NAME
usage - installing and using MINIX
DESCRIPTION
This manual page describes the installation and use of MINIX
from a System Administrators point of view. It contains an
installation guide, instructions on how to do the initial
configuration and some other info. Please read this docu-
ment entirely before attempting to install MINIX. The ins-
tallation steps are in the proper order, but not all the
information you may need is presented at the right moment.
Other detailed information that may be useful can be found
in boot(8), hier(7), and in dosminix(8) if you run MINIX
under DOS.
1. MINIX UNDER DOS
Installation of MINIX to run under DOS is a nonevent.
Chances are, you are reading this manual page from an
already running MINIX system, but if not then the setup goes
like this:
Unpack the DOSMINIX.ZIP file using one of the popular ZIP
utilities, such as PKZIP or WinZIP. Next reboot Windows and
hit F8 just when you see the "Booting Windows" message.
From the menu that appears choose "Command prompt only", or
if that doesn't work "Safe mode command prompt only". Under
Windows Me you can use a startup disk to boot the PC into
DOS. Move to the directory containing the MINIX files and
type:
boot minix.mnx
Type '=' and presto, you are running MINIX. Most of the
rest of this manual, which deals mainly with running MINIX
in a true hard disk partition, does not apply to you. Your
system is already installed completely, with all binaries
and sources present, so all the talk about getting MINIX on
your disk can be skimmed over. Pay attention again when the
focus shifts to the configuration of the system. Section 9
is where this happens first. (The main challange to a DOS
installation is to figure out which parts of the installa-
tion manual do not apply.)
2. REQUIREMENTS
The minimum system MINIX can be installed on comfortably is
an IBM PC/AT or PS/2 with a 286 processor, 2 MB memory, a
720 kb diskette drive, and 35 MB free space on an AT, ESDI,
or SCSI hard disk (the latter controlled by an Adaptec
1540.) MINIX for the 386 (MINIX-386 for short) can be
installed on a machine with at least a 386sx processor, 3 MB
memory and at least 35 MB of disk space.
The minimum system MINIX can be installed on uncomfortably
is an IBM PC/XT with 640 kb memory. MINIX-386 can more or
less run in 2 MB memory. See sections 16 and 17 on "low
memory" issues.
3. MINIX INSTALLATION BACKGROUND
The objective of the installation is to create a partition
on your disk and to put MINIX into it. MINIX really
requires at least two partitions however, so the single
"primary" partition is split into two or three subparti-
tions. The s0 subpartition will contain the root file sys-
tem, the s1 subpartition may optionally contain swapspace,
and the s2 subpartition will contain the /usr file system.
What Windows calls "drives", i.e C:, D:, E:, MINIX calls
"file systems". MINIX does not use drive letters, but
requires that one file system is made a part of another file
system by "mounting" one on the other. The "root" file sys-
tem is always present and starts with the directory "/", the
root of the directory tree. The root file system contains a
few programs in /bin, device files in /dev, and configura-
tion files in /etc. This is just enough to get the system
started. MINIX will soon extend its directory tree by
mounting a file system on the /usr directory. What is hen-
ceforth known as the /usr file system contains all MINIX
programs in /usr/bin, file system sources in /usr/src, etc,
etc. The ROOT.MNX image contains the complete MINIX root
file system, but USR contains just a small subset of the
/usr file system, with just enough utilities to install
MINIX. The complete /usr file system is split up into the
USR.TAZ, SYS.TAZ and CMD.TAZ archives that are installed
later to fill /usr.
Let's suppose your first hard disk, which has device name
/dev/c0d0, has Windows already present in the first primary
partition (/dev/c0d0p0), and some free space left after
that. After MINIX is installed in that free space the disk
will look like this:
/dev/c0d0 Whole hard disk #0
/dev/c0d0p0 Windows C: drive
/dev/c0d0p1 MINIX primary partition
/dev/c0d0p1s0 MINIX root partition
/dev/c0d0p1s1 MINIX swap partition (optional)
/dev/c0d0p1s2 MINIX /usr partition
/dev/c0d0 is the sum of a partition table, /dev/c0d0p0 and
/dev/c0d0p1. Likewise is /dev/c0d0p1 the sum of a subparti-
tion table, /dev/c0d0p1s0 and /dev/c0d0p1s2. Read the "DEV-
ICES" sections for more information on MINIX devices.
