Linux in a Nutshell, Third Edition

Name

ifconfig

Synopsis

ifconfig [interface]

ifconfig [interface address_family parameters addresses]

Description

TCP/IP command. Assign an address to a network interface and/or configure network interface parameters. ifconfig is typically used at boot time to define the network address of each interface on a machine. It may be used at a later time to redefine an interface’s address or other parameters. Without arguments, ifconfig displays the current configuration for a network interface. Used with a single interface argument, ifconfig displays that particular interface’s current configuration.

Arguments

interface

String of the form name unit, for example, en0.

address_family

Since an interface may receive transmissions in differing protocols, each of which may require separate naming schemes, you can specify the address_family to change the interpretation of the remaining parameters. You may specify inet (the default; for TCP/IP), ax25 (AX.25 Packet Radio), ddp (Appletalk Phase 2), or ipx (Novell).

Parameters

The following parameters may be set with ifconfig:

allmulti/-allmulti

Enable/disable sending of incoming frames to the kernel’s network layer.

arp/-arp

Enable/disable use of the Address Resolution Protocol in mapping between network-level addresses and link-level addresses.

broadcast

(inet only.) Specify address to use to represent broadcasts to the network. Default is the address with a host part of all 1s (i.e., x.y.z.255 for a class C network).

debug/-debug

Enable/disable ...