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IFCONFIG(8)		    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	inter-
       face and/or configure network interface parameters.  The	ifconfig util-
       ity must	be used	at boot	time to	define the network address of each in-
       terface 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 spec-
	       ify an address like 192.168.0.1/16.

	       For the "inet6" family, it is also possible to specify the pre-
	       fix 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  fil-
	       ter  in	the  underlying	 ethernet  hardware is properly	repro-
	       grammed.

       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,
	       specifying the address family is	recommended.  The  address  or
	       protocol	 families  currently  supported	 are  "inet", "inet6",
	       "atalk",	"ipx", and "link".  The	default	if available is	"inet"
	       or otherwise "link".  "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 compati-
	       bility 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 ef-
	       fect 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 any-
	       cast 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  ad-
	       dresses	(default).   This is currently implemented for mapping
	       between DARPA Internet addresses	and IEEE 802  48-bit  MAC  ad-
	       dresses (Ethernet, 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
	       perform	normally,  sending  out	 requests  and	listening  for
	       replies.

       broadcast
	       (Inet  only.)   Specify	the address to use to represent	broad-
	       casts to	the network.  The default broadcast address is the ad-
	       dress 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.

       description value, descr	value
	       Specify	a  description	of the interface.  This	can be used to
	       label interfaces	in situations where they may otherwise be dif-
	       ficult to distinguish.

       -description, -descr
	       Clear the interface description.

       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.

       fib fib_number
	       Specify interface FIB.  A FIB fib_number	 is  assigned  to  all
	       frames  or  packets received on that interface.	The FIB	is not
	       inherited, e.g. vlans or	other sub-interfaces will use the  de-
	       fault  FIB (0) irrespective of the parent interface's FIB.  The
	       kernel needs to be tuned	to support more	than the  default  FIB
	       using  the  ROUTETABLES	kernel	configuration  option,	or the
	       net.fibs	tunable.

       ipdst   This is used to specify an Internet host	who is willing to  re-
	       ceive  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 net-
	       work 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  me-
	       dia type	of the interface to type.  Some	interfaces support the
	       mutually	exclusive use of one of	several	different physical me-
	       dia  connectors.	  For  example,	 a 10Mbit/s Ethernet interface
	       might support the use of	either AUI or twisted pair connectors.
	       Setting the media type to 10base5/AUI  would  change  the  cur-
	       rently  active  connector  to  the  AUI	port.	Setting	 it to
	       10baseT/UTP would activate twisted pair.	 Refer to  the	inter-
	       faces' 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
	       specified 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 com-
	       plete 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
	       specified 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	 reli-
	       ably support, the exact level of	offloading varies between dri-
	       vers.

       -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  fa-
	       cility  whereby	a machine in a low power state may be woken in
	       response	to a received packet.  There are three types of	 pack-
	       ets  that  may wake a system: ucast (directed solely to the ma-
	       chine's mac address), mcast (directed to	a broadcast or	multi-
	       cast  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	synonym	for enabling all available WOL mechanisms.  To
	       disable WOL use -wol.

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

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

       vnet jail
	       Move  the  interface  to	the jail(8), specified by name or JID.
	       If the jail has a virtual network  stack,  the  interface  will
	       disappear  from	the  current environment and become visible to
	       the jail.

       -vnet jail
	       Reclaim the interface from the jail(8), specified  by  name  or
	       JID.   If  the  jail has	a virtual network stack, the interface
	       will disappear from the jail, and become	visible	to the current
	       network environment.

       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 out-
	       put 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
	       compatibility.

       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	favor-
	       able; metrics are counted as additional hops to the destination
	       network or host.

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

       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 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  con-
	       tains 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  net-
	       work  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 subdivid-
	       ing  networks  into sub-networks.  The len must be integer, and
	       for syntactical reason it must be between 0 to 128.  It is  al-
	       most  always 64 under the current IPv6 assignment rule.	If the
	       parameter 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  informa-
	       tion.

       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
	       netmasks.

       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,
	       however,	 they  are  in general used to select special modes of
	       operation.  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-
	       initialized.

       The following parameters	are for	ICMPv6	Neighbor  Discovery  Protocol.
       Note that the address family keyword "inet6" is needed for them:

       accept_rtadv
	       Set a flag to enable accepting ICMPv6 Router Advertisement mes-
	       sages.	The sysctl(8) variable net.inet6.ip6.accept_rtadv con-
	       trols whether this flag is set by default or not.

       -accept_rtadv
	       Clear a flag accept_rtadv.

       no_radr
	       Set a flag to control whether routers from which	the system ac-
	       cepts Router Advertisement messages will	be added  to  the  De-
	       fault  Router  List or not.  When the accept_rtadv flag is dis-
	       abled,  this  flag  has	no  effect.   The  sysctl(8)  variable
	       net.inet6.ip6.no_radr  controls whether this flag is set	by de-
	       fault or	not.

