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>