4. INSTALLATION
You can install MINIX automatically or manually as described
in the sections below. The end result is the same, but
manual installation allows one to deviate from the precon-
figured choices. You may wish to read the manual pages of
the programs used below before you start. You may espe-
cially want to read boot(8) if your machine is different
from what the majority buys, because you may need to set a
few boot parameters to configure drivers. To do this type
ESC to get to the Boot Monitor prompt, set the appropriate
variables, use save to store the settings and menu to con-
tinue where you left off.
To install the system you need two diskettes: a bootable
root diskette and a diskette full of binaries to use as
/usr. These diskettes are named ROOT and USR. These two
diskettes may also be combined on a single high density
diskette. In that case the USR part is on the p2 partition.
Insert the ROOT diskette, boot the machine and type '=' to
the menu. The MINIX kernel is loaded and takes control when
you see the copyright banner. After loading the root
diskette into the RAM disk you will be asked to finish the
name of the device to mount on /usr. Type fd0p2 for a
diskette that contains both ROOT and USR, otherwise replace
ROOT by USR and type fd0. Login as root.
5. AUTOMATIC INSTALLATION
Before starting the installation, you must either have a
free partition available or have at least 35 MB not in any
partition so you can create a MINIX partition.
Type setup to start the installation script. First it
offers to install a national keyboard map. The names should
be clear, except for us-swap, which swaps the CTRL and CAPS
LOCK keys of a standard US style keyboard for people who
believe that the natural place of CTRL is next to A. The
default suggested between [ and ] is the US standard key-
board.
The next thing to do is to make a partition, for this you
are placed in a partition table editor named part. This
partition table editor is very easy to use (in the author's
opinion), but you will probably hate it. You can move all
over the place with the arrow keys, change values, and make
a mess of your partition table real quick. So if you get
into trouble, type 'q' to quit, 'n' to not write the table,
and RETURN to start over. Use the '?' key to get help.
With the '+' and '-' keys you can select the disk device to
install on, probably /dev/c0d0, the first hard disk. Type
'r' to load the partition table of the selected disk.
Either create one new partition by modifying a partition
marked "None", or reuse an existing partition by changing
its type to "MINIX" (hex code 81). DO NOT use part to
shrink an existing partition! It will destroy all data in
that partition. MINIX needs a partition of at least 20 MB,
but not larger than 128 MB (MINIX-86) or 1 GB (MINIX-386).
The system needs 35 MB in compiled state.
The script then wants to know the name of the partition
you've created. The partition name is probably still visi-
ble on the screen. Combined with the drive name you have to
type c0d0p1, c0d2p0 or something.
The next question is the amount of swapspace you want to
give MINIX. There will be a suggested value based on the
amount of memory your system has. If you have more then
enough memory then don't bother with swap. MINIX doesn't
handle it very well yet, or ever, only memory starved sys-
tems need it so that make world can run.
The new partition table is reloaded into the disk driver,
and the new MINIX partition is carved up into two or three
subpartitions, a 1440 kb root, maybe some amount of swap,
and the rest for /usr.
After making /usr, it is immediately put to use to replace
the installation /usr file system so that you can remove the
USR diskette and insert the ROOT diskette (unless they are
one and the same). The root file system is filled with the
contents of the ROOT diskette and slightly patched up to
work on the hard disk (/etc/fstab.)
You can now skip the next section and move to "TESTING", but
it may be instructive to read it anyway.
6. MANUAL INSTALLATION
The instructions that follow are at a very low level and
require you to be very careful. The big advantage is that
you know precisely what tools have been used and how every-
thing works. The disadvantage is that you may easily make a
mistake that either forces you to start over if you are
lucky, or wipes out the contents of your hard disk if you
are not. Only if you really want to do something different
should you use a manual installation. Slavishly following
the steps shown below will only make you end up with the
same result as an automatic installation.
