BOOT(8) 						      System Manager's Manual							   BOOT(8)

NAME

       boot - from power on to the login prompt

DESCRIPTION

       At  power on the machine reads the first sector of the boot device into memory and executes it.	This bootstrap code loads /boot, the Minix
       Boot Monitor.  The monitor loads the kernel binaries from /minix, or the newest file in /minix if it is a directory.

       The Minix system is now running, the different tasks initialize themselves and control is transferred to the last one, init.

       Init is the grandparent of all Minix processes, it is responsible for starting login processes on each terminal, but first it runs /etc/rc.

       /etc/rc checks the state of the system and starts daemons.  First it sets the  keyboard	translation  to  the  mapping  in  /etc/keymap	if
       present, then it reads the time zone from /etc/timeinfo followed by a call to readclock(8) to set Minix time from the hardware clock.  Next
       the file systems are checked if necessary and the /usr file system is mounted.

       The system is now ready for multiuser startup, /etc/rc starts the update(8) and cron(8) daemons,  and  initializes  the	network  services.
       /etc/rc finally recovers crashed editor buffers and cleans out the tmp directories.

       Init reads /etc/ttytab and starts a getty(8) for each enabled terminal line to allow a user to log in.

BOOT ENVIRONMENT

       Many  features of the drivers inside the kernel are controlled by settings in the boot environment.  The values of these variables are usu-
       ally colon or comma separated numbers configuring the driver.  DPETH0 = 300:10 tells the ethernet driver to use I/O address  0x300,  inter-
       rupt  request  10, and the default memory address (0xD0000, values may be omitted) for the first ethernet board.  (Note that IRQ 2 is redi-
       rected to IRQ 9 on AT's and PS/2's, so use 9 if a device is jumpered for 2.)

       Variables that are special to both the monitor and the kernel are described in monitor(8).  This section lists extra variables or  variable
       settings:

       hd = at | bios | esdi | xt
	      Choose  the  driver  that  is  to be used for the hard disk, in order: IBM/AT (classic AT or newer IDE), BIOS (generic driver), ESDI
	      (some PS/2's), or IBM/XT.  By default the first of these drivers that is enabled is used.  Most drivers are present in the kernel as
	      distributed,  but  may  be taken out by modifying /usr/include/minix/config.h.  (An XT should always use the BIOS driver, not the XT
	      driver, because BIOS calls are cheap on an XT.  The XT driver can be used on AT machines with an old XT controller.)

       DPETHn = on | off
	      Turn an ethernet board on or off.  The driver is by default in "sink" mode for all boards.  The sink mode  allows  one  to  use  the
	      driver  without  an  ethernet  board installed.  The driver will play /dev/null for that device, i.e. nothing comes in, and anything
	      send out is dropped on the floor.  If the board is turned on then the driver will use it to send out packets, if it  is  turned  off
	      then the driver will fail for that board.

       DPETHn = I/O-addr:irq:mem_addr
	      Set  the	I/O  address (hex), IRQ (decimal) and memory address (hex) of the n-th ethernet board and turn it on.  By default they are
	      configured as 280:3:D0000 and 300:5:CC000.  The memory address is ignored for the Novell ethernet boards, but may be explicitly  set
	      to  zero to indicate that the board is a Novell ethernet board.  You do not need to specify the IRQ with modern Western Digital 8013
	      compatible ethernet cards, the driver asks the board what its IRQ is.  (Note that the default IRQ conflicts with the  second  serial
	      line, so the serial line is turned off if the ethernet board is configured for IRQ 3.)

       DPETHn_EA = e0:e1:e2:e3:e4:e5
	      Set  the	ethernet  address of the n-th ethernet board.  The address is normally obtained from the ethernet board, so only in excep-
	      tional circumstances is this setting ever needed.  (Use the address of the main server if you want a career change.)

       AHA0 = I/O-addr:bus-on:bus-off:tr-speed
	      Configure the Adaptec 154xA SCSI host adapter to use the given I/O address (hex), Bus-on time (decimal), Bus-off time (decimal)  and
	      transfer speed (hex).  The default is 330:15:1:00.  The default transfer speed is always 5.0 Mb/s (code 00) ignoring the jumper set-
	      tings.

       sdn = target,lun
	      Program SCSI disk sdn to have the given target and logical unit number.  The target and lun of a tape or other SCSI  device  may	be
	      changed  by  setting  the sdn variable that would be used had it been a disk.  So tape device st7 can be set to target 4, lun 1 with
	      sd35=4,1.

       MCD = I/O-addr:irq
	      I/O address (hex) and IRQ (decimal) of the Mitsumi CD-ROM driver, by default 300:10.

TCP
/IP CONFIGURATION
       To use TCP/IP you have to compile a kernel with networking enabled, and unless you are running standalone you have to enable  the  ethernet
       driver.	 See  the  DPETHn boot variable above.	The driver supports these ethernet cards:  Western Digital 8003, Western Digital 8013, SMC
       Elite Ultra 16, Novell NE1000, Novell NE2000.  Many newer variants of the WD8013, now under the SMC brand, are also supported.

       You are likely to use TCP/IP in one of three situations:

	      Standalone with no connection to a network.