       -no_radr
	       Clear a flag no_radr.

       auto_linklocal
	       Set a flag to perform automatic link-local  address  configura-
	       tion when the interface becomes available.  The sysctl(8) vari-
	       able net.inet6.ip6.auto_linklocal controls whether this flag is
	       set by default or not.

       -auto_linklocal
	       Clear a flag auto_linklocal.

       defaultif
	       Set  the	specified interface as the default route when there is
	       no default router.

       -defaultif
	       Clear a flag defaultif.

       ifdisabled
	       Set a flag to disable all of IPv6 network communications	on the
	       specified interface.  Note that if there	are already configured
	       IPv6 addresses on that interface, all of	 them  are  marked  as
	       "tentative"  and	 DAD  will  be	performed  when	 this  flag is
	       cleared.

       -ifdisabled
	       Clear a	flag  ifdisabled.   When  this	flag  is  cleared  and
	       auto_linklocal  flag  is	 enabled, automatic configuration of a
	       link-local address is performed.

       nud     Set a flag to enable Neighbor Unreachability Detection.

       -nud    Clear a flag nud.

       prefer_source
	       Set a flag to prefer addresses on the interface	as  candidates
	       of the source address for outgoing packets.

       -prefer_source
	       Clear a flag prefer_source.

       The  following  parameters are specific to cloning IEEE 802.11 wireless
       interfaces with the create request:

       wlandev device
	       Use device as the parent	for the	cloned device.

       wlanmode	mode
	       Specify the operating mode for this cloned device.  mode	is one
	       of sta, ahdemo (or adhoc-demo ),	ibss, (or  adhoc  ),  ap,  (or
	       hostap  ), wds, tdma, mesh, and monitor.	 The operating mode of
	       a cloned	interface cannot be changed.  The tdma mode  is	 actu-
	       ally  implemented as an adhoc-demo interface with special prop-
	       erties.

       wlanbssid bssid
	       The 802.11 mac address to use for  the  bssid.	This  must  be
	       specified at create time	for a legacy wds device.

       wlanaddr	address
	       The local mac address.  If this is not specified	then a mac ad-
	       dress  will  automatically  be  assigned	 to the	cloned device.
	       Typically this address is the same as the address of the	parent
	       device but if the bssid parameter is specified then the	driver
	       will craft a unique address for the device (if supported).

       wdslegacy
	       Mark  a wds device as operating in ``legacy mode''.  Legacy wds
	       devices have a fixed peer relationship and do not, for example,
	       roam if their peer stops	communicating.	For completeness a Dy-
	       namic WDS (DWDS)	interface may marked as	-wdslegacy.

       bssid   Request a unique	local mac address for the cloned device.  This
	       is only possible	if the device supports multiple	mac addresses.
	       To force	use of the parent's mac	address	use -bssid.

       beacons
	       Mark the	cloned interface as depending on hardware  support  to
	       track  received	beacons.   To have beacons tracked in software
	       use -beacons.  For hostap mode -beacons can also	be used	to in-
	       dicate no beacons should	be transmitted;	 this  can  be	useful
	       when  creating  a WDS configuration but wds interfaces can only
	       be created as companions	to an access point.

       The following parameters	are specific to	IEEE  802.11  wireless	inter-
       faces cloned with a create operation:

       ampdu   Enable  sending	and  receiving AMPDU frames when using 802.11n
	       (default).  The 802.11n specification states a  compliant  sta-
	       tion must be capable of receiving AMPDU frames but transmission
	       is  optional.   Use  -ampdu  to	disable	 all use of AMPDU with
	       802.11n.	 For testing and/or to	work  around  interoperability
	       problems	 one can use ampdutx and ampdurx to control use	of AM-
	       PDU in one direction.

       ampdudensity density
	       Set the	AMPDU  density	parameter  used	 when  operating  with
	       802.11n.	  This parameter controls the inter-packet gap for AM-
	       PDU frames.  The	sending	device normally	controls this  setting
	       but  a  receiving station may request wider gaps.  Legal	values
	       for density are 0, .25, .5, 1, 2, 4, 8, and 16  (microseconds).
	       A value of - is treated the same	as 0.

       ampdulimit limit
	       Set  the	 limit	on packet size for receiving AMPDU frames when
	       operating with 802.11n.	 Legal	values	for  limit  are	 8192,
	       16384,  32768,  and  65536  but	one  can also specify just the
	       unique prefix: 8, 16, 32, 64.  Note the sender  may  limit  the
	       size  of	 AMPDU frames to be less than the maximum specified by
	       the receiving station.

       amsdu   Enable sending and receiving AMSDU frames when  using  802.11n.
	       By  default  AMSDU is received but not transmitted.  Use	-amsdu
	       to disable all use of AMSDU with	802.11n.  For  testing	and/or
	       to  work	 around	 interoperability problems one can use amsdutx
	       and amsdurx to control use of AMSDU in one direction.

