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IFCONFIG(8C)							  IFCONFIG(8C)

NAME
       ifconfig	- configure network interface parameters

SYNOPSIS
       /usr/etc/ifconfig interface [ address_family ]
	    [ address [	dest_address ] ] [ netmask mask	]
	    [ broadcast	address	] [ up ] [ down	] [ trailers ]
	    [ -trailers	] [ arp	] [ -arp ] [ private ]
	    [ -private ] [ metric n ] [	auto-revarp ]

       /usr/etc/ifconfig interface [ protocol_family ]

DESCRIPTION
       ifconfig	 is used to assign an address to a network interface and/or to
       configure network interface parameters.	ifconfig must be used at  boot
       time  to	 define	the network address of each interface present on a ma-
       chine; it may also be used at a later time to redefine  an  interface's
       address	or other operating parameters.	Used without options, ifconfig
       displays	the current configuration for a	network	interface.  If a  pro-
       tocol  family  is specified, ifconfig will report only the details spe-
       cific to	that protocol family.  Only the	super-user may modify the con-
       figuration of a network interface.

       The  interface  parameter is a string of	the form nameunit, for example
       le0 or ie1.  Three special interface names, -a, -ad and	-au,  are  re-
       served  and  refer  to all or a subset of the interfaces	in the system.
       If one of these interface names is given, the commands following	it are
       applied to all of the interfaces	that match:

       -a	      Apply the	commands to all	interfaces in the system.

       -ad	      Apply  the  commands  to	all ``down'' interfaces	in the
		      system.

       -au	      Apply the	commands to all	``up'' interfaces in the  sys-
		      tem.

       Since  an  interface  may receive transmissions in differing protocols,
       each of which may require separate naming schemes, the  parameters  and
       addresses  are  interpreted according to	the rules of some address fam-
       ily, specified by the address_family parameter.	The  address  families
       currently supported are ether and inet.	If no address family is	speci-
       fied, inet is assumed.

       For the TCP/IP family (inet), the address is either a host name present
       in the host name	data base (see hosts(5)) or in the Network Information
       Service (NIS) map hosts,	or a TCP/IP address expressed in the  Internet
       standard	 "dot  notation".  Typically, an Internet address specified in
       dot notation will consist of your system's network number and  the  ma-
       chine's	 unique	  host	 number.    A	typical	 Internet  address  is
       192.9.200.44, where 192.9.200 is	the network number and 44 is  the  ma-
       chine's host number.

       For the ether address family, the address is an Ethernet	address	repre-
       sented as x:x:x:x:x:x where x is	a hexadecimal number between 0 and ff.
       Only the	super-user may use the ether address family.

       If  the	dest_address  parameter	is supplied in addition	to the address
       parameter, it specifies the address of the correspondent	on  the	 other
       end of a	point to point link.

OPTIONS
       up	      Mark an interface	"up".  This happens automatically when
		      setting the first	address	on an interface.  The  up  op-
		      tion enables an interface	after an ifconfig down,	reini-
		      tializing	the hardware.

       down	      Mark an interface	"down".	 When an interface  is	marked
		      "down", the system will not attempt to transmit messages
		      through that interface.  If possible, the	interface will
		      be reset to disable reception as well.  This action does
		      not automatically	disable	routes using the interface.

       trailers	      This flag	used to	cause a	non-standard encapsulation  of
		      inet  packets  on	 certain  link levels.	Sun drivers no
		      longer use this flag, but	it is ignored for  compatibil-
		      ity.

       -trailers      Disable the use of a "trailer" link level	encapsulation.

       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 TCP/IP addresses and 10Mb/s Ethernet ad-
		      dresses.

       -arp	      Disable the use of the Address Resolution	Protocol.

       private	      Tells the	in.routed routing daemon (see routed(8C)) that
		      the interface should not be advertised.

       -private	      Specify unadvertised interfaces.

       auto-revarp    Use the Reverse Address Resolution  Protocol  (RARP)  to
		      automatically  acquire  an  address  for this interface.
		      Available	beginning with SunOS 4.1.1 Rev B.

       metric n	      Set the routing metric of	the interface to n, default 0.
		      The  routing  metric  is	used  by  the routing protocol
		      (routed(8C)).  Higher metrics have the effect of	making
		      a	 route less favorable; metrics are counted as addition
		      hops to the destination network or host.

       netmask mask   (inet only) Specify how much of the address  to  reserve
		      for  subdividing	networks  into sub-networks.  The mask
		      includes the network part	of the local address  and  the
		      subnet  part,  which is taken from the host field	of the
		      address.	The mask can be	specified as a single hexadec-
		      imal  number  with a leading 0x, with a dot-notation ad-
		      dress, or	with a pseudo-network name listed in the  net-
		      work  table  networks(5).	 The mask contains 1's for the
		      bit positions in the 32-bit address which	are to be used
		      for  the	network	and subnet parts, and 0's for the host
		      part.  The mask should contain  at  least	 the  standard
		      network portion, and the subnet field should be contigu-
		      ous with the network portion.  If	a `+' (plus  sign)  is
		      given  for the netmask value, then the network number is
		      looked up	in the NIS  netmasks.byaddr  map  (or  in  the
		      /etc/netmasks) file if not running the NIS service.

       broadcast address
		      (inet  only)  Specify  the  address  to use to represent
		      broadcasts to the	network.  The  default	broadcast  ad-
		      dress  is	 the address with a host part of all 0's.  A +
		      (plus sign) given	for the	 broadcast  value  causes  the
		      broadcast	 address  to be	reset to a default appropriate
		      for the (possibly	new) address and netmask.   Note  that
		      the arguments of ifconfig	are interpreted	left to	right,
		      and therefore

		      ifconfig -a netmask + broadcast +

		      and

		      ifconfig -a broadcast + netmask +

		      may result in different values being  assigned  for  the
		      interfaces' broadcast addresses.

EXAMPLES
       If  your	 workstation is	not attached to	an Ethernet, the ie0 interface
       should be marked	"down" as follows:

	      ifconfig ie0 down

       To print	out the	addressing information for each	interface, use

	      ifconfig -a

       To reset	each interface's broadcast address  after  the	netmasks  have
       been correctly set, use

	      ifconfig -a broadcast +

FILES
       /dev/nit
       /etc/netmasks

SEE ALSO
       intro(3),  ethers(3N), arp(4P), hosts(5), netmasks(5), networks(5) net-
       stat(8C), rc(8),	routed(8C)

DIAGNOSTICS
       Messages	indicating the specified interface does	 not  exist,  the  re-
       quested	address	is unknown, or the user	is not privileged and tried to
       alter an	interface's configuration.

NOTES
       The network information service (NIS) was formerly known	as Sun	Yellow
       Pages  (YP).   The  functionality of the	two remains the	same; only the
       name has	changed.

			       14 December 1990			  IFCONFIG(8C)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | FILES | SEE ALSO | DIAGNOSTICS | NOTES

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