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IFCONFIG(8)		FreeBSD	System Manager's Manual		   IFCONFIG(8)

NAME
     ifconfig -- configure network interface parameters

SYNOPSIS
     ifconfig [-L] [-k]	[-m] [-n] interface [create] [address_family] [address
	      [dest_address]] [parameters]
     ifconfig interface	destroy
     ifconfig -a [-L] [-d] [-m]	[-u] [-v] [address_family]
     ifconfig -l [-d] [-u] [address_family]
     ifconfig [-L] [-d]	[-k] [-m] [-u] [-v] [-C]
     ifconfig [-g groupname]

DESCRIPTION
     The ifconfig utility is used to assign an address to a network interface
     and/or configure network interface	parameters.  The ifconfig utility 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 or other operating parameters.

     The following options are available:

     address
	     For the DARPA-Internet family, the	address	is either a host name
	     present in	the host name data base, hosts(5), or a	DARPA Internet
	     address expressed in the Internet standard	``dot notation''.

	     It	is also	possible to use	the CIDR notation (also	known as the
	     slash notation) to	include	the netmask.  That is, one can specify
	     an	address	like 192.168.0.1/16.

	     For ``inet6'' family, it is also possible to specify the prefix
	     length using the slash notation, like ::1/128.  See the prefixlen
	     parameter below for more information.

	     The link-level (``link'') address is specified as a series	of
	     colon-separated hex digits.  This can be used to e.g. set a new
	     MAC address on an ethernet	interface, though the mechanism	used
	     is	not ethernet-specific.	If the interface is already up when
	     this option is used, it will be briefly brought down and then
	     brought back up again in order to ensure that the receive filter
	     in	the underlying ethernet	hardware is properly reprogrammed.

     address_family
	     Specify the address family	which affects interpretation of	the
	     remaining parameters.  Since an interface can receive transmis-
	     sions in differing	protocols with different naming	schemes, spec-
	     ifying the	address	family is recommended.	The address or proto-
	     col families currently supported are ``inet'', ``inet6'',
	     ``atalk'',	``ipx'', and ``link''.	The default is ``inet''.
	     ``ether'' and ``lladdr'' are synonyms for ``link''.

     dest_address
	     Specify the address of the	correspondent on the other end of a
	     point to point link.

     interface
	     This parameter is a string	of the form ``name unit'', for exam-
	     ple, ``ed0''.

     groupname
	     List the interfaces in the	given group.

     The following parameters may be set with ifconfig:

     add     Another name for the alias	parameter.  Introduced for compatibil-
	     ity with BSD/OS.

     alias   Establish an additional network address for this interface.  This
	     is	sometimes useful when changing network numbers,	and one	wishes
	     to	accept packets addressed to the	old interface.	If the address
	     is	on the same subnet as the first	network	address	for this
	     interface,	a non-conflicting netmask must be given.  Usually
	     0xffffffff	is most	appropriate.

     -alias  Remove the	network	address	specified.  This would be used if you
	     incorrectly specified an alias, or	it was no longer needed.  If
	     you have incorrectly set an NS address having the side effect of
	     specifying	the host portion, removing all NS addresses will allow
	     you to respecify the host portion.

     anycast
	     (Inet6 only.)  Specify that the address configured	is an anycast
	     address.  Based on	the current specification, only	routers	may
	     configure anycast addresses.  Anycast address will	not be used as
	     source address of any of outgoing IPv6 packets.

     arp     Enable the	use of the Address Resolution Protocol (arp(4))	in
	     mapping between network level addresses and link level addresses
	     (default).	 This is currently implemented for mapping between
	     DARPA Internet addresses and IEEE 802 48-bit MAC addresses	(Eth-
	     ernet, FDDI, and Token Ring addresses).

     -arp    Disable the use of	the Address Resolution Protocol	(arp(4)).

     staticarp
	     If	the Address Resolution Protocol	is enabled, the	host will only
	     reply to requests for its addresses, and will never send any
	     requests.

     -staticarp
	     If	the Address Resolution Protocol	is enabled, the	host will per-
	     form normally, sending out	requests and listening for replies.

     broadcast
	     (Inet only.)  Specify the address to use to represent broadcasts
	     to	the network.  The default broadcast address is the address
	     with a host part of all 1's.

     debug   Enable driver dependent debugging code; usually, this turns on
	     extra console error logging.

     -debug  Disable driver dependent debugging	code.

     promisc
	     Put interface into	permanently promiscuous	mode.

     -promisc
	     Disable permanently promiscuous mode.

     delete  Another name for the -alias parameter.

     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.

     group group-name
	     Assign the	interface to a ``group''.  Any interface can be	in
	     multiple groups.

	     Cloned interfaces are members of their interface family group by
	     default.  For example, a PPP interface such as ppp0 is a member
	     of	the PPP	interface family group,	ppp.

     -group group-name
	     Remove the	interface from the given ``group''.

     eui64   (Inet6 only.)  Fill interface index (lowermost 64bit of an	IPv6
	     address) automatically.

     ipdst   This is used to specify an	Internet host who is willing to
	     receive IP	packets	encapsulating IPX packets bound	for a remote
	     network.  An apparent point to point link is constructed, and the
	     address specified will be taken as	the IPX	address	and network of
	     the destination.

     maclabel label
	     If	Mandatory Access Control support is enabled in the kernel, set
	     the MAC label to label.

     media type
	     If	the driver supports the	media selection	system,	set the	media
	     type of the interface to type.  Some interfaces support the mutu-
	     ally exclusive use	of one of several different physical media
	     connectors.  For example, a 10Mbit/s Ethernet interface might
	     support the use of	either AUI or twisted pair connectors.	Set-
	     ting the media type to 10base5/AUI	would change the currently
	     active connector to the AUI port.	Setting	it to 10baseT/UTP
	     would activate twisted pair.  Refer to the	interfaces' driver
	     specific documentation or man page	for a complete list of the
	     available types.

     mediaopt opts
	     If	the driver supports the	media selection	system,	set the	speci-
	     fied media	options	on the interface.  The opts argument is	a
	     comma delimited list of options to	apply to the interface.	 Refer
	     to	the interfaces'	driver specific	man page for a complete	list
	     of	available options.

