IFCONFIG(8)

NAME
ifconfig - configure network interface parameters

SYNOPSIS
ifconfig [-f type:format[,type:format]] [-L] [-k] [-m] [-n] interface [create] [address_family] [ address [dest_address]] [parameters]
ifconfig [-n] interface destroy
ifconfig -a [-G nogroup] [-L] [ -d | -u] [-g matchgroup] [-m] [-v] [address_family]
ifconfig -l [ -d | -u] [address_family]
ifconfig [-L] [ -d | -u] [-k] [-m] [-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.

ifconfig 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 no parameters are provided, a summary of all interfaces is provided.

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

The following options are available:

-a  Display information about all interfaces on the system.

    The -a flag may be used instead of the interface argument. This is the default, if no parameters are given to ifconfig.

-C  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.

-d  Display only the interfaces that are down.

-f  type:format [,type:format ...] Control the output formats of ifconfig. The format is specified as a comma-separated list of type:format pairs. This option can be supplied multiple times. Alternatively, the output formats can be specified via the IFCONFIG_FORMAT environment variable.

    The supported types and their associated format strings are:

    addr
        Adjust the display of inet and inet6 addresses:

        default
            Default format, i.e., numeric
        fqdn
            Fully qualified domain names (FQDN)
        host
            Unqualified hostnames
        numeric
            Numeric format

    ether
        Adjust the display of link-level Ethernet (MAC) addresses:

        colon
            Separate address segments with a colon.
        dash
            Separate address segments with a dash.
        default
            Default format, i.e., colon.

    inet
        Adjust the display of inet address subnet masks:

        cidr
            CIDR notation, for example: “10.0.0.0/8”, “203.0.113.224/26”
        default
            Default format, i.e., hex
        dotted
            Dotted quad notation, for example: “255.255.0.0”, “255.255.255.192”
        hex Hexidecimal format, for example: “0xffff0000”, “0xffffffc0”

    inet6
        Adjust the display of inet6 address prefixes (subnet masks):

        cidr
            CIDR notation, for example: “::1/128”, “fe80::1%lo0/64”
        default
            Default format, i.e., numeric
        numeric
            Integer format, for example: “prefixlen 64”

-G groupname
    Exclude members of the specified group from the output.

    Only one -G flag should be specified, as the later one overrides previous ones. The groupname argument may contain shell patterns, but should be quoted in that case.

-g groupname
    Limit the output to the members of the specified group.

    Only one -g flag should be specified, as the later one overrides previous ones. The groupname argument may contain shell patterns, but should be quoted in that case.

    If the -g flag is specified before any other significant flags (e.g., -a or -C), then ifconfig only lists the names of interfaces belonging to the specified group. Any other flags and parameters are ignored in that case.

    Setting groupname to all selects all interfaces.

-k  Print keying information for the interface, if available.

    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.

-L  Display address lifetime for IPv6 addresses as time offset string.

-l  List all available interfaces on the system, with no other additional information.

    If an address_family is specified, only interfaces of that type will be listed. If the address_family is set to ether, then this flag will cause ifconfig to exclude loopback interfaces from the list of Ethernet interfaces. This is a special case, because all other synonyms of the link address family will include loopback interfaces in the list.

    Use of this flag is mutually exclusive with all other flags and parameters, except for -d, -g, and -u.

-m  Display the capability list, the maximum amount of data that TCP segmentation offloading is allowed to aggregate, and all the supported media for an interface.

-n  Disable the automatic loading of network interface drivers.

    By default, if the network interface driver is not present in the kernel, then ifconfig will attempt to load it.

-u  Display only the interfaces that are up.

-v  Get more verbose status for an interface.

interface
    Specify the name of the interface to show or configure. This parameter is usually a string of the form “name unit”, for example, “em0”. If the interface has been renamed, then this form no longer holds; for example, an interface can be renamed to be “vpn-corp”.

address_family
    Specify the address family that 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:

    ether
        Synonymous with link (with some exceptions, see the -l option).
    inet
        Default, if available.
    inet6
    link
        Default if inet is not available.
    lladdr
        Synonymous with link.

address
    For the inet family, the address is either a host name present in the host name data base (see hosts(5)), or an IPv4 address expressed in the Internet standard “dot notation” format.

    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, for example, set a new MAC address on an Ethernet interface, though the mechanism used is not Ethernet-specific.

    If the interface is already up when the link-level address is modified, 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.

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

PARAMETERS

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.

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 Internet Protocol addresses and IEEE 802 48-bit MAC addresses (Ethernet addresses).

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

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.

compress
    Another name for the link0 parameter.

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 the creation of an arbitrary device is successful, the new device name is printed, unless the interface is renamed or destroyed in the same ifconfig invocation.

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

-debug
    Disable driver dependent debugging code.

delete
    Another name for the -alias parameter.

descr[iption] value
    Specify a description for the interface. This can be used to label interfaces in situations where they may otherwise be difficult to distinguish.

-descr[iption]
    Clear the interface description.

destroy
    Destroy the specified network pseudo-device.

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 the specified group. The name of the group may not be longer than 15 characters and must not end in a digit. An interface can be in multiple groups.

