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diff --git a/freebsd-userspace/commands/sbin/ifconfig/ifconfig.8 b/freebsd-userspace/commands/sbin/ifconfig/ifconfig.8 new file mode 100644 index 00000000..eaab8fa4 --- /dev/null +++ b/freebsd-userspace/commands/sbin/ifconfig/ifconfig.8 @@ -0,0 +1,2555 @@ +.\" Copyright (c) 1983, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" From: @(#)ifconfig.8 8.3 (Berkeley) 1/5/94 +.\" $FreeBSD$ +.\" +.Dd May 14, 2010 +.Dt IFCONFIG 8 +.Os +.Sh NAME +.Nm ifconfig +.Nd configure network interface parameters +.Sh SYNOPSIS +.Nm +.Op Fl L +.Op Fl k +.Op Fl m +.Op Fl n +.Ar interface +.Op Cm create +.Op Ar address_family +.Oo +.Ar address +.Op Ar dest_address +.Oc +.Op Ar parameters +.Nm +.Ar interface +.Cm destroy +.Nm +.Fl a +.Op Fl L +.Op Fl d +.Op Fl m +.Op Fl u +.Op Fl v +.Op Ar address_family +.Nm +.Fl l +.Op Fl d +.Op Fl u +.Op Ar address_family +.Nm +.Op Fl L +.Op Fl d +.Op Fl k +.Op Fl m +.Op Fl u +.Op Fl v +.Op Fl C +.Nm +.Op Fl g Ar groupname +.Sh DESCRIPTION +The +.Nm +utility is used to assign an address +to a network interface and/or configure +network interface parameters. +The +.Nm +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. +.Pp +The following options are available: +.Bl -tag -width indent +.It Ar address +For the +.Tn DARPA Ns -Internet +family, +the address is either a host name present in the host name data +base, +.Xr hosts 5 , +or a +.Tn DARPA +Internet address expressed in the Internet standard +.Dq dot notation . +.Pp +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 +.Li 192.168.0.1/16 . +.Pp +For the +.Dq inet6 +family, it is also possible to specify the prefix length using the slash +notation, like +.Li ::1/128 . +See the +.Cm prefixlen +parameter below for more information. +.\" For the Xerox Network Systems(tm) family, +.\" addresses are +.\" .Ar net:a.b.c.d.e.f , +.\" where +.\" .Ar net +.\" is the assigned network number (in decimal), +.\" and each of the six bytes of the host number, +.\" .Ar a +.\" through +.\" .Ar f , +.\" are specified in hexadecimal. +.\" The host number may be omitted on IEEE 802 protocol +.\" (Ethernet, FDDI, and Token Ring) interfaces, +.\" which use the hardware physical address, +.\" and on interfaces other than the first. +.\" For the +.\" .Tn ISO +.\" family, addresses are specified as a long hexadecimal string, +.\" as in the Xerox family. +.\" However, two consecutive dots imply a zero +.\" byte, and the dots are optional, if the user wishes to (carefully) +.\" count out long strings of digits in network byte order. +.Pp +The link-level +.Pq Dq link +address +is specified as a series of colon-separated hex digits. +This can be used to +e.g.\& set a new MAC address on an ethernet interface, though the +mechanism used is not ethernet-specific. +If the interface is already +up when this option is used, it will be briefly brought down and +then brought back up again in order to ensure that the receive +filter in the underlying ethernet hardware is properly reprogrammed. +.It Ar address_family +Specify the +address family +which affects interpretation of the remaining parameters. +Since an interface can receive transmissions in differing protocols +with different naming schemes, specifying the address family is recommended. +The address or protocol families currently +supported are +.Dq inet , +.Dq inet6 , +.Dq atalk , +.Dq ipx , +.\" .Dq iso , +and +.Dq link . +.\" and +.\" .Dq ns . +The default is +.Dq inet . +.Dq ether +and +.Dq lladdr +are synonyms for +.Dq link . +.It Ar dest_address +Specify the address of the correspondent on the other end +of a point to point link. +.It Ar interface +This +parameter is a string of the form +.Dq name unit , +for example, +.Dq Li ed0 . +.It Ar groupname +List the interfaces in the given group. +.El +.Pp +The following parameters may be set with +.Nm : +.Bl -tag -width indent +.It Cm add +Another name for the +.Cm alias +parameter. +Introduced for compatibility +with +.Bsx . +.It Cm 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 +.Li 0xffffffff +is most appropriate. +.It Fl 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. +.It Cm 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. +.It Cm arp +Enable the use of the Address Resolution Protocol +.Pq Xr arp 4 +in mapping +between network level addresses and link level addresses (default). +This