       amsdulimit limit
	       Set the limit on	packet size for	sending	 and  receiving	 AMSDU
	       frames when operating with 802.11n.  Legal values for limit are
	       7935  and  3839 (bytes).	 Note the sender may limit the size of
	       AMSDU frames to be less than the	maximum	specified by  the  re-
	       ceiving	station.   Note	 also that devices are not required to
	       support the 7935	limit, only 3839 is required by	the specifica-
	       tion and	the larger value may require more memory to  be	 dedi-
	       cated to	support	functionality that is rarely used.

       apbridge
	       When  operating	as an access point, pass packets between wire-
	       less 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
	       traffic is to be	processed with packet filtering.

       authmode	mode
	       Set the desired authentication  mode  in	 infrastructure	 mode.
	       Not  all	adapters 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 use-
	       ful  when  using	 an  authentication  service (a	supplicant for
	       client operation	or an authenticator when operating as  an  ac-
	       cess 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.	 Back-
	       ground 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 op-
	       eration.	 By default background scanning	is enabled if the  de-
	       vice  is	capable.  To disable background	scanning, use -bgscan.
	       Background  scanning  is	 controlled  by	 the  bgscanidle   and
	       bgscanintvl  parameters.	  Background  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 de-
	       fault a station must be idle at least 250 milliseconds before a
	       background 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
	       background  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  sta-
	       tion  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 capa-
	       bilities.   The	default	threshold is 7 consecutive missed bea-
	       cons; 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 operat-
	       ing as a	station	in a BSS network.  This	 overrides  any	 auto-
	       matic  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
	       technique  whereby the wireless medium is acquired once to send
	       multiple	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 specification and some devices that	do not support
	       QoS may still be	capable.  By default packet  bursting  is  en-
	       abled  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 chan-
	       nels is specified as a comma-separated list with	 each  element
	       in  the	list  representing 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 charac-
	       teristics 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 any, or -
	       will clear any desired channel and, if the device is marked up,
	       force a scan for	a channel to operate  on.   Alternatively  the
	       frequency,  in megahertz, may be	specified instead of the chan-
	       nel 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''	speci-
	       fies 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  channel),	20  (20MHz mostly for use in specifying	ht20),
	       and 40 (40MHz mostly for	use in specifying ht40).  In addition,
	       a 40MHz HT channel specification	may include  the  location  of
	       the extension channel by	appending ``+''	or ``-'' for above and
	       below,  respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide
	       HT operation with the center channel at frequency 2437 and  the
	       extension channel above.

       country name
	       Set  the	country	code to	use in calculating the regulatory con-
	       straints	for operation.	In particular  the  set	 of  available
	       channels,  how  the wireless device will	operation on the chan-
	       nels, and the maximum transmit power that  can  be  used	 on  a
	       channel	are defined by this setting.  Country/Region codes are
	       specified as a 2-character abbreviation defined by ISO 3166  or
	       using a longer, but possibly ambiguous, spelling; e.g. "ES" and
	       "Spain".	  The  set of country codes are	taken from /etc/regdo-
	       main.xml	and can	also be	viewed with the	``list countries'' re-
	       quest.  Note that not all devices support changing the  country
	       code  from  a default setting; typically	stored in EEPROM.  See
	       also regdomain, indoor, outdoor,	and anywhere.

       dfs     Enable  Dynamic	Frequency  Selection  (DFS)  as	 specified  in
	       802.11h.	  DFS  embodies	several	facilities including detection
	       of overlapping radar signals, dynamic transmit  power  control,
	       and  channel selection according	to a least-congested criteria.
	       DFS support is mandatory	for some 5Ghz frequencies  in  certain
	       locales	(e.g.  ETSI).	By default DFS is enabled according to
	       the regulatory definitions specified in /etc/regdomain.xml  and
	       the current country code, regdomain, and	channel.  Note the un-
	       derlying	 device	 (and driver) must support radar detection for
	       full DFS	support	to work.  To be	fully compliant	with the local
	       regulatory agency frequencies that require DFS  should  not  be
	       used  unless  it	 is fully supported.  Use -dfs to disable this
	       functionality for testing.

       dotd    Enable support for the 802.11d specification  (default).	  When
	       this support is enabled in station mode,	beacon frames that ad-
	       vertise	a country code different than the currently configured
	       country code will cause an event	to be dispatched to  user  ap-
	       plications.   This  event  can  be used by the station to adopt
	       that country code and operate according to the associated regu-
	       latory constraints.  When operating as  an  access  point  with
	       802.11d	enabled	the beacon and probe response frames transmit-
	       ted will	advertise the current regulatory domain	settings.   To
	       disable 802.11d use -dotd.

