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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 the ``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
             transmissions 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 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
             example, ``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
             compatibility 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
             (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 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.

     description value, descr value
             Specify a description of the interface.  This can be used to
             label interfaces in situations where they may otherwise be
             difficult 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
             default 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
             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
             mutually 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.
             Setting 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
             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 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
             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
             interface.  Some drivers may not be able to enable these flags
             independently 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
             interface.  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
             facility 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
             synonym for enabling all available WOL mechanisms.  To disable
             WOL use -wol.

     vlanmtu, vlanhwtag, vlanhwfilter, vlanhwcsum, vlanhwtso
             If the driver offers user-configurable VLAN support, enable
             reception of extended frames, tag processing in hardware, frame
             filtering in hardware, checksum offloading, 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
             interface, 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
             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 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
             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 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
             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 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
             netmasks.

     remove  Another name for the -alias parameter.  Introduced for
             compatibility 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
             interface 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 Neightbor Discovery Protocol:

     accept_rtadv
             Set a flag to enable accepting ICMPv6 Router Advertisement
             messages.

     -accept_rtadv
             Clear a flag accept_rtadv.

     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.

     -ifdisabled
             Clear a flag ifdisabled.

     nud     Set a flag to enable Neighbor Unreachability Detection.

     -nud    Clear a flag nud.

     prefer_source
             Set a flag to prefer addesses 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 actually
             implemented as an adhoc-demo interface with special properties.

     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
             address 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
             Dynamic 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 indicate
             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 interfaces
     cloned with a create operation:

     ampdu   Enable sending and receiving AMPDU frames when using 802.11n
             (default).  The 802.11n specification states a compliant station
             must be capable of receiving AMPDU frames but transmision 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 AMPDU in one
             direction.

     ampdudensity density
             Set the AMPDU density parameter used when operating with 802.11n.
             This parameter controls the inter-packet gap for AMPDU 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
             receiving station.  Note also that devices are not required to
             support the 7935 limit, only 3839 is required by the
             specification and the larger value may require more memory to be
             dedicated to support functionality that is rarely used.

     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
             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 useful when
             using an authentication service (a supplicant for client
             operation or an authenticator when operating as an access point).
             Modes are case insensitive.

     bgscan  Enable background scanning when operating as a station.
             Background 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
             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 default 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 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
             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 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
             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 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 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 channel number.

             When there are several ways to use a channel the channel
             number/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
             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
             constraints for operation.  In particular the set of available
             channels, how the wireless device will operation on the channels,
             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/regdomain.xml and can
             also be viewed with the ``list countries'' request.  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
             curent country code, regdomain, and channel.  Note the underlying
             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
             advertise a country code different than the currently configured
             country code will cause an event to be dispatched to user
             applications.  This event can be used by the station to adopt
             that country code and operate according to the associated
             regulatory constraints.  When operating as an access point with
             802.11d enabled the beacon and probe response frames transmitted
             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 Announcements (CSA)
             which are a mechanism to coordinate channel changes by 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
             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 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
             operation.  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 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 protocols
             and eliminating static binding.

             When DWDS is enabled on an access point 4-address frames received
             from an authorized station will generate a ``DWDS discovery''
             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
             facilities may transport 4-address traffic using these same
             mechanisms; 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
             encapsulation 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 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 (default).
             The 802.11n specification includes mechanisms for operation on
             20MHz and 40MHz wide channels using different signalling
             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
             associates to an 11n-capable access point it controls whether the
             station uses legacy operation, HT20, or HT40.  When an 11n-
             capable device is setup as an access point and Auto Channel
             Selection is used to locate a channel to operate on, HT
             configuration 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
             different.  When compatibility support is enabled both standard
             and compatible data will be provided.  Stations that associate
             using the compatiblity mechanisms are flagged in ``list sta''.
             To disable compatiblity support use -htcompat.

     htprotmode technique
             For interfaces operating in 802.11n, use the specified technique
             for protecting HT frames in a mixed legacy/HT network.  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 access
             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.  Applications
             that prefer to handle this work can disable this facility 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
             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
             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 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
             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 (station
             supports 802.11i/RSN), HTCAP (station supports 802.11n/HT
             communication), ATH (station supports Atheros protocol
             extensions), VEN (station supports unknown vendor-specific
             extensions).  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 stations
             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 disabled.  See
             the description of the wme directive for information 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 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
             permitted to associate).  To allow both 11g and 11b-only stations
             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 permitted
             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 channels,
             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 support 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 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.  Each channel 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 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.  Each channel 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 hardware
             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 handle
             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 complete,
             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
             operation 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.

     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 stations
             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
             specified 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 master
             and will broadcast beacon frames advertising the BSS; stations
             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 milliseconds.  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 milliseconds 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
             authentication.  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
             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 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
             available, for the specified interface.  WME is a subset of the
             IEEE 802.11e standard to support the efficient communication of
             realtime 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, 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
                     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 setting
                     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 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
                     operating in ap mode.

             bss:cwmin ac count
                     Set the CWmin channel access parameter to send to
                     stations 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
                     stations 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
             support requires a WPS-capable supplicant.  To disable this
             function use -wps.

     The following parameters support an optional access control list feature
     available with some adapters 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
             registered 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
             registered in the database.

     mac:kick address
             Force the specified station to be deauthenticated.  This
             typically 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
             approved 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 authorized).

     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.  Stations
             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 interface
             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
             themselves regularly.  When there is a root mesh node on a
             network, other mesh nodes can setup paths between themselves
             faster because 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 annoucement (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
             compatibility.

     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
             compatibility.

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

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

     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
             compatibility.

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

     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.
             Promiscuous 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
             2000 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 1200 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
             interface.

     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
             interface 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
             seconds.  The minimum is 4 seconds and the maximum is 30 seconds.

     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
             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
             previously 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
             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.

     lagghash option[,option]
             Set the packet layers to hash for aggregation protocols which
             load balance.  The default is ``l2,l3,l4''.  The options can be
             combined using commas.

             l2      src/dst mac address and optional vlan number.
             l3      src/dst address for IPv4 or IPv6.
             l4      src/dst port for TCP/UDP/SCTP.

     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 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.

     accept_rev_ethip_ver
             Set a flag to acccept both correct EtherIP packets and ones with
             reversed version field.  Enabled by default.  This is for
             backward 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
             compatibility 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 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
             number 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
             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
             specified 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.

     state state
             Force the interface into state state.  Valid states are INIT,
             BACKUP, and MASTER. Note that manually setting the state to INIT
             is ignored by carp(4).  This state is set automatically when the
             underlying interface is down.

     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
     protocol 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.

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

     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 requested
     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),
     devd.conf(5), devd(8), 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 interface
     configured for IPv6.  Normally, such an address is automatically
     configured 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 11.0-PRERELEASE        November 7, 2012        FreeBSD 11.0-PRERELEASE

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

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