Administering COHERENT -- Overview

To administer a COHERENT system, you must know how to do the following:

-> Perform backups, manage archives and purge old files.

-> Set up  and manage  complex system,  such as mail,  UUCP, and  the print
   spooler.

-> Attach peripheral devices, such as terminals, modems, and printers.

-> Install third-party software.

-> Configure the kernel, and add or configure device drivers.

-> Act as a resource person for other users.

Overview Lexicon Articles

Many users  who have  purchased COHERENT for  their personal use  will find
some of these  tasks to be confusing or daunting.   This is especially true
if they have had no previous exposure to UNIX or similar operating systems.
Such a person will find the following Lexicon articles to be helpful:

backups
     When and how to back up your system, using tape or floppy disks.

booting
     How booting works.  In particular, it shows how to boot a kernel other
     than the default kernel.

CD-ROM
     Introduce how to use CD-ROM drives under COHERENT.

console
     This introduces the device /dev/console. It also lists the many escape
     sequences with which you can change the appearance and behavior of the
     console.

device drivers
     The suite  of device drivers  available under COHERENT.   This article
     also gives a

floppy disks
     Information  about  floppy  disks.   This  describes  the  floppy-disk
     devices available under COHERENT,  how to format floppy disks, and how
     to record data  on a floppy disk using a  COHERENT file systems, a tar
     archive, or an  file systems.

hard disk
     This  gives basic  information about  hard  disks.  In  particular, it
     discusses the  devices by  which hard disks  are accessed, and  how to
     partition a hard disk.

IRQ  This article lists the IRQs available on the IBM PC.

kernel
     This introduces  the kernel, which is the  master program of COHERENT.
     It also gives examples of how to configure and patch the kernel.

keyboard
     This  introduces  the  suite of  keyboard  drivers  available for  the
     COHERENT keyboard.

lpsched
     This command is the daemon for  the lp print spooler.  For an overview
     of lp and the other print spoolers, see the Lexicon entry for printer.

mail This gives  an overview of  the COHERENT mail system  -- both commands
     and configuration files.

modem
     This describes  how to add a  modem to your COHERENT  system.  It also
     introduces the communications programs available under COHERENT.

printer
     This describes how to add a  printer to your system.  It also gives an
     overview of  the various print  spoolers available with  COHERENT, and
     how to configure each to work with a variety of printers.

RS-232
     This presents the design and pin-out  of the RS-232 plug, which is the
     standard plug  for serial  and parallel  ports on the  IBM PC  and its
     clones.

security
     This article discusses the problem  of system security -- that is, how
     to let your users but keep the ``crackers'' out.

tape This introduces  tape devices.  It  describes how to  access tape, and
     goes into some detail on how to manage tape archives.

terminal
     This describes how to plug  a terminal into your system, and configure
     it correctly.

tboot
     The tertiary  boot is the program that loads  the COHERENT kernel into
     memory and launches it.  This article describes it.  You probably will
     never need to work with tboot-- but you never know.

virtual console
     COHERENT supports  virtual consoles, whereby  several console sessions
     can be run on the same  physical device.  This describes how to set up
     and manage virtual consoles on your system.

System Files

The COHERENT system is controlled by system files and daemons. System files
contain the information that controls the minute-to-minute operation of the
COHERENT system.   A daemon is a  program that the system  runs to manage a
peripheral  device or  perform some  other task that  does not  require the
intervention of a human.  COHERENT's system files and daemons are described
in the following Lexicon articles:

/usr/lib/mail/aliases
     This file  holds the aliases  by which your  system is known  to other
     systems.

atrun
     This daemon executes other commands at  a preset time.  A user can use
     the command at to spool another command for execution at a later time.

/etc/boottime
     This file records the date and time your system was last booted.

/etc/brc
     COHERENT  executes this  script  when your  system enters  single-user
     mode.  It performs maintenance chores.

/etc/checklist
     This file lists the devices to check with fsck when you boot COHERENT.

/usr/lib/mail/config
     This file performs overall configuration of smail.

/usr/lib/uucp/config
     This file performs overall configuration of UUCP.

/usr/spool/mlp/controls
     This file holds the data base for the MLP print spooler.

core This Lexicon  entry describes the format  of a core file  -- that, the
     file that a program dumps when it fails catastrophically.

/etc/cron
     This daemon reads a data base of commands to execute periodically, and
     executes each when its time comes round at last.

/etc/d_passwd
     This file  holds the passwords that control access  to your system via
     peripheral devices.   For example,  you can  set an extra  password in
     this file for all users who may attempt to log in via modem.

/usr/lib/uucp/dial
     This file holds the information by which UUCP dials a modem.

/etc/dialups
     This file  names every peripheral  device that requires  an additional
     password.

/usr/lib/mail/directors
     Name the director routines that smail uses, and configure them.

/etc/domain
     This file names the mail domain to which your system belongs.

/etc/drvld.all
     This  file names  the  loadable drivers  to  load when  you boot  your
     system.

$HOME/.forward
     This File lets you set a forwarding address for mail.

/etc/getty
     This daemon  initializes a serial port, watches  the port, and assists
     any user who attempts to log into your system.

/etc/group
     This file define groups of users on your system.

/etc/hosts
     This  file gives  the name  and address  of every  host on  your local
     network.