is currently implemented for mapping between +.Tn DARPA +Internet +addresses and +.Tn IEEE +802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). +.It Fl arp +Disable the use of the Address Resolution Protocol +.Pq Xr arp 4 . +.It Cm staticarp +If the Address Resolution Protocol is enabled, +the host will only reply to requests for its addresses, +and will never send any requests. +.It Fl staticarp +If the Address Resolution Protocol is enabled, +the host will perform normally, +sending out requests and listening for replies. +.It Cm 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. +.It Cm debug +Enable driver dependent debugging code; usually, this turns on +extra console error logging. +.It Fl debug +Disable driver dependent debugging code. +.It Cm promisc +Put interface into permanently promiscuous mode. +.It Fl promisc +Disable permanently promiscuous mode. +.It Cm delete +Another name for the +.Fl alias +parameter. +.It Cm description Ar value , Cm descr Ar value +Specify a description of the interface. +This can be used to label interfaces in situations where they may +otherwise be difficult to distinguish. +.It Cm -description , Cm -descr +Clear the interface description. +.It Cm down +Mark an interface +.Dq down . +When an interface is marked +.Dq 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. +.It Cm group Ar group-name +Assign the interface to a +.Dq group . +Any interface can be in multiple groups. +.Pp +Cloned interfaces are members of their interface family group by default. +For example, a PPP interface such as +.Em ppp0 +is a member of the PPP interface family group, +.Em ppp . +.\" The interface(s) the default route(s) point to are members of the +.\" .Em egress +.\" interface group. +.It Cm -group Ar group-name +Remove the interface from the given +.Dq group . +.It Cm eui64 +(Inet6 only.) +Fill interface index +(lowermost 64bit of an IPv6 address) +automatically. +.It Cm 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. +.It Cm maclabel Ar label +If Mandatory Access Control support is enabled in the kernel, +set the MAC label to +.Ar label . +.\" (see +.\" .Xr maclabel 7 ) . +.It Cm media Ar type +If the driver supports the media selection system, set the media type +of the interface to +.Ar 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 +.Tn AUI +or twisted pair connectors. +Setting the media type to +.Cm 10base5/AUI +would change the currently active connector to the AUI port. +Setting it to +.Cm 10baseT/UTP +would activate twisted pair. +Refer to the interfaces' driver +specific documentation or man page for a complete list of the +available types. +.It Cm mediaopt Ar opts +If the driver supports the media selection system, set the specified +media options on the interface. +The +.Ar 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. +.It Fl mediaopt Ar opts +If the driver supports the media selection system, disable the +specified media options on the interface. +.It Cm mode Ar mode +If the driver supports the media selection system, set the specified +operating mode on the interface to +.Ar mode . +For IEEE 802.11 wireless interfaces that support multiple operating modes +this directive is used to select between 802.11a +.Pq Cm 11a , +802.11b +.Pq Cm 11b , +and 802.11g +.Pq Cm 11g +operating modes. +.It Cm inst Ar minst , Cm instance Ar minst +Set the media instance to +.Ar minst . +This is useful for devices which have multiple physical layer interfaces +.Pq PHYs . +.It Cm name Ar name +Set the interface name to +.Ar name . +.It Cm 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. +.It Fl 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. +.It Cm tso +If the driver supports +.Xr tcp 4 +segmentation offloading, enable TSO on the interface. +Some drivers may not be able to support TSO for +.Xr ip 4 +and +.Xr ip6 4 +packets, so they may enable only one of them. +.It Fl tso +If the driver supports +.Xr tcp 4 +segmentation offloading, disable TSO on the interface. +It will always disable TSO for +.Xr ip 4 +and +.Xr ip6 4 . +.It Cm lro +If the driver supports +.Xr tcp 4 +large receive offloading, enable LRO on the interface. +.It Fl lro +If the driver supports +.Xr tcp 4 +large receive offloading, disable LRO on the interface. +.It Cm 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. +.Cm wol +is a synonym for enabling all available