       doth    Enable  802.11h	support	 including  spectrum management.  When
	       802.11h is enabled beacon and probe response frames  will  have
	       the  SpectrumMgt	 bit set in the	capabilities field and country
	       and power constraint  information  elements  will  be  present.
	       802.11h support also includes handling Channel Switch Announce-
	       ments (CSA) which are a mechanism to coordinate channel changes
	       by  an  access point.  By default 802.11h is enabled if the de-
	       vice 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
	       number  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  be-
	       tween 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 iden-
	       tified on the channel all stations will automatically drop back
	       to normal operation.  By	default, Dynamic Turbo mode is not en-
	       abled,  even  if	 the  device is	capable.  Note that turbo mode
	       (dynamic	or static) is only allowed on some channels  depending
	       on  the	regulatory  constraints;  use the list chan command to
	       identify	the channels where turbo mode may be used.  To disable
	       Dynamic Turbo mode use -dturbo.

       dwds    Enable Dynamic WDS (DWDS) support.  DWDS	is a facility by which
	       4-address traffic can be	carried	between	stations operating  in
	       infrastructure  mode.   A station first associates to an	access
	       point and authenticates using  normal  procedures  (e.g.	 WPA).
	       Then  4-address frames are passed to carry traffic for stations
	       operating on either side	of the wireless	 link.	 DWDS  extends
	       the normal WDS mechanism	by leveraging existing security	proto-
	       cols and	eliminating static binding.

	       When  DWDS  is  enabled on an access point 4-address frames re-
	       ceived from an authorized station will generate a  ``DWDS  dis-
	       covery''	event to user applications.  This event	should be used
	       to  create  a WDS interface that	is bound to the	remote station
	       (and usually plumbed into a bridge).  Once the WDS interface is
	       up and running 4-address	traffic	then logically	flows  through
	       that interface.

	       When  DWDS  is enabled on a station, traffic with a destination
	       address different from the peer station are encapsulated	 in  a
	       4-address  frame	 and  transmitted  to the peer.	 All 4-address
	       traffic uses the	security information  of  the  stations	 (e.g.
	       cryptographic keys).  A station is associated using 802.11n fa-
	       cilities	may transport 4-address	traffic	using these same mech-
	       anisms; this depends on available resources and capabilities of
	       the  device.   The  DWDS	 implementation	guards against layer 2
	       routing loops of	multicast traffic.

       ff      Enable the use of Atheros Fast Frames when  communicating  with
	       another Fast Frames-capable station.  Fast Frames are an	encap-
	       sulation	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  de-
	       capsulate  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	 capa-
	       ble.  To	explicitly disable fast	frames,	use -ff.

       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	adapters 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.

       ht      Enable use of High Throughput  (HT)  when  using	 802.11n  (de-
	       fault).	 The 802.11n specification includes mechanisms for op-
	       eration on 20MHz	and 40MHz wide channels	using  different  sig-
	       nalling	mechanisms  than  specified  in	 802.11b, 802.11g, and
	       802.11a.	 Stations negotiate use	of  these  facilities,	termed
	       HT20  and  HT40,	 when  they  associate.	 To disable all	use of
	       802.11n use -ht.	 To disable use	of HT20	(e.g.  to  force  only
	       HT40 use) use -ht20.  To	disable	use of HT40 use	-ht40.

	       HT  configuration  is  used  to ``auto promote''	operation when
	       several choices are available.  For example, if a station asso-
	       ciates to an 11n-capable	access point it	controls  whether  the
	       station	uses legacy operation, HT20, or	HT40.  When an 11n-ca-
	       pable device is setup as	an access point	and Auto  Channel  Se-
	       lection	is used	to locate a channel to operate on, HT configu-
	       ration controls whether legacy,	HT20,  or  HT40	 operation  is
	       setup on	the selected channel.  If a fixed channel is specified
	       for a station then HT configuration can be given	as part	of the
	       channel	specification; e.g. 6:ht/20 to setup HT20 operation on
	       channel 6.

       htcompat
	       Enable use of compatibility  support  for  pre-802.11n  devices
	       (default).   The	 802.11n  protocol  specification went through
	       several incompatible iterations.	 Some vendors implemented  11n
	       support to older	specifications that will not interoperate with
	       a  purely 11n-compliant station.	 In particular the information
	       elements	included in management frames for old devices are dif-
	       ferent.	When compatibility support is  enabled	both  standard
	       and  compatible data will be provided.  Stations	that associate
	       using the compatibility mechanisms are flagged in ``list	sta''.
	       To disable compatibility	support	use -htcompat.

       htprotmode technique
	       For  interfaces	operating  in  802.11n,	 use   the   specified
	       technique  for  protecting  HT frames in	a mixed	legacy/HT net-
	       work.  The set of valid techniques is off,  and	rts  (RTS/CTS,
	       default).  Technique names are case insensitive.

       inact   Enable  inactivity processing for stations associated to	an ac-
	       cess point (default).  When operating as	an  access  point  the
	       802.11  layer monitors the activity of each associated station.
	       When a station is inactive for 5	minutes	it will	 send  several
	       ``probe frames''	to see if the station is still present.	 If no
	       response	 is received then the station is deauthenticated.  Ap-
	       plications that prefer to handle	this work can disable this fa-
	       cility by using -inact.

       indoor  Set the location	to use in calculating regulatory  constraints.
	       The  location  is  also advertised in beacon and	probe response
	       frames when 802.11d is enabled with dotd.   See	also  outdoor,
	       anywhere, country, and regdomain.

       list active
	       Display	the list of channels available for use taking into ac-
	       count 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  con-
	       straint	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 informa-
	       tion.  By default a compacted list of channels is displayed; if
	       the -v option is	specified then all channels are	shown.

       list countries
	       Display the set of country codes	and  regulatory	 domains  that
	       can be used in regulatory configuration.

