/386bsd-0.1/filesystem.
- Unsupported hardware. There are several SCSI controllers on the
market that are not fully supported by 386bsd. The Ultrastore 24F
(when not running in ISA emulation mode) is a good example of this.
There are also some network cards that are not directly supported
in 386bsd. If you get into a real bind, you can post a question
to comp.os.386bsd.questions, and one of the many experienced 386bsd
gurus that reads that group will probably try to help you.
2.7.2 The screen has "flashing multicolored characters and ptdi81061
prompt" error?
The problem is that the code checking the return from the read of
the CMOS RAM value falls through in the case of an invalid value.
What really is needed is the non-existence "else" case for a bad
CMOS setup, which goes and probes memory to see it's size. What
currently happens is that the code falls through, the Maxmem is
set to zero, and the maxmem and physmem are set to -1 (this is a
bad thing).
To solve this, Terry Lambert wrote a program in (forgive him!)
Turbo C to read and write CMOS values, so that he could force the
memory count to the correct value. For a machine with a base
memory of 640K, the expected value in CMOS is 0280 (in bytes
0x16 and 0x15, respectively). What the AT&T boxes and the HP
Vectra have is 027f, so it falls through to the default case and
blows up.
The quick and dirty work-around: If you download the new patchkit
bootables from agate.berkeley.edu they have fixed these problems.
If not, you can use uzap (available for anon ftp from
wuarchive.wustl.edu, located at mirrors2/unix-c/editors/uzap.tar-z)
to binary edit the dist.fs at byte offset 946834; it should be
changed from 81FE8002 to 81FE7F02. This is the compare for 640K
in the bogus code. You can look for the pattern 81FE8002 in the
other *.fs files, including fixit.fs, and change it there, if you
MUST use one of them instead.
It should be noted that, if you download uzap, you should "touch"
uzap.c, as otherwise, make will try to use lex to create it, and
will probably fail. This is due to the tar extraction order from
the uzap tar archive.
2.7.3a I get the error "isr 15 and error: isr 17" on an NE2000 card.
2.7.3b I have some card on IRQ2 and it doesn't work; why?
2.7.3c I am getting lousy performance out of my network card. What are
some of the other possibilities?
The description of this problem is that one of the cards in your
system; most likely the VGA card, is either generating interrupts
or is causing the IRQ 2 to be actively disabled. The VGA card uses
IRQ 2 during vertical retrace to prevent sparklies.
One solution would be to plan on not using your Ethernet card until
you have rebuilt the kernel so that it expects it at an interrupt
other than IRQ 2 or 9, re-jumper or reconfigure the card to match the
IRQ you have selected, and enable it.
From time to time, this problem will manifest itself as a general
tendency of the network card to transfer either very sporadically
or very slowly. It is precisely the same problem.
James Van Artsdalen (email at james@bigtex.cactus.org) has given us
a solution:
--------------------------------------------------------------------
Some VGA cards use IRQ 2 for a vertical retrace interrupt. Even
when the interrupt is not enabled in the VGA, some cards drive
IRQ 2 inactive instead of leaving the signal tristate.
If this is the problem, you can use Scotch tape to cover the IRQ 2
signal on the VGA's ISA connector.
--------------------------------------------------------------------
There has been some discussion as to whether scotch tape is really
appropriate inside a card slot. My answer would be "yes". This is
because the alternate solution of cutting the trace on the video
board seems, to my mind, to reduce the value of the board. It is
possible that, in the future, with a bi-bipartite driver, you would
want to catch the retrace interrupt to get rid of "sparklies" or to
implement a driver for a very high resolution monitor for X. In
this happens, given a choice between alcohol and solder, I vote for
alcohol.
2.7.4 What is the difference between IRQ2 and IRQ9? Are they really
the same, or are they really different?
Holger Veit (veit@mururoa.gmd.de) says:
IRQ 2 is unused on XT systems (except for retrace on some VGA
cards), so the board might offer this as a valid interrupt.
On an AT system (including the 386/486-ISA boards) there are two
interrupt controllers. The second one is chained to the first via
interrupt line 2, so this one is actually used to forward
interrupts from the second controller. So IRQ 2 is not a good
choice. IRQ 8, which is the first interrupt line on the second
controller, serves as the "no interrupt" signal for the second
controller. So the first available interrupt on the second
controller is IRQ 9.
It is reported that on AT bus systems, the IRQ9 trace is in the
same place as the IRQ2 trace on XT bus systems.
2.7.5 Some of my SCSI devices (like a tape drive) don't work; why?
That is because the original SCSI drivers didn't recognize any
devices past the first two (ID 0 and ID 1). Also, there was a bug
in the distribution floppy regarding the devices at ID 6. The
'dev' files for that id need to be remade. Use MAKEDEV to do that.
The disks and tapes will be recognized and configured when they
are first accessed.