WOL mechanisms. +To disable WOL use +.Fl wol . +.It Cm vlanmtu , vlanhwtag, vlanhwfilter, vlanhwtso +If the driver offers user-configurable VLAN support, enable +reception of extended frames, tag processing in hardware, +frame filtering in hardware, or TSO on VLAN, +respectively. +Note that this must be issued on a physical interface associated with +.Xr vlan 4 , +not on a +.Xr vlan 4 +interface itself. +.It Fl 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. +.It Cm vnet Ar jail +Move the interface to the +.Xr 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. +.It Fl vnet Ar jail +Reclaim the interface from the +.Xr 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. +.It Cm polling +Turn on +.Xr polling 4 +feature and disable interrupts on the interface, if driver supports +this mode. +.It Fl polling +Turn off +.Xr polling 4 +feature and enable interrupt mode on the interface. +.It Cm 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 +.Nm +invocation. +.It Cm destroy +Destroy the specified network pseudo-device. +.It Cm plumb +Another name for the +.Cm create +parameter. +Included for +.Tn Solaris +compatibility. +.It Cm unplumb +Another name for the +.Cm destroy +parameter. +Included for +.Tn Solaris +compatibility. +.It Cm metric Ar n +Set the routing metric of the interface to +.Ar n , +default 0. +The routing metric is used by the routing protocol +.Pq Xr 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. +.It Cm mtu Ar n +Set the maximum transmission unit of the interface to +.Ar 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. +.It Cm netmask Ar mask +.\" (Inet and ISO.) +(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 +.Ql 0x , +with a dot-notation Internet address, +or with a pseudo-network name listed in the network table +.Xr 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. +.Pp +The netmask can also be specified in CIDR notation after the address. +See the +.Ar address +option above for more information. +.It Cm prefixlen Ar len +(Inet6 only.) +Specify that +.Ar len +bits are reserved for subdividing networks into sub-networks. +The +.Ar 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. +.Pp +The prefix can also be specified using the slash notation after the address. +See the +.Ar address +option above for more information. +.\" see +.\" Xr eon 5 . +.\" .It Cm nsellength Ar n +.\" .Pf ( Tn ISO +.\" only) +.\" This specifies a trailing number of bytes for a received +.\" .Tn NSAP +.\" used for local identification, the remaining leading part of which is +.\" taken to be the +.\" .Tn NET +.\" (Network Entity Title). +.\" The default value is 1, which is conformant to US +.\" .Tn GOSIP . +.\" When an ISO address is set in an ifconfig command, +.\" it is really the +.\" .Tn NSAP +.\" which is being specified. +.\" For example, in +.\" .Tn US GOSIP , +.\" 20 hex digits should be +.\" specified in the +.\" .Tn ISO NSAP +.\" to be assigned to the interface. +.\" There is some evidence that a number different from 1 may be useful +.\" for +.\" .Tn AFI +.\" 37 type addresses. +.It Cm range Ar netrange +Under appletalk, set the interface to respond to a +.Ar netrange +of the form +.Ar startnet Ns - Ns Ar endnet . +Appletalk uses this scheme instead of +netmasks though +.Fx +implements it internally as a set of netmasks. +.It Cm remove +Another name for the +.Fl alias +parameter. +Introduced for compatibility +with +.Bsx . +.It Cm phase +The argument following this specifies the version (phase) of the +Appletalk network attached to the interface. +Values of 1 or 2 are permitted. +.Sm off +.It Cm link Op Cm 0 No - Cm 2 +.Sm on +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. +.Sm off +.It Fl link Op Cm 0 No - Cm 2 +.Sm on +Disable special processing at the link level with the specified interface. +.It Cm monitor +Put the interface in monitor mode. +No packets are transmitted, and received packets are discarded after +.Xr bpf 4 +processing. +.It Fl monitor +Take the interface out of monitor mode. +.It Cm up +Mark an interface +.Dq up . +This may be used to enable an interface after an +.Dq Nm Cm 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. +.El +.Pp +The following parameters are for ICMPv6 Neightbor Discovery Protocol: +.Bl -tag -width indent +.It Cm accept_rtadv +Set a flag to enable accepting ICMPv6 Router Advertisement messages. +.It