Run part to make partitions to load the system into. The
best thing to do is to make one large primary partition of
type "MINIX" and to carve this partition up into three sub-
partitions for root, swap and /usr. The assumption is that
you will use the second partition on the first hard disk,
/dev/c0d0p1, and that c0d0p1s0 is the root subpartition,
c0d0p1s1 is swap and c0d0p1s2 is /usr. If you want to use
the first partition on the second hard disk for instance,
then substitute c0d1p0 and c0d1p0s[012] for the above. See
the section on devices below, and the manual pages of
part(8) and controller(4). Start part and select the disk
that you want to install MINIX onto. In our example it will
be /dev/c0d0.
Use part to make a single partition in the primary partition
table of type "MINIX", then hit '>' on this new partition to
make a subpartition table.
For the root subpartition you are advised to use 1440 kb
exactly. You can make it larger if you want to, but it is
advisable never to let the contents outgrow a floppy. (The
ROOT diskette is a copy of a root file system, and will be
used to fill your root subpartition.)
The second subpartition is for swapspace. You can use it to
enlarge the amount of total memory (real + swap) if your
system has less than 2M (16-bit mode) or 4M (32-bit mode).
Note that only one MINIX swap partition is needed on your
system, so if you have another MINIX partition then you can
use its swap partition instead.
Use the rest of the partition for s2, the /usr subpartition.
When you are done check that /dev/c0d0p1s0 is active (the *
after the partition number) so you can boot from it later.
If your disk has bad blocks then don't put the root or swap
subpartition on top of them. Make sure the inode tables in
the other partitions don't have bad blocks either. You can
put the subpartitions out of order on the disk if that
helps. Subpartition tables, unlike the main partition
table, are not sorted by the driver.
After making the partitions you do not have to reboot. The
disk driver reloads the partition tables on the next access
if the disk is not in use. (Open or mounted.)
To be able to boot from /dev/c0d0p1s0 you must place a mas-
ter bootstrap in /dev/c0d0p1. It has been placed there by
part if it told you that it was creating a new partition
table, but
installboot -m /dev/c0d0p1 /usr/mdec/masterboot
will put it there for sure.
Let's start by initializing the swap partition first, if you
allocated one. We may need it already, so mount it.
mkswap /dev/c0d0p1s1
mount -s /dev/c0d0p1s1
Next make a file system for on-disk /usr and copy the floppy
/usr on to it.
mkfs /dev/c0d0p1s2
readall -b /dev/c0d0p1s2 | sh
mount /dev/c0d0p1s2 /mnt
cpdir -v /usr /mnt
This will create a file system on /dev/c0d0p1s2, mount it on
/mnt, and copy the contents of the USR floppy onto it. The
call to readall marks bad blocks on the file system as unus-
able, you can omit this on a drive known to be spotless (IDE
or SCSI.)
You can now use the new /usr in place of the USR floppy:
umount /dev/c0d0p1s2
umount /dev/fd0 # fd0p2 if combined
mount /dev/c0d0p1s2 /usr
This little dance has freed up your floppy drive, so please
remove the USR diskette and replace it by the ROOT diskette.
Make a file system for the root with at least 512 inodes
(files), and fill it from the floppy:
mkfs -i 512 /dev/c0d0p1s0
mount /dev/fd0 /fd0
mount /dev/c0d0p1s0 /mnt
cpdir -v /fd0 /mnt
umount /dev/fd0
Remove /mnt/etc/issue to get rid of the "use setup" message
that greets you when you boot, and edit the file
/mnt/etc/fstab to name the devices MINIX has been installed
on. In our example it should look like this:
root=/dev/c0d0p1s0
swap=/dev/c0d0p1s1
usr=/dev/c0d0p1s2
Unmount the new root:
umount /dev/c0d0p1s0
Make it bootable:
installboot -d /dev/c0d0p1s0 /usr/mdec/bootblock boot
The automatic script would now set the rootdev and ram-
imagedev boot variables. You can do this now using the
edparams command, but it is easier to postpone it until the
testing phase. The settings should be:
rootdev=c0d0p1s0
ramimagedev=c0d0p1s0
7. TESTING
By now a new MINIX system is present on your hard disk.
