4.2BSD/usr/man/man8/ifconfig.8c

.TH IFCONFIG 8C "28 August 1983"
.UC 4
.SH NAME
ifconfig \- configure network interface parameters
.SH SYOPNSIS
.B /etc/ifconfig
interface
[
.I address
] [
.I parameters
]
.SH DESCRIPTION
.I Ifconfig
is used to assign an address
to a network interface and/or configure
network interface parameters.
.I Ifconfig
must be used at boot time to define the network address
of each interface present on a machine; it may also be used at
a later time to redefine an interface's address.  The
.I interface
parameter is a string of the form ``name unit'', e.g. ``en0'', while
the address is either a host name present in the host name data
base, 
.IR hosts (5),
or a DARPA Internet address expressed in the Internet standard
``dot notation''.
.PP
The following parameters may be set with 
.IR ifconfig :
.TP 15
.B up
Mark an interface ``up''. 
.TP 15
.B down
Mark an interface ``down''.  When an interface is
marked ``down'', the system will not attempt to
transmit messages through that interface. 
.TP 15
.B trailers
Enable the use of a ``trailer'' link level encapsulation when
sending (default).
If a network interface supports
.IR trailers ,
the system will, when possible, encapsulate outgoing
messages in a manner which minimizes the number of
memory to memory copy operations performed by the receiver.
.TP 15
.B \-trailers
Disable the use of a ``trailer'' link level encapsulation.
.TP 15
.B arp
Enable the use of the Address Resolution Protocol in mapping
between network level addresses and link level addresses (default). 
This is currently implemented for mapping between DARPA Internet
addreses and 10Mb/s Ethernet addresses.
.TP 15
.B \-arp
Disable the use of the Address Resolution Protocol.
.PP
.I Ifconfig
displays the current configuration for a network interface
when no optional parameters are supplied.
.PP
Only the super-user may modify the configuration of a network interface.
.SH DIAGNOSTICS
Messages indicating the specified interface does not exit, the
requested address is unknown, the user is not privileged and
tried to alter an interface's configuration.
.SH "SEE ALSO"
rc(8), intro(4N), netstat(1)