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

       list mesh
	       Displays	the mesh routing table,	used for forwarding packets on
	       a mesh network.

       list regdomain
	       Display the current regulatory settings including the available
	       channels	and transmit power caps.

       list roam
	       Display the parameters that govern roaming operation.

       list txparam
	       Display the parameters that govern transmit operation.

       list txpower
	       Display the transmit power caps for each	channel.

       list scan
	       Display	the  access  points and/or ad-hoc neighbors located in
	       the vicinity.  This information may be updated automatically by
	       the adapter with	a scan request or through background scanning.
	       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
		    HT transmit	rates.	If a  `+'  follows  immediately	 after
		    then  the  station	associated using deprecated mechanisms
		    supported only when	htcompat is enabled.

	       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.

	       S    Short Preamble.  Indicates that the	station	is doing short
		    preamble to	optionally improve throughput performance with
		    802.11g and	802.11b.

	       T    Transitional Security Network (TSN).  Indicates  that  the
		    station associated using TSN; see also tsn below.

	       W    Wi-Fi  Protected  Setup (WPS).  Indicates that the station
		    associated using WPS.

	       By default interesting information elements captured  from  the
	       neighboring  stations  are  displayed  at  the end of each row.
	       Possible	elements include:  WME	(station  supports  WME),  WPA
	       (station	 supports  WPA), WPS (station supports WPS), RSN (sta-
	       tion supports 802.11i/RSN), HTCAP (station supports  802.11n/HT
	       communication),	ATH  (station supports Atheros protocol	exten-
	       sions), VEN (station supports  unknown  vendor-specific	exten-
	       sions).	 If  the  -v flag is used all the information elements
	       and their contents will be shown.  Specifying the -v flag  also
	       enables	display	of long	SSIDs.	The list ap command 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
	       stations	 identified  as	neighbors in the IBSS.	When operating
	       in mesh mode display stations identified	as  neighbors  in  the
	       MBSS.  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
		    HT	transmit  rates.   If  a `+' follows immediately after
		    then the station associated	 using	deprecated  mechanisms
		    supported only when	htcompat is enabled.

	       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.

	       S    Short Preamble.  Indicates that the	station	is doing short
		    preamble to	optionally improve throughput performance with
		    802.11g and	802.11b.

	       T    Transitional  Security  Network (TSN).  Indicates that the
		    station associated using TSN; see also tsn below.

	       W    Wi-Fi Protected Setup (WPS).  Indicates that  the  station
		    associated using WPS.

	       By  default  information	elements received from associated sta-
	       tions are displayed in a	short form; the	-v  flag  causes  this
	       information to be displayed symbolically.

       list wme
	       Display the current channel parameters to use when operating in
	       WME  mode.  If the -v option is specified then both channel and
	       BSS parameters are displayed for	each AC	(first	channel,  then
	       BSS).  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  dis-
	       abled.	See  the description of	the wme	directive for informa-
	       tion on the various parameters.

       maxretry	count
	       Set the maximum number of  tries	 to  use  in  sending  unicast
	       frames.	The default setting is 6 but drivers may override this
	       with a value they choose.

       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
	       conditions; if an invalid rate is specified drivers are free to
	       chose an	appropriate rate.

       mgtrate rate
	       Set the rate for	transmitting management	and/or control frames.
	       Rates are specified as megabits/second in decimal; e.g. 5.5 for
	       5.5 Mb/s.

       outdoor
	       Set  the	location to use	in calculating regulatory constraints.
	       The location is also advertised in beacon  and  probe  response
	       frames  when  802.11d is	enabled	with dotd.  See	also anywhere,
	       country,	indoor,	and regdomain.

       powersave
	       Enable powersave	operation.  When operating as  a  client,  the
	       station will conserve power by periodically turning off the ra-
	       dio 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  net-
	       work.   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
	       permitted  to  associate).  To allow both 11g and 11b-only sta-
	       tions to	associate, use -pureg.

       puren   When operating as an access point in 802.11n  mode  allow  only
	       HT-capable  stations to associate (legacy stations are not per-
	       mitted to associate).  To allow both HT and legacy stations  to
	       associate, use -puren.

       regdomain sku
	       Set  the	regulatory domain to use in calculating	the regulatory
	       constraints for operation.  In particular the set of  available
	       channels,  how  the wireless device will	operation on the chan-
	       nels, and the maximum transmit power that  can  be  used	 on  a
	       channel	are  defined by	this setting.  Regdomain codes (SKU's)
	       are taken from /etc/regdomain.xml and can also be  viewed  with
	       the ``list countries'' request.	Note that not all devices sup-
	       port  changing  the regdomain from a default setting; typically
	       stored in EEPROM.   See	also  country,	indoor,	 outdoor,  and
	       anywhere.