    Cloned interfaces are members of their interface family group by default. For example, a tunnel interface such as tun0 is a member of the TUN interface family group, tun.

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

link0, link1, link2
    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.

-link0, -link1, -link2
    Disable special processing at the link level with the specified interface.

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.

metric n
    Set the routing metric of the interface to n; the default is 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.

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.

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.

mtu n
    Set the maximum transmission unit of the interface to n; the 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.

name name
    Set the interface name to name.

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.

noicmp
    Another name for the link1 parameter.

normal
    Another name for the -link0 parameter.

plumb
    Another name for the create parameter. Included for Solaris compatibility.

pollcpu cpu
    (deprecated) Use the polling or npolling parameters below instead.

polling, npolling
    Turn on polling(4) feature and disable interrupts on the interface, if the driver supports this mode.

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

promisc
    Put interface into permanently promiscuous mode.

-promisc
    Disable permanently promiscuous mode.

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

rss If the driver supports Receive Side Scaling (RSS), enable RSS on the interface.

-rss
    If the driver supports Receive Side Scaling (RSS), disable RSS on the interface.

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.

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.

tso If the driver supports TCP segmentation offloading (TSO), enable TSO on the interface.

-tso
    If the driver supports TCP segmentation offloading (TSO), disable TSO on the interface.

tsolen n
    Set the maximum amount of data that TCP segmentation offloading (TSO) is allowed to aggregate to n, the default value is interface specific. This setting only takes effect on interfaces that support TSO.

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

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.

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

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

  IPv6 Parameters
The following parameters are specific to IPv6 addresses. Note that the address_family argument must be specified as inet6 for them.

anycast
    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.

autoconf
    Enable IPv6 auto-configuration.

-autoconf
    Disable IPv6 auto-configuration.

deprecated
    Set the IPv6 deprecated address bit.

-deprecated
    Clear the IPv6 deprecated address bit.

eui64
    Automatically configure the interface identifier (i.e., lowermost 64 bits of an IPv6 address) using the EUI-64 (Extended Unique Identifier) format.

pltime n
    Set the preferred lifetime for the address.

prefixlen len
    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 length can also be specified using the slash notation after the address. See the address option above for more information.

tentative
    Set the IPv6 tentative address bit.

-tentative
    Clear the IPv6 tentative address bit.

vltime n
    Set the valid lifetime for the address.

  IEEE 802.11 Wireless Interface Cloning Parameters
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 be 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 (AP).

  IEEE 802.11 Wireless Cloned Interface Parameters
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 transmission is optional. Use -ampdu to disable all use of AMPDU with 802.11n. For testing and/or to work around interoperability problems one can use ampdutx and ampdurx to control use of 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 microseconds). 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 adapter 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 ‘/’; for example, “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   Same as n
    n   802.11n, aka HT
    s   Atheros Static Turbo mode
    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
    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 current 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 signaling 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 compatibility mechanisms are flagged in list sta operation. To disable compatibility support, use -htcompat.

htprotmode technique
    For interfaces operating in 802.11n, use the specified technique for protecting HT frames in a mixed legacy/HT 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.

    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.

    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 adapter 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.

lscan
    A variant of scan (see below) that displays long SSIDs.

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 choose 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.

powersavemode mode
    Set powersave mode. The set of valid modes is off (same as -powersave), on (same as powersave), and cam (same as powersave).

powersavesleep sleep
    Set the desired max powersave sleep time in TU's (1024 microseconds). 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 choose 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 adapter 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 on the local network and the capabilities of the adapter. 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 adapter 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.

  WLAN ACL Parameters
The following parameters support an optional access control list (ACL) 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).

  WLAN Mesh Mode Parameters
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 a path reply even if it already has a path to this root mesh station,
    RANN
        Send broadcast root announcement (RANN) frames. Nodes on the mesh without a path to this root mesh station with try to discover a path to us.

    By default hwmprootmode is set to DISABLED.

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

  WLAN Compatibility Parameters
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.

  Bridge Interface Parameters
The following parameters are specific to bridge(4) 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 100 entries.

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

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 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.

maxage seconds
    Set the time that a Spanning Tree protocol configuration is valid. The default is 20 seconds. The minimum is 1 second and the maximum is 255 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 1 second and the maximum is 255 seconds.

hellotime seconds
    Set the time between broadcasting of Spanning Tree protocol configuration messages. The default is 2 seconds. The minimum is 1 second and the maximum is 255 seconds.

priority value
    Set the bridge priority for Spanning Tree. The default is 32768. The minimum is 0 and the maximum is 65536.

ifpriority interface value
    Set the Spanning Tree priority of interface to value. The default is 128. The minimum is 0 and the maximum is 255.

    The priority is used to select which interface out of all forwarding and bonded interfaces with the same MAC to output a packet on. The interface with the highest priority will be selected. When multiple interfaces are valid and share the same (highest) priority, the link2 flag on the bridge interface determines determines operation. If not set, packets will only be output on one interface. If set, packets will be round-robined on all valid interfaces sharing the same priority by counting ifbondweight packets on each interface, then moving to the next. Note that interfaces in the “blocking” or any other less-than-good state does not participate in the priority selection. If the priorities are the same on a non-bonded member, the designated member will be used.

ifpathcost interface value
    Set the Spanning Tree path cost of interface to value. The default is 55. The minimum is 0 and the maximum is 65535.