Time to see if it works. Leave the ROOT diskette in the
drive and type halt. You are now going to use the power of
the Boot Monitor on the diskette to boot the MINIX partition
on the hard disk. Use the monitor command boot c0d0p1 to
boot the primary partition MINIX has been installed in. (It
is "c0d0p1" in our example.)
The hard disk bootstrap is now showing the menu again. You
can type '=' to start MINIX, but you probably want to change
the boot parameters. Hit ESC once more to get to the com-
mand prompt. The command set shows what the current parame-
ters are. Here is an example that shows how to make a menu
to either start MINIX or boot Windows:
minix(=,Minix) boot
win(w,Windows) boot c0d0p0
save
Windows is assumed to be in the first partition in the exam-
ple above (c0d0p0). When finished type menu to see if the
menu looks right. If so hit '=' to start MINIX. Log in as
root.
8. ADDING PROGRAMS AND SOURCES TO /usr
The setup command can also be used to add files from floppy
sets to the system. The USR.TAZ (programs and stuff),
SYS.TAZ (system sources), and CMD.TAZ (commands sources) are
all installed relative to the /usr directory, so the command
to use three times is
setup /usr
Setup will ask for the size of data on the floppies, which
is by default simply the entire floppy. You will see some
"Cannot make directory" errors while extracting, as some
directories already exist. Ignore these messages. You need
the USR.TAZ set if you want a working MINIX system, SYS.TAZ
if you want recompile the system or study it, and CMD.TAZ if
you also want the sources of the commands. On a disk space
starved machine you could opt to do without the commands
sources, as they are not absolutely necessary to understand
MINIX.
If your machine does not have enough memory to run
setup /usr then type these commands manually:
cd /usr
vol /dev/fd0 | zcat | tar xvfp -
If USR.TAZ is already present on the hard disk in an DOS or
Windows partition, then this command can be used under
MINIX-386 to extract it to avoid the floppy detour:
cd /usr
mtools copy c0d0p0:USR.TAZ - | setup /usr
In 16-bit mode you don't have mtools, but maybe dosread will
work:
cd /usr
dosread c0d0p0 USR.TAZ | setup /usr
The file doesn't have to be in the root directory of c0d0p0,
of course, c0d1p0:/TMP/USR.TAZ would name a file on the
first partition of the second hard disk in the directory
\TMP.
The /usr file system can also be filled through a network
from a remote host if MINIX if you can get networking going
with the NET.TAZ supplement. Use setup / to install NET.TAZ
(note that it goes into / instead of /usr), then follow the
instructions in boot(8) to configure TCP/IP and boot MINIX.
There are now two ways to fill /usr. One is to add the host
name and login name of a remote host and a remote user to
/.rhosts, as root, and to use the following command on the
remote host:
rsh -l root minix-box setup /usr < USR.TAZ
Two is to use urlget to copy the data directly from a Web or
FTP site by using these commands under MINIX:
cd /usr
urlget url.../USR.TAZ | setup /usr
The sources may be installed using exactly the same com-
mands, but with USR.TAZ replaced by SRC.TAZ. Note that this
means that the sources must also be extracted relative to
/usr.
9. NAMES
A standalone machine will have to be given a name. As root
type
echo name >/etc/hostname.file
to change the host name of your machine to name.
10. ACTIVE ON BOOT
You may want to make the MINIX partition active so that it
is automatically booted. With Windows fdisk or MINIX part,
mark the primary partition that contains MINIX active.
Using the menu you made earlier you can boot either MINIX or
Windows at a keypress. You can even set timeouts. To boot
MINIX automatically after 5 seconds:
main() {trap 5000 minix; menu}
See monitor(8) for all the details on the monitor.
If you don't trust this then you can rig up a diskette that
boots the MINIX partition when left in the drive:
installboot -m /dev/fd0 /usr/mdec/jumpboot 010
The numbers 010 indicate the device (disk or partition) that
must be booted, i.e. /dev/c0d0p1s0 in this example. Take
the name of the device, and use the disk, partition and sub-
partition numbers, or less. So c0d1p2s0 -> 120, c0d3 -> 3,
c0d2p0 -> 20.)