A new and improved SCSI driver has been written by Julian Elischer
and is available from many sources. It includes support for many
new types of SCSI controllers and many devices that are thereby
attached. This driver is included in the patchkit.
2.7.6 I try to run 'ps' or 'w' and get ': cannot get namelist'
from the TinyBSD kernel. What did I do wrong?
Nothing. There is a class of programs that interact directly with
the current kernel. These programs include 'ps', 'w', 'uptime', and
others. The shell on the TinyBSD disk is not capable of supporting
these programs because the symbol table that these programs use has
been stripped out of the kernel to save space. The easiest way to
fix this is to get a different kernel (build it yourself, or from
agate.berkeley.edu or one of the other FTP sites). Of course, you
can have a fully functional system with these programs, but they are
nice to have.
2.7.7 I get a 'Floating point constant out of range' when I try to compile
package 'n'. What is broke?
This problem was encountered during many package compilations,
including compiling gcc-2.3.3 under NetBSD-0.8.
NetBSD-0.9, and presumably FreeBSD, contain a repaired printf()
function, which corrects this problem. The easiest solution for
this (and MANY other) problems is to upgrade.
There is also a circular dependency for protoize.o/unprotoize.o
in the Makefile. Add the lines
touch protoize.o
touch unprotoize.o
after the line:
touch stamp-proto
After this "make bootstrap" will run to completion.
gas apparently has bugs too. It should produce +Infinity. I
think it is OK internally but it may be trusting the library
too much. gcc can easily be changed to avoid printf for output,
but input is harder.
One of the problems is that various pieces of code rely on the
value of DBL_MAX. A kludge to fix it is to change the line
below:
#define DBL_MAX 1.7976931348623157E+308
One value that works is
#define DBL_MAX 1.7976931348623147E+308
^ was 5
This is a kludge, but it does mostly work.
The problem is entirely in printf() (really in cvt()), NOT in
atof(). I have inspected the output of atof() bit by bit, and
it is well within IEEE specification.
The digits `157' are the `best' approximation.
The code for printf() generates a representation which is not even
in the range of doubles. Below are the details:
atof("1.7976931348623157e+308") returns
0x7fefffffffffffff
which is the maximum double value and is correct. However,
printf() of the previous yields `1.7976931348623168e+308', which
isn't even within the floating point range. It is clearly printf()
that is broken, and a quick inspection of the code is enough to
determine that it uses a pessimal algorithm.
atof() has been tested with many other values, and it has never
been off by more than is allowed by IEEE 754 (though it is not
optimal).
2.7.8 I want to use the Adaptec 1542C SCSI controller. What are the
problems/tricks you need to know to get it working?
The first thing to check when trying to use the 1542C is the setting
of 'Enable Disconnection' under the 'SCSI Device Configuration'
menu. It should be set to YES for all devices, as the manual warns
you.
Matthias Urlichs (urlichs@smurf.ira.uka.de) has provided this
description of the types of things that can cause problems for the
controller and devices attached to it.
The problem is that the Adaptec 1542C has (a) rather powerful line
drivers, and (b) is sensitive to transient signals which can be
induced by them via either a bad cable or a bad external terminator.
A bad cable is almost any cable which doesn't meet SCSI-2 specs.
A bad external terminator is one which doesn't adequately buffer
its resistor network.
So...
- Remove the internal terminator from the last drive in your chain.
Replace with an active SCSI-2 external terminator. Side
improvement: active terminators consume a bit less power.
- Check cables. Specifically, some cables carry less than the
nominal 50 signal wires. Manufacturers sometimes think they can
get away with this because almost all odd-numbered pins are GROUND
anyway. So, if pins 1 and 3 or 3 and 5 are connected, you're
likely to have a marginal cable.
- Make sure that the terminator power is supplied by all devices
and that the power pin is actually connected on your cable. The
problem here is that some idiot device manufacturers save on
2-cent diodes, which means that the thing will pull terminator
power to ground if it's not plugged in. (Two of these on one
bus are even worse.)
- Consider creating your own cabling. Take a 50-wire flat ribbon
and press the appropriate connectors onto it in precisely the
right places. (Move your devices as to minimize cable length.)
Be aware that if a device has two external connectors, you must
take the SCSI bus in at one connector and out at the other
-- don't leave the other connector dangling; this isn't within
the SCSI specs because the cable usually is too long.
- Better but more expensive: use 2-twisted cable. (I.e., wires 1&2
are twisted around each other, wire 3&4, ...) This will improve
reliability because the wires are twisted at different rates.
These cables have short non-twisted segments every 50 cm (1.5')
so that you can press on your connectors instead of heating up
that soldering iron.
- While you're rebuilding your system anyway...: If you have more
than one drive per power supply, check if these drives have
adequate condensors to buffer their power. I have two 80-MB
Seagates which refused to work more than a few hours without
glitches -- then I soldered two 10-uF Tantals onto their power
connector and they've been flawless ever since.