       rifs    Enable  use of Reduced InterFrame Spacing (RIFS)	when operating
	       in 802.11n on an	HT channel.  Note that RIFS must be  supported
	       by  both	 the  station  and access point	for it to be used.  To
	       disable RIFS use	-rifs.

       roam:rate rate
	       Set the threshold for controlling roaming when operating	 in  a
	       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 ac-
	       cess point is available and switch over	to  it.	  The  current
	       scan  cache  contents are used if they are considered valid ac-
	       cording to the scanvalid	parameter; otherwise a background scan
	       operation is triggered before any selection occurs.  Each chan-
	       nel type	has a separate rate threshold; the default values are:
	       12 Mb/s (11a), 2	Mb/s (11b), 2 Mb/s (11g), MCS 1	(11na, 11ng).

       roam:rssi rssi
	       Set the threshold for controlling roaming when operating	 in  a
	       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  ac-
	       cess  point  is	available  and switch over to it.  The current
	       scan cache contents are used if they are	considered  valid  ac-
	       cording to the scanvalid	parameter; otherwise a background scan
	       operation is triggered before any selection occurs.  Each chan-
	       nel  type has a separate	rssi threshold;	the default values are
	       all 7 dBm.

       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 hard-
	       ware device to decide), auto (handle either in  the  device  or
	       the operating system--as	appropriate), manual (do nothing until
	       explicitly instructed).	By default, the	device is left to han-
	       dle this	if it is capable; otherwise, the operating system will
	       automatically  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.

       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	adapters support setting the RTS threshold.

       scan    Initiate	 a  scan  of neighboring stations, wait	for it to com-
	       plete, and display all stations found.  Only the	super-user can
	       initiate	a scan.	 See list scan for information on the display.
	       By default a background scan is done;  otherwise	 a  foreground
	       scan  is	 done  and  the	station	may roam to a different	access
	       point.  The list	scan request can be used to show  recent  scan
	       results without initiating a new	scan.

       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 an-
	       other access point may trigger unnecessary background scan  op-
	       erations.

       shortgi
	       Enable use of Short Guard Interval when operating in 802.11n on
	       an  HT  channel.	  NB:  this currently enables Short GI on both
	       HT40 and	HT20 channels.	To disable Short GI use	-shortgi.

       smps    Enable use of Static Spatial  Multiplexing  Power  Save	(SMPS)
	       when  operating	in  802.11n.   A station operating with	Static
	       SMPS maintains only a single receive  chain  active  (this  can
	       significantly  reduce  power consumption).  To disable SMPS use
	       -smps.

       smpsdyn
	       Enable use of Dynamic Spatial Multiplexing  Power  Save	(SMPS)
	       when  operating	in  802.11n.  A	station	operating with Dynamic
	       SMPS maintains only a single receive chain active but  switches
	       to  multiple receive chains when	it receives an RTS frame (this
	       can significantly reduce	power consumption).   Note  that  sta-
	       tions  cannot  distinguish  between  RTS/CTS intended to	enable
	       multiple	receive	chains and those used for other	purposes.   To
	       disable SMPS use	-smps.

       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 spec-
	       ified as	either a normal	string or in hexadecimal when preceded
	       by  `0x'.   Additionally, the SSID may be cleared by setting it
	       to `-'.

       tdmaslot	slot
	       When operating with TDMA, use the specified slot	configuration.
	       The slot	is a number between 0 and the maximum number of	 slots
	       in the BSS.  Note that a	station	configured as slot 0 is	a mas-
	       ter  and	will broadcast beacon frames advertising the BSS; sta-
	       tions configured	to use other slots will	always scan to	locate
	       a master	before they ever transmit.  By default tdmaslot	is set
	       to 1.

       tdmaslotcnt cnt
	       When operating with TDMA, setup a BSS with cnt slots.  The slot
	       count  may  be  at  most	8.  The	current	implementation is only
	       tested with two stations	(i.e. point  to	 point	applications).
	       This setting is only meaningful when a station is configured as
	       slot  0;	 other	stations  adopt	this setting from the BSS they
	       join.  By default tdmaslotcnt is	set to 2.

       tdmaslotlen len
	       When operating with TDMA, setup a BSS such  that	 each  station
	       has  a  slot len	microseconds long.  The	slot length must be at
	       least 150 microseconds (1/8 TU) and no more than	 65  millisec-
	       onds.   Note that setting too small a slot length may result in
	       poor channel bandwidth utilization due to factors such as timer
	       granularity and guard time.  This setting  is  only  meaningful
	       when  a	station	 is configured as slot 0; other	stations adopt
	       this setting from the BSS they join.  By	default	tdmaslotlen is
	       set to 10 milliseconds.