11. DEVICES
A crash course on the MINIX devices in /dev: The first two
hard disks are named c0d0 and c0d1. These devices address
the entire hard disk, from the first to the last byte. Each
disk has four partitions, for disk 0 they are c0d0p0,
c0d0p1, c0d0p2, and c0d0p3. And for disk 1 they are named
c0d1p0 to c0d1p3. These partitions may contain file sys-
tems, c0d0p0 often contains the MS-DOS or Windows "C:" file
system. MINIX can use these partitions for file systems
too, but you can also partition one of these "primary parti-
tions" into four so-called "subpartitions". The subparti-
tions of c0d0p0 are named c0d0p0s0, c0d0p0s1, c0d0p0s2, and
c0d0p0s3. The other partitions may have four subpartitions
that are named in the same way. See controller(4) for an
elaborate description.
You may need to add devices to /dev, because not all devices
are present to keep down the clutter. The command MAKEDEV
knows how to make devices, and DESCRIBE can tell you what an
unknown device may be, or even what all devices in /dev may
be if called without arguments. Devices are described in
dev(4), with pointers to more specific pages.
12. EDITORS
The editors available are elvis (a vi clone), elle (a simple
emacs clone), and the old MINIX mined editor. Of these edi-
tors only elvis can recover your file after a system crash.
Only mined is available at installation time. (All you need
to know about mined right now is that CTRL-X gets you out of
it.)
13. BOOT MONITOR VS. MINIX
The Boot Monitor uses the BIOS to address disks, so it has
no idea of controllers, it just lumps everything together
and ignores controller numbers. So what the monitor thinks
are d0, d1, and d2, may be c0d0 (IDE primary master), c0d2
(IDE secondary master), and c1d3 (SCSI disk at target 3).
One must keep this in mind when MINIX is installed on a disk
other than the very first. So if MINIX is installed in the
third partition of the SCSI disk, then boot d2p2 will boot
it, and rootdev=c1d3p2s0 will tell MINIX where its root file
system is.
14. NATIONAL KEYBOARDS
The directory /usr/lib/keymaps contains keymap tables for
several national keyboards. If you have a German keyboard
for instance, then
loadkeys /usr/lib/keymaps/german.map
will load the German key translation table into the keyboard
driver. Copy the map to /etc/keymap once MINIX is installed
on the hard disk, because having to type a key sequence like
one of these:
loadkezs -usr-lib-kezmaps-german.map
loqdkeys =usr=lib=key,qps=french.,qp
on a reboot gets a bit annoying after a while. Send correc-
tions and new keymaps to the person named below. (Do not
send a Dutch keymap, buy yourself a real keyboard instead.)
SUGGESTIONS
Below are a few useful suggestions. Some of the information
can be of use in other situations than described here.
15. VIRTUAL CONSOLES
Hold down the ALT key and press the left or right arrow key,
F1, or F2. This switches the console between two login ses-
sions. (Unless you have an old mono adapter, because vir-
tual consoles sit in video memory, and a mono adapter only
has memory for one.)
Note that kernel messages, including function key output,
only appear on the first console. This may be confusing,
but it keeps the other consoles clean.
16. LOW ON MEMORY
The normal installation requires that you have enough memory
for a large RAM disk. You can still install MINIX normally
if you either have a high density diskette drive for a com-
bined root+usr floppy, or you have two floppy drives of at
least 720 kb. Before booting you have to set the variable
rootdev to the same value as ramimagedev. This is slower
then a RAM disk, but saves a lot of memory.
The automatic installation script knows how to handle this
new situation. If you install manually then you have to use
cpdir -vx / /mnt
to copy the root device to disk. When it is time to fill
/usr and you only have one floppy drive then hit DEL to get
out of the installation script and reboot as described in
"TESTING". You can then finish the installation manually.
17. LOW ON MEMORY AND ONLY ONE 720 KB FLOPPY DRIVE
If you only have one 720 kb floppy drive and your system is
low on memory then you can use the TINYROOT.MNX boot image.
This image contains a small kernel with only the BIOS disk
driver, and a small root file system. You can use this disk
to boot your machine. Use the normal ROOT.MNX to install
the root file system. Keep booting your machine with
TINYROOT until you have compiled a small kernel for your
system. Use the rootdev boot variable to select the hard
disk root file system. Do not use TINYROOT for anything
other than booting, always use ROOT when mentioned.