/etc/hosts.equiv
     This file names ``equivalent hosts'' on your local network -- that is,
     the hosts that have identical (or nearly identical) sets of users.

/etc/hosts.lpd
     This file holds the name and domain of your local host.

/usr/lib/hpd
     This daemon is a spooler daemon for a laser printer.

/etc/inetd.conf
     This file configures the Internet daemons.

/etc/init
     Command helps  to bring COHERENT into multi-user  mode.  It also helps
     users to log in.

$HOME/.kshrc
     This script configures the Korn shell to suit your tastes.

$HOME/.lastlogin
     This  file records  the  date and  time  you last  logged  in to  your
     COHERENT system.

login
     This  command logs  a user  in to your  COHERENT system.   Its Lexicon
     article also  describes the entire  convoluted process of  managing an
     enabled port and logging a user in.

/etc/default/login
     This file sets default values for logging in.

/usr/adm/loginlog
     This file logs failed attempts to log in.

/etc/logmsg
     This file  holds the COHERENT  login prompt.  If  you do not  like the
     prompt

         Coherent 386 login:

     and a beep, you can change it by editing this file.

/usr/lib/lpd
     This daemon manages the MLP print spooler.

/etc/conf/mdevice
     This  file describes  the device drivers  currently available  on your
     system.

/etc/mnttab
     This file holds  the mount table -- that is,  the table that describes
     which file systems are  mounted, and what directories they are mounted
     on.

/etc/motd
     This file holds the message of the day -- a message that is printed on
     each user's terminal when she logs in.

/etc/mount.all
     This  file names  the disk  devices to mount  when your  system enters
     multi-user mode.

/etc/conf/mtune
     This file  names the  set of  variables in the  kernel and  its device
     drivers that you can ``tune,'' to modify the kernel's behavior.

/etc/networks
     This file describes remote networks that your system can contact.

/etc/nologin
     This file, if  it exists, prevents users from logging  in.  It is used
     during special  periods of  time, such  as when you  wish to  shut the
     system down.

/etc/passwd
     This file  describes every  user who has  permission to log  into your
     system.

/usr/lib/mail/paths
     This file  holds the information  by which your system  routes mail to
     other systems.

/usr/lib/uucp/port
     This file  describes the serial ports through which  UUCP can dial out
     from your system.

/etc/profile
     This  script sets  up the  default environment for  each user  on your
     system.

$HOME/.profile
     This script holds commands that are executed when a given user logs in
     to your COHERENT system.

/etc/protocols
     This file names the Internet protocols that your system supports.

/usr/bin/ramdisk
     This script lets you build a RAM disk on your system.

/etc/rc
     This script  is executed when your system  enters multi-user mode.  It
     normally performs standard housekeeping chores.

/usr/lib/mail/routers
     This file  names the routing programs that  smail uses, and configures
     them.

/etc/conf/sdevice
     This file holds the information by which device drivers are configured
     when you build a kernel.

/etc/serialno
     This file  holds your system's  serial number, which  you entered when
     you first installed COHERENT.

/etc/services
     This file lists the Internet services that your system supports.

/etc/shadow
     This file holds each user's password.

/etc/conf/stune
     This file sets the values of tunable kernel variables.

/usr/lib/uucp/sys
     This file describes the remote  systems that you can contact via UUCP,
     and how to contact them.

term This Lexicon article describes the format of a compiled terminfo file.

/etc/termcap
     This file holds termcap terminal-description data base.

terminfo
     This  article describes  the  terminfo terminal-description  language.
     Its data base is kept in directory /usr/lib/terminfo.

/usr/lib/mail/transports
     This  file  names  the transport  routines  that  smail  can use,  and
     configures them.

/etc/trustme
     This file names of trusted users -- that is, users who can log in even
     if file /etc/nologin exists.

/etc/ttys
     This file describes  terminal ports -- that is, the  ports via which a
     user can log in.  This includes both serial ports and pseudo-ttys.

/etc/update
     This daemon periodically flushes all buffered information to disk.

/etc/usrtime
     This file holds the time, day  of the week, and terminal line by which
     each user can log into your COHERENT system.

/etc/utmp
     This file notes  every login event that has not  yet concluded -- that
     is, a  user has logged in  but not logged out  again.  You can examine
     this file to see who is using your system at this moment.

/etc/uucpname
     This file sets  your system's UUCP name -- that  is, the name by which
     it is known to all other systems.

/etc/default/welcome
     This script  is executed whenever a  user logs in for  the first time.
     It gives the new user some basic information and advice.

/usr/adm/wtmp
     This file  notes every login  event that has  concluded -- that  is, a
     user has logged in and logged out again.  You can examine this file to
     see who has logged into your system in the past, and for how long.

Finally, the following header files also hold information on file formats:

acct.h.........Format for process-accounting file
ar.h...........Format for archive files
canon.h........Portable layout of binary data
coff.h.........Define format of COHERENT 386 objects
l.out.h........Define format of COHERENT 286 objects
mtab.h.........Currently mounted file systems
utmp.h.........Login accounting information

For a  fuller description of each  file and its contents,  see its entry in
the Lexicon.

See Also

COHERENT,
Programming COHERENT,
Using COHERENT

© 2012 by Stephen A. Ness