       tdmabintval intval
	       When operating with TDMA, setup a BSS  such  that  beacons  are
	       transmitted  every  intval  superframes to synchronize the TDMA
	       slot timing.  A superframe is defined as	the  number  of	 slots
	       times  the  slot	 length; e.g.  a BSS with two slots of 10 mil-
	       liseconds has a 20 millisecond superframe.  The beacon interval
	       may not be zero.	 A lower setting  of  tdmabintval  causes  the
	       timers  to  be  resynchronized  more often; this	can be help if
	       significant timer drift is observed.  By	default	tdmabintval is
	       set to 5.

       tsn     When operating as an access point with WPA/802.11i allow	legacy
	       stations	to associate using static key WEP and open authentica-
	       tion.  To disallow legacy station use of	WEP, use -tsn.

       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 adapters	support	changing the transmit power.

       ucastrate rate
	       Set  a  fixed  rate for transmitting unicast 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 conditions;
	       if an invalid rate is specified drivers are free	 to  chose  an
	       appropriate rate.

       wepmode mode
	       Set  the	desired	WEP mode.  Not all adapters 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  adapters,	on means that the access point must only allow
	       encrypted connections.  On other	adapters, on is	generally  an-
	       other 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 on 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	 maxi-
	       mum  portability, hex keys are recommended; the mapping of text
	       keys to WEP encryption is usually driver-specific.  In particu-
	       lar,  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 adapters
	       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 adaptor 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
	       traffic.

       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  re-
	       altime  and multimedia data.  To	disable	WME support, use -wme.
	       Another name for	this parameter is wmm.

	       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
	       latter 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, traf-
	       fic 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
		       transmitted 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
		       station.

	       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
		       transmissions by	the local station.  On stations	 in  a
		       BSS  this parameter is read-only	and indicates the set-
		       ting received from the access point.

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

	       txoplimit ac limit
		       Set  the	 Transmission Opportunity Limit	channel	access
		       parameter to use	for transmissions by  the  local  sta-
		       tion.   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  re-
		       ceived from the access point.

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

       wps     Enable Wireless Privacy Subscriber support.  Note that WPS sup-
	       port requires a WPS-capable supplicant.	To disable this	 func-
	       tion use	-wps.

       The  following  parameters support an optional access control list fea-
       ture available with some	 adapters  when	 operating  in	ap  mode;  see
       wlan_acl(4).  This facility allows an access point to accept/deny asso-
       ciation	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 sta-
	       tion will be allowed or denied.

       mac:allow
	       Set the ACL policy to permit association	only by	stations  reg-
	       istered 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
	       database.

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

       mac:flush
	       Delete all entries in the database.

       mac:radius
	       Set the ACL policy to permit association	only by	 stations  ap-
	       proved by a RADIUS server.  Note	that this feature requires the
	       hostapd(8)  program  be	configured to do the right thing as it
	       handles the RADIUS processing (and  marks  stations  as	autho-
	       rized).

       The  following parameters are related to	a wireless interface operating
       in mesh mode:

       meshid meshid
	       Set the desired Mesh Identifier.	 The Mesh ID is	a string up to
	       32 characters in	length.	 A mesh	interface  must	 have  a  Mesh
	       Identifier specified to reach an	operational state.

       meshttl ttl
	       Set  the	 desired  ``time to live'' for mesh forwarded packets;
	       this is the number of hops a packet may be forwarded before  it
	       is discarded.  The default setting for meshttl is 31.

       meshpeering
	       Enable  or  disable  peering with neighbor mesh stations.  Sta-
	       tions must peer before any data packets can be  exchanged.   By
	       default meshpeering is enabled.

       meshforward
	       Enable  or  disable forwarding packets by a mesh	interface.  By
	       default meshforward is enabled.

       meshmetric protocol
	       Set the specified protocol as the link metric protocol used  on
	       a  mesh	network.  The default protocol is called AIRTIME.  The
	       mesh interface will restart after changing this setting.

       meshpath	protocol
	       Set the specified protocol as the path selection	protocol  used
	       on  a  mesh network.  The only available	protocol at the	moment
	       is called HWMP (Hybrid Wireless Mesh Protocol).	The  mesh  in-
	       terface will restart after changing this	setting.

       hwmprootmode mode
	       Stations	on a mesh network can operate as ``root	nodes.''  Root
	       nodes  try  to find paths to all	mesh nodes and advertise them-
	       selves regularly.  When there is	a root mesh node on a network,
	       other mesh nodes	can setup paths	between	themselves faster  be-
	       cause they can use the root node	to find	the destination.  This
	       path may	not be the best, but on-demand routing will eventually
	       find the	best path.  The	following modes	are recognized:

	       DISABLED	  Disable root mode.
	       NORMAL	  Send	broadcast  path	 requests  every  two seconds.
			  Nodes	on the mesh without a path to this  root  mesh
			  station with try to discover a path to us.
	       PROACTIVE  Send	broadcast  path	requests every two seconds and
			  every	node must reply	with with a path reply even if
			  it already has a path	to this	root mesh station.
	       RANN	  Send	broadcast  root	 announcement  (RANN)  frames.
			  Nodes	 on  the mesh without a	path to	this root mesh
			  station with try to discover a path to us.
	       By default hwmprootmode is set to DISABLED.

       hwmpmaxhops cnt
	       Set the maximum number of hops allowed in an HMWP path to  cnt.
	       The default setting for hwmpmaxhops is 31.