     -mediaopt opts
	     If	the driver supports the	media selection	system,	disable	the
	     specified media options on	the interface.

     mode mode
	     If	the driver supports the	media selection	system,	set the	speci-
	     fied operating mode on the	interface to mode.  For	IEEE 802.11
	     wireless interfaces that support multiple operating modes this
	     directive is used to select between 802.11a (11a),	802.11b	(11b),
	     and 802.11g (11g) operating modes.

     inst minst, instance minst
	     Set the media instance to minst.  This is useful for devices
	     which have	multiple physical layer	interfaces (PHYs).

     name name
	     Set the interface name to name.

     rxcsum, txcsum
	     If	the driver supports user-configurable checksum offloading,
	     enable receive (or	transmit) checksum offloading on the inter-
	     face.  Some drivers may not be able to enable these flags inde-
	     pendently of each other, so setting one may also set the other.
	     The driver	will offload as	much checksum work as it can reliably
	     support, the exact	level of offloading varies between drivers.

     -rxcsum, -txcsum
	     If	the driver supports user-configurable checksum offloading,
	     disable receive (or transmit) checksum offloading on the inter-
	     face.  These settings may not always be independent of each
	     other.

     tso     If	the driver supports tcp(4) segmentation	offloading, enable TSO
	     on	the interface.	Some drivers may not be	able to	support	TSO
	     for ip(4) and ip6(4) packets, so they may enable only one of
	     them.

     -tso    If	the driver supports tcp(4) segmentation	offloading, disable
	     TSO on the	interface.  It will always disable TSO for ip(4) and
	     ip6(4).

     lro     If	the driver supports tcp(4) large receive offloading, enable
	     LRO on the	interface.

     -lro    If	the driver supports tcp(4) large receive offloading, disable
	     LRO on the	interface.

     wol, wol_ucast, wol_mcast,	wol_magic
	     Enable Wake On Lan	(WOL) support, if available.  WOL is a facil-
	     ity whereby a machine in a	low power state	may be woken in
	     response to a received packet.  There are three types of packets
	     that may wake a system: ucast (directed solely to the machine's
	     mac address), mcast (directed to a	broadcast or multicast
	     address), or magic	(unicast or multicast frames with a ``magic
	     contents'').  Not all devices support WOL,	those that do indicate
	     the mechanisms they support in their capabilities.	 wol is	a syn-
	     onym for enabling all available WOL mechanisms.  To disable WOL
	     use -wol.

     vlanmtu, vlanhwtag
	     If	the driver offers user-configurable VLAN support, enable
	     reception of extended frames or tag processing in hardware,
	     respectively.  Note that this must	be issued on a physical	inter-
	     face associated with vlan(4), not on a vlan(4) interface itself.

     -vlanmtu, -vlanhwtag
	     If	the driver offers user-configurable VLAN support, disable
	     reception of extended frames or tag processing in hardware,
	     respectively.

     polling
	     Turn on polling(4)	feature	and disable interrupts on the inter-
	     face, if driver supports this mode.

     -polling
	     Turn off polling(4) feature and enable interrupt mode on the
	     interface.

     create  Create the	specified network pseudo-device.  If the interface is
	     given without a unit number, try to create	a new device with an
	     arbitrary unit number.  If	creation of an arbitrary device	is
	     successful, the new device	name is	printed	to standard output
	     unless the	interface is renamed or	destroyed in the same ifconfig
	     invocation.

     destroy
	     Destroy the specified network pseudo-device.

     plumb   Another name for the create parameter.  Included for Solaris com-
	     patibility.

     unplumb
	     Another name for the destroy parameter.  Included for Solaris
	     compatibility.

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

     mtu n   Set the maximum transmission unit of the interface	to n, default
	     is	interface specific.  The MTU is	used to	limit the size of
	     packets that are transmitted on an	interface.  Not	all interfaces
	     support setting the MTU, and some interfaces have range restric-
	     tions.

     netmask mask
	     (Inet only.)  Specify how much of the address to reserve for sub-
	     dividing networks into sub-networks.  The mask includes the net-
	     work part of the local address and	the subnet part, which is
	     taken from	the host field of the address.	The mask can be	speci-
	     fied as a single hexadecimal number with a	leading	`0x', with a
	     dot-notation Internet address, or with a pseudo-network name
	     listed in the network 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	contiguous with	the network portion.

	     The netmask can also be specified in CIDR notation	after the
	     address.  See the address option above for	more information.

     prefixlen len
	     (Inet6 only.)  Specify that len bits are reserved for subdividing
	     networks into sub-networks.  The len must be integer, and for
	     syntactical reason	it must	be between 0 to	128.  It is almost
	     always 64 under the current IPv6 assignment rule.	If the parame-
	     ter is omitted, 64	is used.

	     The prefix	can also be specified using the	slash notation after
	     the address.  See the address option above	for more information.

     range netrange
	     Under appletalk, set the interface	to respond to a	netrange of
	     the form startnet-endnet.	Appletalk uses this scheme instead of
	     netmasks though FreeBSD implements	it internally as a set of net-
	     masks.

     remove  Another name for the -alias parameter.  Introduced	for compati-
	     bility with BSD/OS.

     phase   The argument following this specifies the version (phase) of the
	     Appletalk network attached	to the interface.  Values of 1 or 2
	     are permitted.

     link[0-2]
	     Enable special processing of the link level of the	interface.
	     These three options are interface specific	in actual effect, how-
	     ever, they	are in general used to select special modes of opera-
	     tion.  An example of this is to enable SLIP compression, or to
	     select the	connector type for some	Ethernet cards.	 Refer to the
	     man page for the specific driver for more information.

     -link[0-2]
	     Disable special processing	at the link level with the specified
	     interface.

     monitor
	     Put the interface in monitor mode.	 No packets are	transmitted,
	     and received packets are discarded	after bpf(4) processing.

     -monitor
	     Take the interface	out of monitor mode.

     up	     Mark an interface ``up''.	This may be used to enable an inter-
	     face after	an ``ifconfig down''.  It happens automatically	when
	     setting the first address on an interface.	 If the	interface was
	     reset when	previously marked down,	the hardware will be re-ini-
	     tialized.