Cm -accept_rtadv +Clear a flag +.Cm accept_rtadv . +.It Cm defaultif +Set the specified interface as the default route when there is no +default router. +.It Cm -defaultif +Clear a flag +.Cm defaultif . +.It Cm ifdisabled +Set a flag to disable all of IPv6 network communications on the +specified interface. +.It Cm -ifdisabled +Clear a flag +.Cm ifdisabled . +.It Cm nud +Set a flag to enable Neighbor Unreachability Detection. +.It Cm -nud +Clear a flag +.Cm nud . +.It Cm prefer_source +Set a flag to prefer addesses on the interface as candidates of the +source address for outgoing packets. +.It Cm -prefer_source +Clear a flag +.Cm prefer_source . +.El +.Pp +The following parameters are specific to cloning +IEEE 802.11 wireless interfaces with the +.Cm create +request: +.Bl -tag -width indent +.It Cm wlandev Ar device +Use +.Ar device +as the parent for the cloned device. +.It Cm wlanmode Ar mode +Specify the operating mode for this cloned device. +.Ar mode +is one of +.Cm sta , +.Cm ahdemo +(or +.Cm adhoc-demo ), +.Cm ibss , +(or +.Cm adhoc ), +.Cm ap , +(or +.Cm hostap ), +.Cm wds , +.Cm tdma , +.Cm mesh , +and +.Cm monitor . +The operating mode of a cloned interface cannot be changed. +The +.Cm tdma +mode is actually implemented as an +.Cm adhoc-demo +interface with special properties. +.It Cm wlanbssid Ar bssid +The 802.11 mac address to use for the bssid. +This must be specified at create time for a legacy +.Cm wds +device. +.It Cm wlanaddr Ar 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 +.Cm bssid +parameter is specified then the driver will craft a unique address for +the device (if supported). +.It Cm wdslegacy +Mark a +.Cm wds +device as operating in ``legacy mode''. +Legacy +.Cm wds +devices have a fixed peer relationship and do not, for example, roam +if their peer stops communicating. +For completeness a Dynamic WDS (DWDS) interface may marked as +.Fl wdslegacy . +.It Cm 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 +.Fl bssid . +.It Cm beacons +Mark the cloned interface as depending on hardware support to +track received beacons. +To have beacons tracked in software use +.Fl beacons . +For +.Cm hostap +mode +.Fl beacons +can also be used to indicate no beacons should +be transmitted; this can be useful when creating a WDS configuration but +.Cm wds +interfaces can only be created as companions to an access point. +.El +.Pp +The following parameters are specific to IEEE 802.11 wireless interfaces +cloned with a +.Cm create +operation: +.Bl -tag -width indent +.It Cm ampdu +Enable sending and receiving AMPDU frames when using 802.11n (default). +The 802.11n specification states a compliant station must be capable +of receiving AMPDU frames but transmision is optional. +Use +.Fl ampdu +to disable all use of AMPDU with 802.11n. +For testing and/or to work around interoperability problems one can use +.Cm ampdutx +and +.Cm ampdurx +to control use of AMPDU in one direction. +.It Cm ampdudensity Ar 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 +.Ar density +are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds). +A value of +.Cm - +is treated the same as 0. +.It Cm ampdulimit Ar limit +Set the limit on packet size for receiving AMPDU frames when operating +with 802.11n. +Legal values for +.Ar 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. +.It Cm amsdu +Enable sending and receiving AMSDU frames when using 802.11n. +By default AMSDU is received but not transmitted. +Use +.Fl amsdu +to disable all use of AMSDU with 802.11n. +For testing and/or to work around interoperability problems one can use +.Cm amsdutx +and +.Cm amsdurx +to control use of AMSDU in one direction. +.It Cm amsdulimit Ar limit +Set the limit on packet size for sending and receiving AMSDU frames +when operating with 802.11n. +Legal values for +.Ar 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. +.It Cm 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 +.Fl apbridge . +Disabling the internal bridging +is useful when traffic is to be processed with +packet filtering. +.It Cm authmode Ar mode +Set the desired authentication mode in infrastructure mode. +Not all adapters support all modes. +The set of +valid modes is +.Cm none , open , shared +(shared key), +.Cm 8021x +(IEEE 802.1x), +and +.Cm wpa +(IEEE WPA/WPA2/802.11i). +The +.Cm 8021x +and +.Cm 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. +.It