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:

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, rxcsum6, txcsum6: If the driver supports user-configurable checksum offloading, enable receive (or transmit) checksum offloading on the interface. The feature can be turned on selectively per protocol family. Use rxcsum6, txcsum6 for ip6(4) or rxcsum, txcsum otherwise. 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, -rxcsum6, -txcsum6: If the driver supports user-configurable checksum offloading, disable receive (or transmit) checksum offloading on the interface. The feature can be turned off selectively per protocol family. Use -rxcsum6, -txcsum6 for ip6(4) or -rxcsum, -txcsum otherwise. 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).
tso6, tso4: If the driver supports tcp(4) segmentation offloading for ip6(4) or ip(4) use one of these to selectively enabled it only for one protocol family.
-tso6, -tso4: If the driver supports tcp(4) segmentation offloading for ip6(4) or ip(4) use one of these to selectively disable it only for one protocol family.
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 Neighbor Discovery Protocol. Note that the address family keyword “ inet6” is needed for them:

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

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 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 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).

quiet

Enable the use of quiet IE. Hostap will use this to silence other stations to reduce interference for radar detection when operating on 5GHz frequency and doth support is enabled. Use -quiet to disable this functionality.

quiet_period period

Set the QUIET period to the number of beacon intervals between the start of regularly scheduled quiet intervals defined by Quiet element.

quiet_count count

Set the QUIET count to the number of TBTTs until the beacon interval during which the next quiet interval shall start. A value of 1 indicates the quiet interval will start during the beacon interval starting at the next TBTT. A value 0 is reserved.

quiet_offset offset

Set the QUIET offset to the offset of the start of the quiet interval from the TBTT specified by the Quiet count, expressed in TUs. The value of the offset shall be less than one beacon interval.

quiet_duration dur

Set the QUIET dur to the duration of the Quiet interval, expressed in TUs. The value should be less than beacon interval.

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 compatibility mechanisms are flagged in ``list sta''. To disable compatibility support use -htcompat.

htprotmode technique

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

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:

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 on the local network and the capabilities of the adaptor. It may be specified either as a plain string or as a string of hexadecimal digits preceded by ‘ 0x’. For 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 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.

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.

meshgate

This attribute specifies whether or not the mesh STA activates mesh gate announcements. By default meshgate is disabled.

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:

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:

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:

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

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

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

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

The following parameters are used to configure carp(4) protocol on an interface:

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 and carp(4) passphrases 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

Enable IPv6 functionality of the interface:

# ifconfig em0 inet6 -ifdisabled

Add the IPv6 address 2001:DB8:DBDB::123/48 to the interface em0:

# ifconfig em0 inet6 2001:db8:bdbd::123 prefixlen 48 alias

Note that lower case hexadecimal IPv6 addresses are acceptable.

Remove the IPv6 address added in the above example, using the / 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 a single CARP redundant address on igb0, and then switch it to be master:

# ifconfig igb0 vhid 1 10.0.0.1/24 pass foobar up

# ifconfig igb0 vhid 1 state master

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.

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 or enabled; this behavior may be disabled by setting per-interface flag -auto_linklocal. The default value of this flag is 1 and can be disabled by using the sysctl MIB variable net.inet6.ip6.auto_linklocal.

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

October 21, 2013

FreeBSD

YOS OPENSONAR

NAME

SYNOPSIS

DESCRIPTION

EXAMPLES

DIAGNOSTICS

SEE ALSO

HISTORY

BUGS