     The following parameters are specific to IEEE 802.11 wireless interfaces:

     apbridge
	     When operating as an access point,	pass packets between wireless
	     clients directly (default).  To instead let them pass up through
	     the system	and be forwarded using some other mechanism, use
	     -apbridge.	 Disabling the internal	bridging is useful when	traf-
	     fic is to be processed with packet	filtering.

     authmode mode
	     Set the desired authentication mode in infrastructure mode.  Not
	     all adaptors support all modes.  The set of valid modes is	none,
	     open, shared (shared key),	8021x (IEEE 802.1x), and wpa (IEEE
	     WPA/WPA2/802.11i).	 The 8021x and wpa modes are only useful when
	     using an authentication service (a	supplicant for client opera-
	     tion or an	authenticator when operating as	an access point).
	     Modes are case insensitive.

     bgscan  Enable background scanning	when operating as a station.  Back-
	     ground scanning is	a technique whereby a station associated to an
	     access point will temporarily leave the channel to	scan for
	     neighboring stations.  This allows	a station to maintain a	cache
	     of	nearby access points so	that roaming between access points can
	     be	done without a lengthy scan operation.	Background scanning is
	     done only when a station is not busy and any outbound traffic
	     will cancel a scan	operation.  Background scanning	should never
	     cause packets to be lost though there may be some small latency
	     if	outbound traffic interrupts a scan operation.  By default
	     background	scanning is enabled if the device is capable.  To dis-
	     able background scanning, use -bgscan.  Background	scanning is
	     controlled	by the bgscanidle and bgscanintvl parameters.  Back-
	     ground scanning must be enabled for roaming; this is an artifact
	     of	the current implementation and may not be required in the
	     future.

     bgscanidle	idletime
	     Set the minimum time a station must be idle (not transmitting or
	     receiving frames) before a	background scan	is initiated.  The
	     idletime parameter	is specified in	milliseconds.  By default a
	     station must be idle at least 250 milliseconds before a back-
	     ground scan is initiated.	The idle time may not be set to	less
	     than 100 milliseconds.

     bgscanintvl interval
	     Set the interval at which background scanning is attempted.  The
	     interval parameter	is specified in	seconds.  By default a back-
	     ground scan is considered every 300 seconds (5 minutes).  The
	     interval may not be set to	less than 15 seconds.

     bintval interval
	     Set the interval at which beacon frames are sent when operating
	     in	ad-hoc or ap mode.  The	interval parameter is specified	in
	     TU's (1024	usecs).	 By default beacon frames are transmitted
	     every 100 TU's.

     bmissthreshold count
	     Set the number of consecutive missed beacons at which the station
	     will attempt to roam (i.e., search	for a new access point).  The
	     count parameter must be in	the range 1 to 255; though the upper
	     bound may be reduced according to device capabilities.  The
	     default threshold is 7 consecutive	missed beacons;	but this may
	     be	overridden by the device driver.  Another name for the
	     bmissthreshold parameter is bmiss.

     bssid address
	     Specify the MAC address of	the access point to use	when operating
	     as	a station in a BSS network.  This overrides any	automatic
	     selection done by the system.  To disable a previously selected
	     access point, supply any, none, or	- for the address.  This
	     option is useful when more	than one access	point uses the same
	     SSID.  Another name for the bssid parameter is ap.

     burst   Enable packet bursting.  Packet bursting is a transmission	tech-
	     nique whereby the wireless	medium is acquired once	to send	multi-
	     ple frames	and the	interframe spacing is reduced.	This technique
	     can significantly increase	throughput by reducing transmission
	     overhead.	Packet bursting	is supported by	the 802.11e QoS	speci-
	     fication and some devices that do not support QoS may still be
	     capable.  By default packet bursting is enabled if	a device is
	     capable of	doing it.  To disable packet bursting, use -burst.

     chanlist channels
	     Set the desired channels to use when scanning for access points,
	     neighbors in an IBSS network, or looking for unoccupied channels
	     when operating as an access point.	 The set of channels is	speci-
	     fied as a comma-separated list with each element in the list rep-
	     resenting either a	single channel number or a range of the	form
	     ``a-b''.  Channel numbers must be in the range 1 to 255 and be
	     permissible according to the operating characteristics of the
	     device.

     channel number
	     Set a single desired channel.  Channels range from	1 to 255, but
	     the exact selection available depends on the region your adaptor
	     was manufactured for.  Setting the	channel	to 0, any, or -	will
	     give you the default for your adaptor.  Some adaptors ignore this
	     setting unless you	are in ad-hoc mode.  Alternatively the fre-
	     quency, in	megahertz, may be specified instead of the channel
	     number.

	     When there	are several ways to use	a channel the channel num-
	     ber/frequency may be appended with	attributes to clarify.	For
	     example, if a device is capable of	operating on channel 6 with
	     802.11n and 802.11g then one can specify that g-only use should
	     be	used by	specifying ``6:g''.  Similarly the channel width can
	     be	specified by appending it with ``/''; e.g. ``6/40'' specifies
	     a 40MHz wide channel, These attributes can	be combined as in:
	     ``6:ht/40''.  The full set	of flags specified following a `:''
	     are: a (802.11a), b (802.11b), d (Atheros Dynamic Turbo mode), g
	     (802.11g),	h or n (802.11n	aka HT), s (Atheros Static Turbo
	     mode), and	t (Atheros Dynamic Turbo mode, or appended to ``st''
	     and ``dt'').  The full set	of channel widths following a '/' are:
	     5 (5MHz aka quarter-rate channel),	10 (10MHz aka half-rate	chan-
	     nel), 20 (20MHz mostly for	use in specifying ht20), and 40	(40MHz
	     mostly for	use in specifying ht40), In addition, a	40MHz HT chan-
	     nel specification may include the location	of the extension chan-
	     nel by appending ``+'' or ``-'' for above and below, respec-
	     tively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation
	     with the center channel at	frequency 2437 and the extension chan-
	     nel above.

     doth    Enable inclusion of an 802.11h country information	element	in
	     beacon frames transmitted when operating as an access point.  By
	     default 802.11h is	enabled	if the device is capable.  To disable
	     802.11h use -doth.

     deftxkey index
	     Set the default key to use	for transmission.  Typically this is
	     only set when using WEP encryption.  Note that you	must set a
	     default transmit key for the system to know which key to use in
	     encrypting	outbound traffic.  The weptxkey	is an alias for	this
	     request; it is provided for backwards compatibility.

     dtimperiod	period
	     Set the DTIM period for transmitting buffered multicast data
	     frames when operating in ap mode.	The period specifies the num-
	     ber of beacon intervals between DTIM and must be in the range 1
	     to	15.  By	default	DTIM is	1 (i.e., DTIM occurs at	each beacon).

     dturbo  Enable the	use of Atheros Dynamic Turbo mode when communicating
	     with another Dynamic Turbo-capable	station.  Dynamic Turbo	mode
	     is	an Atheros-specific mechanism by which stations	switch between
	     normal 802.11 operation and a ``boosted'' mode in which a 40MHz
	     wide channel is used for communication.  Stations using Dynamic
	     Turbo mode	operate	boosted	only when the channel is free of non-
	     dturbo stations; when a non-dturbo	station	is identified on the
	     channel all stations will automatically drop back to normal oper-
	     ation.  By	default, Dynamic Turbo mode is not enabled, even if
	     the device	is capable.  Note that turbo mode (dynamic or static)
	     is	only allowed on	some channels depending	on the regulatory con-
	     straints; use the list chan command to identify the channels
	     where turbo mode may be used.  To disable Dynamic Turbo mode use
	     -dturbo.

