NAME

     inet, inet.conf - TCP/IP server


SYNOPSIS

     inet


DESCRIPTION

     Inet is the TCP/IP server.   It  is  a  device  driver  that
     interfaces  between the file server and the low level ether-
     net  device  driver.   The  interface  to  this  server   is
     described in ip(4).

     Inet starts as a normal process, reads a  the  configuration
     file /etc/inet.conf to see what it should do, and uses a few
     special low level system calls to turn itself into a server.
     The format of the configuration file is as follows:

  Configuration
     The inet configuration file is fairly  simple,  here  is  an
     example:

          eth0 DP8390 0 { default; };
          psip1;

               It tells that network 0 (the one  containing  dev-
               ices  eth0,  ip0, tcp0 and udp0) uses the ethernet
               device driver handled by task "DP8390" at port  0.
               This  network is marked as the default network, so
               most programs use it through the  unnumbered  dev-
               ices  like  /dev/tcp  or /dev/udp.  Network 1 is a
               Pseudo IP network that can be used for a serial IP
               over a modem for instance.

               The configuration file may look like a common con-
               figuration file as described by configfile(5), but
               it is currently just a simple subset allowing only
               what  you see here.  The following network defini-
               tions are possible:

               ethN task port {options};
                    This sets up an  ethernet  with  device  name
                    /dev/ethN, built on the given ethernet device
                    driver at the given port at that driver.  (If
                    a  network  driver  manages two network cards
                    then they are at port 0 and 1.)

               ethN vlan id ethM {options};
                    The ethernet ethN uses VLAN number id and  is
                    built  on  ethernet  ethM.  A packet given to
                    this network has a VLAN tag  prefixed  to  it
                    and  is  then handed over to another ethernet
                    for transmission.  Likewise a packet on  that
                    ethernet  carrying  the  appropriate VLAN tag
                    has this tag removed and is sent on  to  this
                    network.   The  VLAN ethernet behaves like an
                    ordinary ethernet as far as applications  are
                    concerned.

               psipN {options};
                    Creates pseudo IP network /dev/psipN,  usable
                    for  IP  over serial lines, tunnels and what-
                    not.


OPTIONS

     Some options can be given between braces.

     default;
          Mark this network as the default network.  Exactly  one
          of  the  networks  must  be  so  marked.   When inet is
          started it will check and create all the necessary net-
          work  devices  before  becoming a server.  To know what
          major device number to use it checks /dev/ip,  so  that
          device  must  already exist.  It can be created by MAK-
          EDEV if need be.

     no ip;
     no tcp;
     no udp;
          These options turn the IP, TCP, or UDP layer off.  Inet
          will  not enable the devices for these layers, and will
          deactivate code for these layers.   Disabling  IP  will
          also  disable TCP or UDP, because they need IP to func-
          tion.  An ethernet without an IP layer can be  used  as
          for  stealth  listening.   An IP network without TCP or
          UDP can be used to pester students  into  creating  the
          missing functionality.  Keeps them off the streets, and
          maybe they'll learn something.


SEE ALSO

     ip(4), boot(8).


NOTES

     The number of networks that can be defined are 2 (Minix-86),
     4 (Minix-386) or 16 (Minix-vmd).  This limits both the total
     number and the highest device number you can use.

     Getting a network administrator  to  give  you  a  trunk  or
     multi-VLAN  port  to run multiple networks on can be a chal-
     lenge.  It questions their idea that VLANs are separate net-
     works, while in reality it is just one big ethernet.


ACKNOWLEDGMENTS

     Cindy Crawford, for providing invaluable help debugging this
     server.


AUTHOR

     Code:    Philip Homburg <philip@cs.vu.nl>
     Manual:  Kees J. Bot <kjb@cs.vu.nl>