    The path cost is added to both incoming and outgoing packets on the member, lower values will make the member more valuable.

ifbondweight interface value
    Set the number of packets to output on a bonded member before round-robining to the next member. The default is 1. Larger values or different values for each member can be used if bursting would be beneficial or if the outgoing bandwidth on each of the members is asymmetric. For example, one specify a value of 6 on tap0 and 4 on tap1 for a 6:4 ratio. Remember that this also controls packet bursting.

link0
    This option enables transparent bridging mode. The bridge will make every effort to retain the Ethernet header when forwarding packets between interfaces, making the bridging function work more like a hardware bridge device.

link1
    This option enables keepalive transmission and automatically places a member into a special blocked mode if no keepalive reception occurs. If either sides of the link uses this option then both sides must use this option. This option is implemented by sending CFG updates on the hello interval to the remote. The link is considered lost after 10 intervals (typically 20 seconds).

link2
    This option enables channel bonding (see also ifbondweight and ifpriority parameters). All member interfaces with the same MAC address are considered to be in a bonding group. If multiple interfaces in the bonding group share the highest priority via ifpriority, packets will be round-robined between them. When something like tap(4) is used, you can manually control or copy the MAC to create bonding groups. When interface bonding is enabled, normally blocked interfaces belonging to the same bonding group as an active forwarding interface will be changed to the bonding state. Both sides of link the member represents must operate in bonding mode for this to work, otherwise the remote end may decide to throw away half your packets.

proxy
    By default, most interfaces set IFF_ANNOUNCE, aka "proxy". This can be disabled on an interface via the -proxy directive. When set, routes associated with this interface respond to neighbor inquiries when ipv6 forwarding is enabled. Along with other conditions. If forwarding is not enabled, this flag does nothing. The flag may also be used for ipv4 in the future.

  Generic IP Tunnel Parameters
The following parameters are specific to gif(4) IP tunnel interfaces:

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.

  VLAN Parameters
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.

  CARP Parameters
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.

  WireGuard Parameters
The following parameters are available to wg(4) interfaces:

wgkey privatekey
    Set the private key of the interface. The privatekey is 32 bytes in base64 encoding. It can be generated as follows:

        $ openssl rand -base64 32

    The corresponding public key will then be displayed in the interface status for distribution to peers. By default, the status output will exclude the private key, unless the -k flag is specified.

wgpeer publickey
    Add or specify a peer by its publickey, which is also 32 bytes in base64 encoding. Repeat this parameter to specify multiple peers in a single command.

-wgpeer publickey
    Remove the peer with the given publickey.

-wgpeerall
    Remove all peers from the interface.

wgport port
    Set the interface's UDP port for exchanging traffic with its peers. The interface will bind to INADDR_ANY and IN6ADDR_ANY_INIT. By default, the interface will choose a port automatically.

Peer configuration parameters, which apply to the wgpeer parameter immediately preceding them, are as follows:

wgdescr[iption] value
    Specify a description for the peer. This can be used to label peers in situations where they may otherwise be difficult to distinguish.

-wgdescr[iption]
    Clear the peer description.

wgaip address/prefix
    Set the peer's IPv4 or IPv6 address range (in CIDR notation) allowed for its tunneled traffic. Repeat this parameter to set multiple ranges. By default, no address is allowed.

wgendpoint address port
    Address traffic to the peer's IPv4 or IPv6 address and UDP port. The interface will track the peer and update wgendpoint to the source of its last authenticated packet. By default, the endpoint is unknown and so the peer cannot be addressed until it initiates communication. This implies that at least one peer in each pair must specify wgendpoint.

wgpka interval
    Set the interval of persistent keepalive packets in seconds. They can be used to maintain connectivity to a peer otherwise blocked to unsolicited traffic by an intermediate firewall or NAT device. For this, an interval of 25 seconds should suffice. By default, the persistent keepalive is disabled.

-wgpka
    Disable the persistent keepalive for this peer.

wgpsk presharedkey
    Set a unique key pre-shared with the peer. This strengthens the Diffie-Hellman exchange should in future an attack on it become feasible. The presharedkey is also 32 bytes in base64 encoding. It is optional but recommended; it can be generated in the same way as the wgkey private key.

-wgpsk
    Remove the pre-shared key for this peer.

ENVIRONMENT
The following environment variables affect the execution of ifconfig:

IFCONFIG_FORMAT
    This variable can contain a specification of the output format. See the description of the -f option for more details.

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), ifmedia(4), netintro(4), polling(4), vlan(4), wg(4), rc(8), routed(8), sysctl(8)

HISTORY
The ifconfig utility appeared in 4.2BSD.

BUGS
Basic IPv6 node operation requires a link-local address on each interface configured for IPv6. Normally, such an address is automatically configured by the kernel on each interface added to the system; this behavior 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.