     fragthreshold length
	     Set the threshold for which transmitted frames are	broken into
	     fragments.	 The length argument is	the frame size in bytes	and
	     must be in	the range 256 to 2346.	Setting	length to 2346,	any,
	     or	- disables transmit fragmentation.  Not	all adaptors honor the
	     fragmentation threshold.

     hidessid
	     When operating as an access point,	do not broadcast the SSID in
	     beacon frames or respond to probe request frames unless they are
	     directed to the ap	(i.e., they include the	ap's SSID).  By
	     default, the SSID is included in beacon frames and	undirected
	     probe request frames are answered.	 To re-enable the broadcast of
	     the SSID etc., use	-hidessid.

     ff	     Enable the	use of Atheros Fast Frames when	communicating with
	     another Fast Frames-capable station.  Fast	Frames are an encapsu-
	     lation technique by which two 802.3 frames	are transmitted	in a
	     single 802.11 frame.  This	can noticeably improve throughput but
	     requires that the receiving station understand how	to decapsulate
	     the frame.	 Fast frame use	is negotiated using the	Atheros	802.11
	     vendor-specific protocol extension	so enabling use	is safe	when
	     communicating with	non-Atheros devices.  By default, use of fast
	     frames is enabled if the device is	capable.  To explicitly	dis-
	     able fast frames, use -ff.

     list active
	     Display the list of channels available for	use taking into
	     account any restrictions set with the chanlist directive.	See
	     the description of	list chan for more information.

     list caps
	     Display the adaptor's capabilities, including the operating modes
	     supported.

     list chan
	     Display the list of channels available for	use.  Channels are
	     shown with	their IEEE channel number, equivalent frequency, and
	     usage modes.  Channels identified as `11g'	are also usable	in
	     `11b' mode.  Channels identified as `11a Turbo' may be used only
	     for Atheros' Static Turbo mode (specified with mediaopt turbo).
	     Channels marked with a `*'	have a regulatory constraint that they
	     be	passively scanned.  This means a station is not	permitted to
	     transmit on the channel until it identifies the channel is	being
	     used for 802.11 communication; typically by hearing a beacon
	     frame from	an access point	operating on the channel.  list	freq
	     is	another	way of requesting this information.  By	default	a com-
	     pacted list of channels is	displayed; if the -v option is speci-
	     fied then all channels are	shown.

     list mac
	     Display the current MAC Access Control List state.	 Each address
	     is	prefixed with a	character that indicates the current policy
	     applied to	it: `+'	indicates the address is allowed access, `-'
	     indicates the address is denied access, `*' indicates the address
	     is	present	but the	current	policy open (so	the ACL	is not con-
	     sulted).

     list scan
	     Display the access	points and/or ad-hoc neighbors located in the
	     vicinity.	The -v flag may	be used	to display long	SSIDs.	-v
	     also causes received information elements to be displayed symbol-
	     icaly.  This information may be updated automatically by the
	     adaptor and/or with a scan	request	or through background scan-
	     ning.  list ap is another way of requesting this information.

     list sta
	     When operating as an access point display the stations that are
	     currently associated.  When operating in ad-hoc mode display sta-
	     tions identified as neighbors in the IBSS.	 When operating	in
	     station mode display the access point.  Capabilities advertised
	     by	the stations are described under the scan request.  Depending
	     on	the capabilities of the	stations the following flags can be
	     included in the output:

	     A	  Authorized.  Indicates that the station is permitted to
		  send/receive data frames.

	     E	  Extended Rate	Phy (ERP).  Indicates that the station is
		  operating in an 802.11g network using	extended transmit
		  rates.

	     H	  High Throughput (HT).	 Indicates that	the station is using
		  MCS to send/receive frames.

	     P	  Power	Save.  Indicates that the station is operating in
		  power	save mode.

	     Q	  Quality of Service (QoS).  Indicates that the	station	is
		  using	QoS encapsulation for data frame.  QoS encapsulation
		  is enabled only when WME mode	is enabled.

	     By	default	information elements received from associated stations
	     are displayed in a	short form; the	-v flag	causes this informa-
	     tion to be	displayed symbolicaly.

     list wme
	     Display the current parameters to use when	operating in WME mode.
	     When WME mode is enabled for an adaptor this information will be
	     displayed with the	regular	status;	this command is	mostly useful
	     for examining parameters when WME mode is disabled.  See the
	     description of the	wme directive for information on the various
	     parameters.

     mcastrate rate
	     Set the rate for transmitting multicast/broadcast frames.	Rates
	     are specified as megabits/second in decimal; e.g. 5.5 for 5.5
	     Mb/s.  This rate should be	valid for the current operating	condi-
	     tions; if an invalid rate is specified drivers are	free to	chose
	     an	appropriate rate.

     powersave
	     Enable powersave operation.  When operating as a client, the sta-
	     tion will conserve	power by periodically turning off the radio
	     and listening for messages	from the access	point telling it there
	     are packets waiting.  The station must then retrieve the packets.
	     Not all devices support power save	operation as a client.	The
	     802.11 specification requires that	all access points support
	     power save	but some drivers do not.  Use -powersave to disable
	     powersave operation when operating	as a client.

     powersavesleep sleep
	     Set the desired max powersave sleep time in TU's (1024 usecs).
	     By	default	the max	powersave sleep	time is	100 TU's.

     protmode technique
	     For interfaces operating in 802.11g, use the specified technique
	     for protecting OFDM frames	in a mixed 11b/11g network.  The set
	     of	valid techniques is off, cts (CTS to self), and	rtscts
	     (RTS/CTS).	 Technique names are case insensitive.	Not all
	     devices support cts as a protection technique.

     pureg   When operating as an access point in 802.11g mode allow only 11g-
	     capable stations to associate (11b-only stations are not permit-
	     ted to associate).	 To allow both 11g and 11b-only	stations to
	     associate,	use -pureg.

     roaming mode
	     When operating as a station, control how the system will behave
	     when communication	with the current access	point is broken.  The
	     mode argument may be one of device	(leave it to the hardware
	     device to decide),	auto (handle either in the device or the oper-
	     ating system--as appropriate), manual (do nothing until explic-
	     itly instructed).	By default, the	device is left to handle this
	     if	it is capable; otherwise, the operating	system will automati-
	     cally attempt to reestablish communication.  Manual mode is used
	     by	applications such as wpa_supplicant(8) that want to control
	     the selection of an access	point.