18. FLOPPY DRIVE 1 IS A HIGH DENSITY DRIVE
If you would like to install from floppy drive 1 then you
need to copy at least one sector from the USR image onto a
diskette for drive 0. The USR bootstrap has been rigged to
boot the other drive.
19. INSTALLING ON A SECOND HARD DISK
MINIX doesn't care if it is installed on the second disk of
a system with two disks. The only problem is to get it
booted. You can either rig up a diskette to boot MINIX as
shown earlier, or you can use the same trick on the first
disk. The command
installboot -m /dev/c0d0 /usr/mdec/jumpboot 1
will lock the first disk into booting the second disk. Note
that this command modifies the disk outside a MINIX parti-
tion, overwriting a bit of code that has likely been put
there by Windows fdisk. First verify that the Boot Monitor
can boot a Windows partition, because then the MINIX master
bootstrap can do it too.
20. LOTS OF MEMORY ON A 286
You will have a hard time making MINIX use up 3 MB memory.
Memory you can spare can be used for a "second level block
cache" on the RAM disk. The File System uses the second
level cache to store copies of disk blocks that are pushed
out of the normal (primary) block cache. The size of the
primary cache is compiled into the FS server, but the size
of the second level cache can be set with the ramsize boot
variable. Set it to a number between 0 and 512. 512 kilo-
bytes is enough to keep most of the compiler cached.
21. LOTS OF MEMORY ON A 386+
Processes can be as big as you would like on a 386, but in
practice 4 MB is a lot, and 8 MB is infinite. The installa-
tion script sets up a second level cache for MINIX-386 of up
to 1024 kilobytes. This is because the default file system
cache is only 80 kb. Your first point of call is to get rid
of the poorly performing second level cache by setting
ENABLE_CACHE2 to 0 and to assign the memory used by it to
the normal block cache by enlarging the appropriate NR_BUFS
and NR_BUF_HASH constants in <minix/config.h> with as much
as you can spare. (1024 for NR_BUFS is the minimum to keep
cc -c cached. 2048 is then a nice value for NR_BUF_HASH.)
Disable the second level cache, compile a new kernel, reboot
and set ramsize to 0.
22. LOTS OF DISK SPACE
The maximum file system size is 1 GB for MINIX-386 and 128
MB for MINIX-86. (MINIX-86 can handle larger file systems,
but fsck can't check them.) Note that a MINIX file system
can only contain 65535 inodes (files), so the average file
should be 16 kb to completely fill it. It may be better to
make two smaller file systems. Besides, fsck takes forever
on a large file system.
SYSTEM ADMINISTRATION
The system has been set up with the idea that working as
root is a bad thing to do. As root you are in no way pro-
tected from doing stupid things. So don't do development as
root, but work as bin! Only in exceptional cases do you
want to become root. Being root is fun for wannabe hackers;
administrators know better.
To make life easier for bin, some programs like su(1),
install(1) and shutdown(8) treat bin and other members of
the operator group as special and allow them the privileges
of root. (One is an operator if one's group id is zero.)
Operators should share the shadow password of root by having
##root in their password field. This way they all have one
face (password) to the outside world, forming no greater
security risk than root alone.
The home directory of bin contains one important Makefile.
You can use it to recompile all the commands and libraries
of the system. Type make to see the usage message. If you
want to compile just one command then you can simply type
make to do so. To put it in its proper place you have to
type make install. Read the Makefiles in the commands and
lib subdirectories to understand how everything is put
together. If you are tight on memory then make may fail to
traverse down the source tree and also compile things. You
will have to type make in each subdirectory. You can run
make in /usr/src at the end to see if you've missed some-
thing or not.
The shell used by MINIX is a minimal version of ash, the BSD
shell. It has been modified to offer simple line editing
using the editline(3) library.
The kernel is not compiled from the master Makefile. To
make a new kernel you have to step into the tools directory.
