
SLIP (Serial Link Internet Protocol)

To build and install the slip driver, the slip utilities, and the dialslip
utilities, type the following command:

    make


SLIP DRIVER

If you are using Unix System V Release 4.0 Version 2.0 or below, you will
need to copy v2.ip.fix/Driver.o to /etc/conf/pack.d/ip/Driver.o  before you
build the kernel. The ip driver of Unix System V R4.0 V2.0 has a bug for a
point to point connection which panics the system. The v2.ip.fix/Driver.o
fixes the problem.

If you need to configure the second serial port, because your first serial
port is used by other device, refer to Intel's Unix System V Release 4.0
Administrators Guide.

Once the new ip driver and the slip have been installed, and your serial port
has been set up, you can build the kernel using the idbuild command. Don't
forget to reboot your system after the idbuild command completes succesfully
for the new kernel to take into effect.


SLIP UTILITIES

slattach

The slattach command links the slip streams driver to the serial port and links
the ip driver to the slip driver.

The syntax of slattach is as following:

    slattach [-i] nodename interface_name 
OR  slattach -d [-i] devname interface_name [ baudrate ]
OR  slattach - interface_name

The first option uses the Basic Networking Utilities (Advanced System
Administration Volume 1 Chapter 7-15). Once the administration files
are set up, you can use the remote node name to attach slip directly
or through your modem. Example:

    slattach venus sl0

The "-d" does not use BNU but directly open the next argument which is
the serial device and link it to the slip driver. The baudrate sets up
the line speed of the serial line; the default baudrate is 9600.

To start the slip interface using the first serial port at 1200 baud
execute the below command:

    slattach -d /dev/tty00 sl0 1200

If the slip hangup daemon (slhangupd) is run, slattach by default is set
to receive hangup signal (SIGHUP) sent by the slip driver through slhangupd.
The -i option ignores any hangup signal.

The - options uses stdin as the device to be attached to the SLIP driver.
This is only to be used by a dial slip utility so that a slip user can login
and use the same line as the device to be attached to SLIP.

ifconfig

This utility is included in the standard base Unix System V Release 4.0
product. Ifconfig is used to configure your system to the remote slip node.

    ifconfig interface_name source destination up


slhangupd

Slhangup (slip hangup daemon) is a daemon used to receive messages sent by
the slip driver. Whenever the slip driver receives a M_HANGUP message from
a particular line, the driver sends sends the process id of the controlling
slattach process to slhangupd. Slhangup then will send a SIGHUP (hangup
signal) to the pid received from the slip driver.

There is no restriction of the execution order of slattach and slhangupd.


sldetach

sldetach removes the serial line that is being used for slip connection.

    sldetach interface_name


DIALSLIP (slip login utilities)

To install dialslip:

1.  Set up the /etc/slip.hosts file.  This file maps login names to IP
    addresses, which # comments, as usual.

2.  Set up the /etc/slip.config file.  This file defines the IP address
    of the local system on each interface.  Set them all the same.  There
    can be as many simultaneous logins as lines in this file (not counting
    comments).

3.  Run "mkslipuser".  This builds a file similar in nature to utmp that
    keeps track of who's logged in and what interface they're using.
    This command should also be run at boot time to clean things up.

4.  Set up accounts for each system dialing in with "slip" as the shell
    with its setuid bit set to root.


MODIFICATIONS:

02/25/91  Released to public.

03/14/91  Fixed memory leak bug in the SLIP driver.