     roam:rssi11a rssi
	     Set the threshold for controlling roaming when operating in an
	     802.11a BSS.  The rssi parameter specifies	the receive signal
	     strength in dBm units at which roaming should be considered.  If
	     the current rssi drops below this setting and background scanning
	     is	enabled, then the system will check if a more desirable	access
	     point is available	and switch over	to it.	The current scan cache
	     contents are used if they are considered valid according to the
	     scanvalid parameter; otherwise a background scan operation	is
	     triggered before any selection occurs.  By	default	rssi is	set to
	     7 dBm.

     roam:rssi11b rssi
	     Set the threshold for controlling roaming when operating in an
	     802.11b-only BSS.	See roam:rssi11a for a description of this
	     parameter.	 By default rssi is set	to 7 dBm.

     roam:rssi11g rssi
	     Set the threshold for controlling roaming when operating in a
	     (mixed) 802.11g BSS.  See roam:rssi11a for	a description of this
	     parameter.	 By default rssi is set	to 7 dBm.

     roam:rate11a rate
	     Set the threshold for controlling roaming when operating in an
	     802.11a BSS.  The rate parameter specifies	the transmit rate in
	     megabits at which roaming should be considered.  If the current
	     transmit rate drops below this setting and	background scanning is
	     enabled, then the system will check if a more desirable access
	     point is available	and switch over	to it.	The current scan cache
	     contents are used if they are considered valid according to the
	     scanvalid parameter; otherwise a background scan operation	is
	     triggered before any selection occurs.  By	default	rate is	set to
	     12	Mb/s.

     roam:rate11b rate
	     Set the threshold for controlling roaming when operating in an
	     802.11b-only BSS.	See roam:rate11a for a description of this
	     parameter.	 By default rate is set	to 1 Mb/s.

     roam:rate11g rate
	     Set the threshold for controlling roaming when operating in a
	     (mixed) 802.11g BSS.  See roam:rate11a for	a description of this
	     parameter.	 By default rate is set	to 5 Mb/s.

     rtsthreshold length
	     Set the threshold for which transmitted frames are	preceded by
	     transmission of an	RTS control frame.  The	length argument	is the
	     frame size	in bytes and must be in	the range 1 to 2346.  Setting
	     length to 2346, any, or - disables	transmission of	RTS frames.
	     Not all adaptors support setting the RTS threshold.

     ssid ssid
	     Set the desired Service Set Identifier (aka network name).	 The
	     SSID is a string up to 32 characters in length and	may be speci-
	     fied as either a normal string or in hexadecimal when preceded by
	     `0x'.  Additionally, the SSID may be cleared by setting it	to
	     `-'.

     scan    Initiate a	scan of	neighboring stations, wait for it to complete,
	     and display all stations found.  Only the super-user can initiate
	     a scan.  Depending	on the capabilities of the APs,	the following
	     flags can be included in the output:

	     A	  Channel Agility.  Indicates that the station support channel
		  hopping as described by the IEEE 802.11b specification.

	     B	  Packet Binary	Convolution Code (PBCC).  A modulation alter-
		  native to the	standard OFDM method.

	     C	  Pollreq

	     c	  Pollable

	     D	  Direct Sequence Spread Spectrum (DSSSOFDM).  Indicates the
		  the station supports DSSS modulation.

	     E	  Extended Service Set (ESS).  Indicates that the station is
		  part of an infrastructure network (in	contrast to an
		  IBSS/ad-hoc network).

	     I	  IBSS/ad-hoc network.	Indicates that the station is part of
		  an ad-hoc network (in	contrast to an ESS network).

	     P	  Privacy.  Data confidentiality is required for all data
		  frames exchanged within the BSS.  This means that this BSS
		  requires the station to use cryptographic means such as WEP,
		  TKIP or AES-CCMP to encrypt/decrypt data frames being
		  exchanged with others.

	     R	  Robust Security Network (RSN).  Indicates that the station
		  supports the IEEE 802.11i authentication and key management
		  protocol.

	     S	  Short	Preamble.  Indicates that the network is using short
		  preambles (defined in	802.11b	High Rate/DSSS PHY, short pre-
		  amble	utilizes a 56 bit sync field in	contrast to a 128 bit
		  field	used in	long preamble mode).

	     s	  Short	slot time.  Indicates that the network is using	a
		  short	slot time.

	     Interesting information elements captured from the	neighboring
	     stations are displayed at the end of each row.  Possible elements
	     are: WME (station supports	WME), WPA (station supports WPA), WPS
	     (station supports WPS), RSN (station supports 802.11i/RSN), HT
	     (station supports 802.11n/HT communication), ATH (station
	     supoprts Atheros protocol extensions), VEN	(station supports
	     unknown vendor-specific extensions).  If the -v flag is used the
	     information element contents will be shown.

	     The list scan request can be used to show recent scan results
	     without initiating	a new scan.

	     The -v flag may be	used to	prevent	the shortening of long SSIDs.

     scanvalid threshold
	     Set the maximum time the scan cache contents are considered
	     valid; i.e. will be used without first triggering a scan opera-
	     tion to refresh the data.	The threshold parameter	is specified
	     in	seconds	and defaults to	60 seconds.  The minimum setting for
	     threshold is 10 seconds.  One should take care setting this
	     threshold;	if it is set too low then attempts to roam to another
	     access point may trigger unnecessary background scan operations.

     stationname name
	     Set the name of this station.  The	station	name is	not part of
	     the IEEE 802.11 protocol though some interfaces support it.  As
	     such it only seems	to be meaningful to identical or virtually
	     identical equipment.  Setting the station name is identical in
	     syntax to setting the SSID.

     txpower power
	     Set the power used	to transmit frames.  The power argument	is
	     specified in .5 dBm units.	 Out of	range values are truncated.
	     Typically only a few discreet power settings are available	and
	     the driver	will use the setting closest to	the specified value.
	     Not all adaptors support changing the transmit power.

     wepmode mode
	     Set the desired WEP mode.	Not all	adaptors support all modes.
	     The set of	valid modes is off, on,	and mixed.  The	mixed mode
	     explicitly	tells the adaptor to allow association with access
	     points which allow	both encrypted and unencrypted traffic.	 On
	     these adaptors, on	means that the access point must only allow
	     encrypted connections.  On	other adaptors,	on is generally
	     another name for mixed.  Modes are	case insensitive.

     weptxkey index
	     Set the WEP key to	be used	for transmission.  This	is the same as
	     setting the default transmission key with deftxkey.

     wepkey key|index:key
	     Set the selected WEP key.	If an index is not given, key 1	is
	     set.  A WEP key will be either 5 or 13 characters (40 or 104
	     bits) depending of	the local network and the capabilities of the
	     adaptor.  It may be specified either as a plain string or as a
	     string of hexadecimal digits preceded by `0x'.  For maximum
	     portability, hex keys are recommended; the	mapping	of text	keys
	     to	WEP encryption is usually driver-specific.  In particular, the
	     Windows drivers do	this mapping differently to FreeBSD.  A	key
	     may be cleared by setting it to `-'.  If WEP is supported then
	     there are at least	four keys.  Some adaptors support more than
	     four keys.	 If that is the	case, then the first four keys (1-4)
	     will be the standard temporary keys and any others	will be	adap-
	     tor specific keys such as permanent keys stored in	NVRAM.