There you can run four different make commands:
make This makes all the different kernel parts and combines
them in the file named image.
make fdboot
As above and then makes a boot floppy that you can use
to restart your system with. You are prompted for the
floppy device name.
make hdboot
First makes the image file and then copies it into the
directory /minix. If there are already two images in
that directory then the newest image will be removed to
make space for this newer image. It is assumed that
the oldest image is the most stable system image, one
that always works, and that the newest image is experi-
mental. Check beforehand what /minix contains before
you run make hdboot. Remove the oldest image if you
want another image to become the stable image. The
Boot Monitor chooses the newest image in /minix to
boot. You can use the monitor command ls minix to view
the images present, and set the image variable to the
full name of the image you want to use instead if the
newest doesn't work. The images in /minix are named
using the MINIX release and version numbers with an
extra revision number added to distinguish the images.
The first new kernel you would like to make is one config-
ured for your system. The kernel you are running now con-
tains several drivers you don't need, or may be missing
drivers that you might want. In <minix/config.h> you can
find a number of ENABLE_XXX variables that can be set to 0
to exclude, or 1 to include a particular driver. The full
list of configurable parameters and what they do are
described in config(8). It is invaluable in figuring out
what to change and how in <minix/config.h>.
Configuring a new kernel is sometimes not enough to enable
new devices, you sometimes need to use the MAKEDEV command
to make new device files in /dev. For pseudo-ttys you also
have to check if /etc/ttytab mentiones the new devices.
New additions to the system can be made in the /usr/local
tree. An empty directory tree has been set up for you and
binaries and manual pages are already in the search paths.
You can make a new user entry with the adduser command.
The TZ variable in /etc/profile tells the time zone offset
from the wall clock time to GMT. You have to change it for
your time zone. (See TZ(5).)
The function keys produce debug dumps, showing various
interesting data about the system. F1 lists processes and
F5 shows ethernet stats, which may be of use now. Read con-
sole(4) to know all the details of the screen and keyboard.
23. SYSTEM SHUTDOWN
You can't just turn a MINIX system off. MINIX must be told
to flush the modified data in the file system cache first.
The following commands/keystrokes can be used to exit MINIX
properly:
shutdown
First alert all users and then all processes of the
impending shutdown then halt or reboot the system in
one of various ways. See shutdown(8).
reboot / halt
Alert all processes of the system shutdown then reboot
or halt.
CTRL-ALT-DEL
Halt the system by running shutdown -h now.
MINIX halts by returning to the Boot Monitor, MINIX reboots
by instructing the monitor to reboot MINIX. (MINIX is just
a subprocess to the monitor.) Either halt MINIX and use
monitor commands to escape MINIX, or use shutdown -R to
reset the system.
When exiting MINIX running under DOS the Boot Monitor's exit
command will return you to the DOS prompt. The Boot Monitor
and MINIX are together just a pretty big DOS program as far
DOS is concerned.
FILES
/usr/ast Honorary home directory of Andrew S. Tanenbaum.
Doubles as the place where the default setup for
a new user is found.
SEE ALSO
dosminix(8), monitor(8), boot(8), part(8), mkfs(1),
mount(8), M(8), fstab(5), hier(7), config(8), console(4),
dev(4), adduser(8), TZ(5), mkdist(8), shutdown(8).
"Operating Systems - Design and Implementation 2/e" by
Andrew S. Tanenbaum and Albert S. Woodhull.
NOTES
The notation <file.h> refers to a C language include file in
/usr/include.
Root and bin do not have the current directory in their pro-
gram search path to avoid executing programs left around by
malicious people. This means that to run foo from the
current directory, ./foo must be typed.
BUGS
There are many PS/2 models, all different. Some will run
MINIX, some won't, some crippled if you lie to MINIX by set-
ting processor to 86. Almost no PS/2 has a standard disk,
so setting c0 to esdi or bios will be necessary.
Except for the floppy driver, none of the DMA based drivers
know about DMA being limited to a 24 bits address, i.e. the
first 16 MB. So under MINIX-386 you run a slight risk that
a tar or dd command may use a buffer above 16 MB for reading
or writing to a character device. This only happens if the
low 16 MB is taken by some huge processes, and you have more
than 16 MB, of course.
AUTHOR
Kees J. Bot <kjb@cs.vu.nl>