	      In a small network with no support from a "big" host.

	      Connected to a large network with address and name servers.

       In each situation you need a different set of configuration files.

   Standalone
       The machine is configured with a fixed IP address: 192.9.200.1.	This is one of the addresses Sun used to give to machines without a regis-
       tered  network  address.  This address is normally blocked at gateways, so it can do no damage if used in a real net by accident.  You need
       one file, /etc/hosts, that should look like this (using the name "darask" as an example):

	      127.0.0.1      localhost
	      192.9.200.1    darask

   Small Network
       In a network where the Minix machine can't obtain its IP address and name from a different host you need specify the  ethernet  address	to
       host  name  translation in the /etc/ethers file for use by the RARP daemon.  Suppose you have two machines in your network then /etc/ethers
       could look like this:

	      0:0:c0:a:77:23	  darask
	      0:0:c0:a:68:ce	  burask

       Use hostaddr -e to find out what the six octet ethernet address of a host is.  Use the address as printed: lowercase hex digits, no leading
       zeros.  The /etc/hosts file shows their IP addresses:

	      127.0.0.1      localhost
	      192.9.200.1    darask
	      192.9.200.2    burask

       Warning!   Do  not add ethernet addresses of diskless workstations to your ethers file.	A Sun for instance has the stupid habit of booting
       from the first RARP server that answers, probably your Minix machine...

   Large Network
       In a network with a central network administration your machine's IP address and name are given by the RARP and name services of  the  spe-
       cial servers on the network.  For a new machine you need to apply for an IP address and host name with your network administrator supplying
       the ethernet address of your machine.  You don't need any configuration files now, the irdpd  and  nonamed  daemons  automatically  find  a
       router and a name server.

       Note that no knowledge of the IP address or hostname of the Minix machine itself is necessary, it all comes from the RARP and name servers.
       A series of Minix machines can therefore set up identically.  Even if you have no RARP or name servers you can still set  them  up  identi-
       cally if you list all the Minix hosts in the hosts and ethers files.

   Simpler configuration tools
       The  rarpd,  irdpd and nonamed daemons are complex little programs that try to obtain information about their surroundings automatically to
       tell the machine what its place in the network is.  It should come as no surprise that there are simpler utilities to configure a  machine.
       On  a memory starved machine it may even be wise to configure a machine statically to get rid of the daemons.  The first daemon, rarpd, can
       be replaced by:

	      ifconfig -h host-IP-address

       to set the IP address of the machine.  Note that this is only necessary if there is no external RARP service.  The second daemon irdpd  can
       be replaced by setting a static route:

	      add_route -g router-IP-address

       (if there is a router.)	The last daemon, nonamed, can be replaced by an entry in /etc/resolv.conf that specifies an external name daemon:

	      nameserver nameserver-IP-address

       The  ifconfig  and  add_route calls can be placed in the file /etc/rc.net.  The calls to the daemons will have to be edited out of /etc/rc.
       Note that these changes undo all the efforts to make Minix TCP/IP autoconfigurable.  Make very sure that all the IP addresses are  correct,
       and  that  the  IP  address of your machine is unique.  (Mistakenly using the address of a main server will make all other machines look at
       your machine, and will make all the users of all other machines look at you.)

FILES

       /boot		   Minix Boot Monitor.

       /minix		   Kernel image, or directory containing them.

       /etc/rc		   First of the system initialization files.

       /etc/hosts	   Name to IP address mapping.

       /etc/ethers	   Name to ethernet address mapping.

SEE ALSO

       monitor(8), init(8), inet(8), loadkeys(8), readclock(8),  fsck(1),  update(8),  cron(8),  ttytab(5),  getty(8),	hostaddr(1),  ifconfig(8),
       irdpd(8), nonamed(8), rarpd(8), hosts(5), ethers(5), set_net_default(8).

DIAGNOSTICS

       Checking File Systems.
	    If	the  system has crashed then fsck is called for the root and /usr file systems.  It is wise to reboot if the root file system must
	    be fixed.

       Finish the name of device to mount as /usr: /dev/
	    If the name of the /usr file system has not been set in /etc/fstab.  You can type a device name, say fd0.

       hostaddr: unable to fetch IP address
	    TCP/IP misconfiguration.  The RARP may have failed because the ethernet address of the machine is not entered in either the remote	or
	    the local ethers file.  Either talk to your Network Administrator, or make an ethers and a hosts file.

       1.2.3.4 login:
	    If	you  see  an  IP  address  instead of a host name then the system failed to translate the IP address.  Either talk to your Network
	    Administrator to have the reverse address translation tables fixed, or make a hosts file.

NOTES

       The names "darask" and "burask" are names of cities from the Dutch translation of the novel "The Many-Colored Land"  by	Julian	May.   The
       author of this text likes names of hosts to be things that contain people, like cities and ships.

BUGS

       Indefinite  hangs  are possible if I/O addresses or IRQ's are wrong.  A driver may babble about addresses and IRQ's, but that does not mean
       that what it says is true, it may just be configured that way.  It is very difficult to find peripherals on a PC automatically,	and  Minix
       doesn't even try.

AUTHOR

       Kees J. Bot (kjb@cs.vu.nl)

																	   BOOT(8)