	     Note that you must	set a default transmit key with	deftxkey for
	     the system	to know	which key to use in encrypting outbound	traf-
	     fic.

     wme     Enable Wireless Multimedia	Extensions (WME) support, if avail-
	     able, for the specified interface.	 WME is	a subset of the	IEEE
	     802.11e standard to support the efficient communication of	real-
	     time and multimedia data.	To disable WME support,	use -wme.

	     The following parameters are meaningful only when WME support is
	     in	use.  Parameters are specified per-AC (Access Category)	and
	     split into	those that are used by a station when acting as	an
	     access point and those for	client stations	in the BSS.  The lat-
	     ter are received from the access point and	may not	be changed (at
	     the station).  The	following Access Categories are	recognized:

	     AC_BE  (or	BE) best effort	delivery,
	     AC_BK  (or	BK) background traffic,
	     AC_VI  (or	VI) video traffic,
	     AC_VO  (or	VO) voice traffic.

	     AC	parameters are case-insensitive.  Traffic classification is
	     done in the operating system using	the vlan priority associated
	     with data frames or the ToS (Type of Service) indication in IP-
	     encapsulated frames.  If neither information is present, traffic
	     is	assigned to the	Best Effort (BE) category.

	     ack ac  Set the ACK policy	for QoS	transmissions by the local
		     station; this controls whether or not data	frames trans-
		     mitted by a station require an ACK	response from the
		     receiving station.	 To disable waiting for	an ACK use
		     -ack.  This parameter is applied only to the local	sta-
		     tion.

	     acm ac  Enable the	Admission Control Mandatory (ACM) mechanism
		     for transmissions by the local station.  To disable the
		     ACM use -acm.  On stations	in a BSS this parameter	is
		     read-only and indicates the setting received from the
		     access point.  NB:	ACM is not supported right now.

	     aifs ac count
		     Set the Arbitration Inter Frame Spacing (AIFS) channel
		     access parameter to use for transmissions by the local
		     station.  On stations in a	BSS this parameter is read-
		     only and indicates	the setting received from the access
		     point.

	     cwmin ac count
		     Set the CWmin channel access parameter to use for trans-
		     missions by the local station.  On	stations in a BSS this
		     parameter is read-only and	indicates the setting received
		     from the access point.

	     cwmax ac count
		     Set the CWmax channel access parameter to use for trans-
		     missions by the local station.  On	stations in a BSS this
		     parameter is read-only and	indicates the setting received
		     from the access point.

	     txoplimit ac limit
		     Set the Transmission Opportunity Limit channel access
		     parameter to use for transmissions	by the local station.
		     This parameter defines an interval	of time	when a WME
		     station has the right to initiate transmissions onto the
		     wireless medium.  On stations in a	BSS this parameter is
		     read-only and indicates the setting received from the
		     access point.

	     bss:aifs ac count
		     Set the AIFS channel access parameter to send to stations
		     in	a BSS.	This parameter is meaningful only when operat-
		     ing in ap mode.

	     bss:cwmin ac count
		     Set the CWmin channel access parameter to send to sta-
		     tions in a	BSS.  This parameter is	meaningful only	when
		     operating in ap mode.

	     bss:cwmax ac count
		     Set the CWmax channel access parameter to send to sta-
		     tions in a	BSS.  This parameter is	meaningful only	when
		     operating in ap mode.

	     bss:txoplimit ac limit
		     Set the TxOpLimit channel access parameter	to send	to
		     stations in a BSS.	 This parameter	is meaningful only
		     when operating in ap mode.

     The following parameters support an optional access control list feature
     available with some adaptors when operating in ap mode; see wlan_acl(4).
     This facility allows an access point to accept/deny association requests
     based on the MAC address of the station.  Note that this feature does not
     significantly enhance security as MAC address spoofing is easy to do.

     mac:add address
	     Add the specified MAC address to the database.  Depending on the
	     policy setting association	requests from the specified station
	     will be allowed or	denied.

     mac:allow
	     Set the ACL policy	to permit association only by stations regis-
	     tered in the database.

     mac:del address
	     Delete the	specified MAC address from the database.

     mac:deny
	     Set the ACL policy	to deny	association only by stations regis-
	     tered in the database.

     mac:kick address
	     Force the specified station to be deauthenticated.	 This typi-
	     cally is done to block a station after updating the address data-
	     base.

     mac:open
	     Set the ACL policy	to allow all stations to associate.

     mac:flush
	     Delete all	entries	in the database.

     The following parameters are for compatibility with other systems:

     nwid ssid
	     Another name for the ssid parameter.  Included for	NetBSD compat-
	     ibility.

     station name
	     Another name for the stationname parameter.  Included for BSD/OS
	     compatibility.

     wep     Another way of saying wepmode on.	Included for BSD/OS compati-
	     bility.

     -wep    Another way of saying wepmode off.	 Included for BSD/OS compati-
	     bility.

     nwkey key
	     Another way of saying: ``wepmode on weptxkey 1 wepkey 1:key
	     wepkey 2:-	wepkey 3:- wepkey 4:-''.  Included for NetBSD compati-
	     bility.

     nwkey n:k1,k2,k3,k4
	     Another way of saying ``wepmode on	weptxkey n wepkey 1:k1 wepkey
	     2:k2 wepkey 3:k3 wepkey 4:k4''.  Included for NetBSD compatibil-
	     ity.

     -nwkey  Another way of saying wepmode off.	 Included for NetBSD compati-
	     bility.