The terminator power is pin 26. Be aware that SCSI counts pins as
they appear on a ribbon cable, not as they're sometimes numbered
on the connectors. Pin 25 is supposed to be disconnected.
2.7.9 Did anyone ever find out on how to use the 3c509 etherlink III
card yet for bsd?
Herb Peyerl (hpeyerl@fsa.ca) responds:
I have a mostly working 3c509 driver that I've been working on
for far too long. There are a couple of problems with it that
I've addressed (in my mind mostly). I have several things I have
to do before I can go back to working on it (mostly Windsurfing,
waterskiing, suntanning, climbing, and drinking)...
I have yet to look at the recently announced Linux 3c509 driver
but plan to do that to see if it can address any of the problems
that I'm having.
I always offer to give out my existing code on the off chance i
that someone has more energy and time than I do to get it working.
But invariably I end up getting requests to photocopy and mail my
documentation which is something I'm tiring of doing.
So, to everyone who's waiting for a 3c509 driver, I say "keep
waiting, it'll happen someday"...
2.8 Other common problems that are attributed to the installation
process but are caused other places.
2.8.1 Why don't the man pages for "magic" and "file" work?
The manual page for magic and file all have two dots before the
commands, e.g.. "..SH" it should be ".SH" just delete one of the
double dots in the whole file and then it will work. These man
pages are fixed by both the patch-kit, NetBSD, and FreeBSD. The
only time this problem every occurs is when you are using the
distribution from one of the old CD-ROM distributions are get the
original 386bsd 0.1 release.
2.8.2 Why is apropos broke?
The Makefile in /usr/othersrc/share/man/Makefile creates the
whatis.db. The problem is that it doesn't strip the backspaces in
the title and apropos can't handle that. So add a "col -b" to strip
those.
excerpt from the Makefile.
makedb:
for file in `find /usr/share/man -type f -name '*.0' -print`; do \
sed -n -f /usr/share/man/makewhatis.sed $$file; \
done | col -b | sort -u > whatis.db
install -o ${BINOWN} -g ${BINGRP} -m 444 whatis.db \
${DESTDIR}/usr/share/man
This problem is also solved in the patchkit, and other *BSD releases.
Also, if the Makefile is moved to the /usr/share/man directory, the
whatis.db will reside where it needs to eventually reside, and the
install will wipe it out. An easy fix for that problem is to change
the two references of whatis.db in the excerpt above to
/tmp/whatis.db. This will ensure the file is correctly built and
installed.
2.8.3 I want to use more than 16 Megabytes of memory. Will any of the
Net/2 derived BSD systems support it?
Early on, 386bsd 0.1 would choke radically on any system that had
more than 8M of memory. With the advent of the patchkit, this
problem was, for the most part, solved; memory could then expand to
the 16M limit inherent in the ISA bus.
As people started using VESA and EISA busses, however, attempts
were made to push the envelope even further. Memory limits have
expanded seemingly without limit. Since the EISA bus (for example)
has more than the 24 address lines (the 16Meg limit), it is capable
of supporting more memory.
When using NetBSD and FreeBSD, there is no SOFTWARE limitation on
more than 16Meg of memory. There are still hardware limitations.
The limit is caused by DMA controllers which copy memory images
around the system. Many cards which people use in VESA and EISA
machines either emulate ISA cards (in order to work with *BSD) or
are really ISA cards.
Jordan K Hubbard (jkh@thrush.lotus.com) has provided this
explanation of the distinction:
Just so long as you're using a DMA-using disk controller in EISA
mode, rather than ISA mode, you can use more than 16 Meg of memory.
For those who may find such a distinction confusing, let me explain:
You can use an ISA controller (such as an Adaptec 1542) in an EISA
machine, but as it will still think it's in an ISA box and refuse to
use the extra address lines, this is no different than having an
ISA machine as far as >16MB is concerned.
You can use an EISA controller in "ISA mode", meaning it uses the
older protocols for compatability reasons (examples being Adaptec
1742 in "standard" mode, DTC 3290 in "Adaptec" mode, etc) and
again, does not use the extra address lines.
The only way to get full EISA, 32MB-of-memory-and-everything, mode
is to use an EISA controller in full EISA mode (for Adaptec 1742,
this is "enhanced" mode, for DTC 3290 it's "DTC" mode).
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
In addition, several other types of EISA controllers which do NOT
use DMA will not cause problems. IDE, ESDI, and RLL controllers
are examples of this type of card. The discussion above also applies
to VESA and VLB cards.
So, the bottom line is that you are limited to the amount of memory
that your DMA equipped devices can access. Once again, the weakest
link is the strength of your machine.
--
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TSgt Dave Burgess
NCOIC AL/Management Information Systems Office
Brooks AFB, TX