       The following parameters	are for	compatibility with other systems:

       nwid ssid
	       Another	name for the ssid parameter.  Included for NetBSD com-
	       patibility.

       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.	 One  can also use station 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 compat-
	       ibility.

       nwkey key
	       Another way of saying: "wepmode	on  weptxkey  1	 wepkey	 1:key
	       wepkey 2:- wepkey 3:- wepkey 4:-".  Included for	NetBSD compat-
	       ibility.

       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 compat-
	       ibility.

       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 re-
	       ceive every packet sent on the network.

       deletem interface
	       Remove the  interface  named  by	 interface  from  the  bridge.
	       Promiscuous  mode  is  disabled on the interface	when it	is re-
	       moved 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  ex-
	       pired.  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 ad-
	       dress 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  for-
	       ward   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 ar-
	       rives 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	inter-
	       faces 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 re-
	       placed, 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  de-
	       fault 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  con-
	       nected  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 forward-
	       ing packets when	Spanning Tree is enabled.  The default	is  15
	       seconds.	  The  minimum is 4 seconds and	the maximum is 30 sec-
	       onds.

       hellotime seconds
	       Set the time between broadcasting  of  Spanning	Tree  protocol
	       configuration  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
	       available options are stp and rstp.

       holdcnt value
	       Set  the	 transmit  hold	 count for Spanning Tree.  This	is the
	       number 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 de-
	       fault 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 de-
	       fault 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,
	       packets	with unknown source addresses are dropped until	an ex-
	       isting 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 aggrega-
	       tion 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
	       tunnel interfaces.  The arguments src_addr  and	dest_addr  are
	       interpreted as the outer	source/destination for the encapsulat-
	       ing 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.

       accept_rev_ethip_ver
	       Set a flag to accept both correct EtherIP packets and ones with
	       reversed	version	field.	Enabled	by default.  This is for back-
	       ward compatibility with FreeBSD 6.1, 6.2, 6.3, 7.0, and 7.1.

       -accept_rev_ethip_ver
	       Clear a flag accept_rev_ethip_ver.

       send_rev_ethip_ver
	       Set a flag to send EtherIP packets with reversed	version	 field
	       intentionally.  Disabled	by default.  This is for backward com-
	       patibility with FreeBSD 6.1, 6.2, 6.3, 7.0, and 7.1.

       -send_rev_ethip_ver
	       Clear a flag send_rev_ethip_ver.

       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	reduc-
	       tion 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
	       number which is used to create an 802.1Q	VLAN header for	 pack-
	       ets  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)	inter-
	       face.   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  com-
	       mand  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  par-
	       ent unaltered.

       -vlandev	[iface]
	       If the driver is	a vlan(4) pseudo device, disassociate the par-
	       ent  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 useless 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.   Accept-
	       able 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 fam-
       ily is specified, ifconfig will report only  the	 details  specific  to
       that protocol family.

       If  the	-m flag	is passed before an interface name, ifconfig will dis-
       play the	capability list	and all	of the supported media for the	speci-
       fied  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 ex-
       clusive with all	other flags and	commands, except for -d	(only list in-
       terfaces	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 mu-
       tually 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	inter-
       face.

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

       Enable IPv6 functionality of the	interface:
	     # ifconfig	em0 inet6 -ifdisabled

       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 / charac-
       ter 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 me-
       dia options:
	     # ifconfig	xl0 media 100baseTX mediaopt full-duplex

       Label the em0 interface as an uplink:
	     # ifconfig	em0 description	"Uplink	to Gigabit Switch 2"

       Create the software network interface gif1:
	     # ifconfig	gif1 create

       Destroy the software network interface gif1:
	     # ifconfig	gif1 destroy

       Display available wireless networks using wlan0:
	     # ifconfig	wlan0 list scan

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.

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

HISTORY
       The ifconfig utility appeared in	4.2BSD.

BUGS
       Basic IPv6 node operation requires a link-local address on each	inter-
       face  configured	 for IPv6.  Normally, such an address is automatically
       configured by the kernel	on each	interface added	to the system  or  en-
       abled;  this  behavior  may  be	disabled by setting per-interface flag
       -auto_linklocal.	 The default value of this flag	is 1 and can  be  dis-
       abled by	using the sysctl MIB variable net.inet6.ip6.auto_linklocal.

       Do  not	configure  IPv6	 addresses with	no link-local address by using
       ifconfig.  It can result	in unexpected behaviors	of the kernel.

FreeBSD	9.0		      September	13, 2011		   IFCONFIG(8)

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