     The following parameters are specific to bridge interfaces:

     addm interface
	     Add the interface named by	interface as a member of the bridge.
	     The interface is put into promiscuous mode	so that	it can receive
	     every packet sent on the network.

     deletem interface
	     Remove the	interface named	by interface from the bridge.  Promis-
	     cuous mode	is disabled on the interface when it is	removed	from
	     the bridge.

     maxaddr size
	     Set the size of the bridge	address	cache to size.	The default is
	     100 entries.

     timeout seconds
	     Set the timeout of	address	cache entries to seconds seconds.  If
	     seconds is	zero, then address cache entries will not be expired.
	     The default is 240	seconds.

     addr    Display the addresses that	have been learned by the bridge.

     static interface-name address
	     Add a static entry	into the address cache pointing	to
	     interface-name.  Static entries are never aged out	of the cache
	     or	re-placed, even	if the address is seen on a different inter-
	     face.

     deladdr address
	     Delete address from the address cache.

     flush   Delete all	dynamically-learned addresses from the address cache.

     flushall
	     Delete all	addresses, including static addresses, from the
	     address cache.

     discover interface
	     Mark an interface as a ``discovering'' interface.	When the
	     bridge has	no address cache entry (either dynamic or static) for
	     the destination address of	a packet, the bridge will forward the
	     packet to all member interfaces marked as ``discovering''.	 This
	     is	the default for	all interfaces added to	a bridge.

     -discover interface
	     Clear the ``discovering'' attribute on a member interface.	 For
	     packets without the ``discovering'' attribute, the	only packets
	     forwarded on the interface	are broadcast or multicast packets and
	     packets for which the destination address is known	to be on the
	     interface's segment.

     learn interface
	     Mark an interface as a ``learning'' interface.  When a packet
	     arrives on	such an	interface, the source address of the packet is
	     entered into the address cache as being a destination address on
	     the interface's segment.  This is the default for all interfaces
	     added to a	bridge.

     -learn interface
	     Clear the ``learning'' attribute on a member interface.

     sticky interface
	     Mark an interface as a ``sticky'' interface.  Dynamically learned
	     address entries are treated at static once	entered	into the
	     cache.  Sticky entries are	never aged out of the cache or
	     replaced, even if the address is seen on a	different interface.

     -sticky interface
	     Clear the ``sticky'' attribute on a member	interface.

     private interface
	     Mark an interface as a ``private''	interface.  A private inter-
	     face does not forward any traffic to any other port that is also
	     a private interface.

     -private interface
	     Clear the ``private'' attribute on	a member interface.

     span interface
	     Add the interface named by	interface as a span port on the
	     bridge.  Span ports transmit a copy of every frame	received by
	     the bridge.  This is most useful for snooping a bridged network
	     passively on another host connected to one	of the span ports of
	     the bridge.

     -span interface
	     Delete the	interface named	by interface from the list of span
	     ports of the bridge.

     stp interface
	     Enable Spanning Tree protocol on interface.  The if_bridge(4)
	     driver has	support	for the	IEEE 802.1D Spanning Tree protocol
	     (STP).  Spanning Tree is used to detect and remove	loops in a
	     network topology.

     -stp interface
	     Disable Spanning Tree protocol on interface.  This	is the default
	     for all interfaces	added to a bridge.

     edge interface
	     Set interface as an edge port.  An	edge port connects directly to
	     end stations cannot create	bridging loops in the network, this
	     allows it to transition straight to forwarding.

     -edge interface
	     Disable edge status on interface.

     autoedge interface
	     Allow interface to	automatically detect edge status.  This	is the
	     default for all interfaces	added to a bridge.

     -autoedge interface
	     Disable automatic edge status on interface.

     ptp interface
	     Set the interface as a point to point link.  This is required for
	     straight transitions to forwarding	and should be enabled on a
	     direct link to another RSTP capable switch.

     -ptp interface
	     Disable point to point link status	on interface.  This should be
	     disabled for a half duplex	link and for an	interface connected to
	     a shared network segment, like a hub or a wireless	network.

     autoptp interface
	     Automatically detect the point to point status on interface by
	     checking the full duplex link status.  This is the	default	for
	     interfaces	added to the bridge.

     -autoptp interface
	     Disable automatic point to	point link detection on	interface.

     maxage seconds
	     Set the time that a Spanning Tree protocol	configuration is
	     valid.  The default is 20 seconds.	 The minimum is	6 seconds and
	     the maximum is 40 seconds.

     fwddelay seconds
	     Set the time that must pass before	an interface begins forwarding
	     packets when Spanning Tree	is enabled.  The default is 15 sec-
	     onds.  The	minimum	is 4 seconds and the maximum is	30 seconds.

     hellotime seconds
	     Set the time between broadcasting of Spanning Tree	protocol con-
	     figuration	messages.  The hello time may only be changed when
	     operating in legacy stp mode.  The	default	is 2 seconds.  The
	     minimum is	1 second and the maximum is 2 seconds.

     priority value
	     Set the bridge priority for Spanning Tree.	 The default is	32768.
	     The minimum is 0 and the maximum is 61440.

     proto value
	     Set the Spanning Tree protocol.  The default is rstp.  The	avail-
	     able options are stp and rstp.

     holdcnt value
	     Set the transmit hold count for Spanning Tree.  This is the num-
	     ber of packets transmitted	before being rate limited.  The
	     default is	6.  The	minimum	is 1 and the maximum is	10.

     ifpriority	interface value
	     Set the Spanning Tree priority of interface to value.  The
	     default is	128.  The minimum is 0 and the maximum is 240.

     ifpathcost	interface value
	     Set the Spanning Tree path	cost of	interface to value.  The
	     default is	calculated from	the link speed.	 To change a previ-
	     ously selected path cost back to automatic, set the cost to 0.
	     The minimum is 1 and the maximum is 200000000.

     ifmaxaddr interface size
	     Set the maximum number of hosts allowed from an interface,	pack-
	     ets with unknown source addresses are dropped until an existing
	     host cache	entry expires or is removed.  Set to 0 to disable.

     The following parameters are specific to lagg interfaces:

     laggport interface
	     Add the interface named by	interface as a port of the aggregation
	     interface.

     -laggport interface
	     Remove the	interface named	by interface from the aggregation
	     interface.

     laggproto proto
	     Set the aggregation protocol.  The	default	is failover.  The
	     available options are failover, fec, lacp,	loadbalance,
	     roundrobin	and none.

     The following parameters are specific to IP tunnel	interfaces, gif(4):

     tunnel src_addr dest_addr
	     Configure the physical source and destination address for IP tun-
	     nel interfaces.  The arguments src_addr and dest_addr are inter-
	     preted as the outer source/destination for	the encapsulating
	     IPv4/IPv6 header.

     -tunnel
	     Unconfigure the physical source and destination address for IP
	     tunnel interfaces previously configured with tunnel.

     deletetunnel
	     Another name for the -tunnel parameter.

     The following parameters are specific to GRE tunnel interfaces, gre(4):

     grekey key
	     Configure the GRE key to be used for outgoing packets.  Note that
	     gre(4) will always	accept GRE packets with	invalid	or absent
	     keys. This	command	will result in a four byte MTU reduction on
	     the interface.

     The following parameters are specific to pfsync(4)	interfaces:

     maxupd n
	     Set the maximum number of updates for a single state which	can be
	     collapsed into one.  This is an 8-bit number; the default value
	     is	128.

     The following parameters are specific to vlan(4) interfaces:

     vlan vlan_tag
	     Set the VLAN tag value to vlan_tag.  This value is	a 16-bit num-
	     ber which is used to create an 802.1Q VLAN	header for packets
	     sent from the vlan(4) interface.  Note that vlan and vlandev must
	     both be set at the	same time.

     vlandev iface
	     Associate the physical interface iface with a vlan(4) interface.
	     Packets transmitted through the vlan(4) interface will be
	     diverted to the specified physical	interface iface	with 802.1Q
	     VLAN encapsulation.  Packets with 802.1Q encapsulation received
	     by	the parent interface with the correct VLAN tag will be
	     diverted to the associated	vlan(4)	pseudo-interface.  The vlan(4)
	     interface is assigned a copy of the parent	interface's flags and
	     the parent's ethernet address.  The vlandev and vlan must both be
	     set at the	same time.  If the vlan(4) interface already has a
	     physical interface	associated with	it, this command will fail.
	     To	change the association to another physical interface, the
	     existing association must be cleared first.

	     Note: if the hardware tagging capability is set on	the parent
	     interface,	the vlan(4) pseudo interface's behavior	changes: the
	     vlan(4) interface recognizes that the parent interface supports
	     insertion and extraction of VLAN tags on its own (usually in
	     firmware) and that	it should pass packets to and from the parent
	     unaltered.

     -vlandev [iface]
	     If	the driver is a	vlan(4)	pseudo device, disassociate the	parent
	     interface from it.	 This breaks the link between the vlan(4)
	     interface and its parent, clears its VLAN tag, flags and its link
	     address and shuts the interface down.  The	iface argument is use-
	     less and hence deprecated.

     The following parameters are specific to carp(4) interfaces:

     advbase seconds
	     Specifies the base	of the advertisement interval in seconds.  The
	     acceptable	values are 1 to	255.  The default value	is 1.

     advskew interval
	     Specifies the skew	to add to the base advertisement interval to
	     make one host advertise slower than another host.	It is speci-
	     fied in 1/256 of seconds.	The acceptable values are 1 to 254.
	     The default value is 0.

     pass phrase
	     Set the authentication key	to phrase.

     vhid n  Set the virtual host ID.  This is a required setting.  Acceptable
	     values are	1 to 255.

     The ifconfig utility displays the current configuration for a network
     interface when no optional	parameters are supplied.  If a protocol	family
     is	specified, ifconfig will report	only the details specific to that pro-
     tocol family.

     If	the -m flag is passed before an	interface name,	ifconfig will display
     the capability list and all of the	supported media	for the	specified
     interface.	 If -L flag is supplied, address lifetime is displayed for
     IPv6 addresses, as	time offset string.

     Optionally, the -a	flag may be used instead of an interface name.	This
     flag instructs ifconfig to	display	information about all interfaces in
     the system.  The -d flag limits this to interfaces	that are down, and -u
     limits this to interfaces that are	up.  When no arguments are given, -a
     is	implied.

     The -l flag may be	used to	list all available interfaces on the system,
     with no other additional information.  Use	of this	flag is	mutually
     exclusive with all	other flags and	commands, except for -d	(only list
     interfaces	that are down) and -u (only list interfaces that are up).

     The -v flag may be	used to	get more verbose status	for an interface.

     The -C flag may be	used to	list all of the	interface cloners available on
     the system, with no additional information.  Use of this flag is mutually
     exclusive with all	other flags and	commands.

     The -k flag causes	keying information for the interface, if available, to
     be	printed.  For example, the values of 802.11 WEP	keys will be printed,
     if	accessible to the current user.	 This information is not printed by
     default, as it may	be considered sensitive.

     If	the network interface driver is	not present in the kernel then
     ifconfig will attempt to load it.	The -n flag disables this behavior.

     Only the super-user may modify the	configuration of a network interface.

NOTES
     The media selection system	is relatively new and only some	drivers	sup-
     port it (or have need for it).

EXAMPLES
     Assign the	IPv4 address 192.0.2.10, with a	network	mask of	255.255.255.0,
     to	the interface fxp0:
	   # ifconfig fxp0 inet	192.0.2.10 netmask 255.255.255.0

     Add the IPv4 address 192.0.2.45, with the CIDR network prefix /28,	to the
     interface ed0, using add as a synonym for the canonical form of the
     option alias:
	   # ifconfig ed0 inet 192.0.2.45/28 add

     Remove the	IPv4 address 192.0.2.45	from the interface ed0:
	   # ifconfig ed0 inet 192.0.2.45 -alias

     Add the IPv6 address 2001:DB8:DBDB::123/48	to the interface em0:
	   # ifconfig em0 inet6	2001:db8:bdbd::123 prefixlen 48	alias
     Note that lower case hexadecimal IPv6 addresses are acceptable.

     Remove the	IPv6 address added in the above	example, using the / character
     as	shorthand for the network prefix, and using delete as a	synonym	for
     the canonical form	of the option -alias:
	   # ifconfig em0 inet6	2001:db8:bdbd::123/48 delete

     Configure the interface xl0, to use 100baseTX, full duplex	Ethernet media
     options:
	   # ifconfig xl0 media	100baseTX mediaopt full-duplex

     Create the	software network interface gif1:
	   # ifconfig gif1 create

     Destroy the software network interface gif1:
	   # ifconfig gif1 destroy

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

SEE ALSO
     netstat(1), carp(4), netintro(4), pfsync(4), polling(4), vlan(4), rc(8),
     routed(8),	sysctl(8)

HISTORY
     The ifconfig utility appeared in 4.2BSD.

BUGS
     Basic IPv6	node operation requires	a link-local address on	each interface
     configured	for IPv6.  Normally, such an address is	automatically config-
     ured by the kernel	on each	interface added	to the system; this behaviour
     may be disabled by	setting	the sysctl MIB variable
     net.inet6.ip6.auto_linklocal to 0.

     If	you delete such	an address using ifconfig, the kernel may act very
     odd.  Do this at your own risk.

FreeBSD	9.2			 June 20, 2008			   FreeBSD 9.2

NAME | SYNOPSIS | DESCRIPTION | NOTES | EXAMPLES | DIAGNOSTICS | SEE ALSO | HISTORY | BUGS

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