Cm 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 +.Fl bgscan . +Background scanning is controlled by the +.Cm bgscanidle +and +.Cm 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. +.It Cm bgscanidle Ar idletime +Set the minimum time a station must be idle (not transmitting or +receiving frames) before a background scan is initiated. +The +.Ar 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. +.It Cm bgscanintvl Ar interval +Set the interval at which background scanning is attempted. +The +.Ar interval +parameter is specified in seconds. +By default a background scan is considered every 300 seconds (5 minutes). +The +.Ar interval +may not be set to less than 15 seconds. +.It Cm bintval Ar interval +Set the interval at which beacon frames are sent when operating in +ad-hoc or ap mode. +The +.Ar interval +parameter is specified in TU's (1024 usecs). +By default beacon frames are transmitted every 100 TU's. +.It Cm bmissthreshold Ar 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 +.Ar 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 +.Cm bmissthreshold +parameter is +.Cm bmiss . +.It Cm bssid Ar 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 +.Cm any , none , +or +.Cm - +for the address. +This option is useful when more than one access point uses the same SSID. +Another name for the +.Cm bssid +parameter is +.Cm ap . +.It Cm 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 +.Fl burst . +.It Cm chanlist Ar 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 +.Dq Li a-b . +Channel numbers must be in the range 1 to 255 and be permissible +according to the operating characteristics of the device. +.It Cm channel Ar 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 +.Li any , +or +.Cm - +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. +.Pp +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: +.Cm a +(802.11a), +.Cm b +(802.11b), +.Cm d +(Atheros Dynamic Turbo mode), +.Cm g +(802.11g), +.Cm h +or +.Cm n +(802.11n aka HT), +.Cm s +(Atheros Static Turbo mode), +and +.Cm t +(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt''). +The full set of channel widths following a '/' are: +.Cm 5 +(5MHz aka quarter-rate channel), +.Cm 10 +(10MHz aka half-rate channel), +.Cm 20 +(20MHz mostly for use in specifying ht20), +and +.Cm 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. +.It Cm country Ar 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 +.Cm regdomain , +.Cm indoor , +.Cm outdoor , +and +.Cm anywhere . +.It Cm dfs +Enable Dynamic Frequency Selection (DFS) as specified in 802.11h. +DFS embodies several facilities including detection of overlapping +radar signals, dynamic transmit power control, and channel selection +according to a least-congested criteria. +DFS support is mandatory for some 5Ghz frequencies in certain +locales (e.g. ETSI). +By default DFS is enabled according to the regulatory definitions +specified in /etc/regdomain.xml and the curent country code, regdomain, +and channel. +Note the underlying device (and driver) must support radar detection +for full DFS support to work. +To be fully compliant with the local regulatory agency frequencies that +require DFS should not be used unless it is fully supported. +Use +.Fl dfs +to disable this functionality for testing. +.It Cm 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 +.Fl dotd . +.It Cm 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 +.Fl doth . +.It Cm deftxkey Ar 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 +.Cm weptxkey +is an alias for this request; it is provided for backwards compatibility. +.It Cm dtimperiod Ar period +Set the +DTIM +period for transmitting buffered multicast data frames when +operating in ap mode. +The +.Ar 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). +.It Cm 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 +.Cm list chan +command to identify the channels where turbo mode may be used. +To disable Dynamic Turbo mode use +.Fl dturbo . +.It Cm 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. +.Pp +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. +.Pp +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. +.It Cm 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 +.Fl ff . +.It Cm fragthreshold Ar length +Set the threshold for which transmitted frames are broken into fragments. +The +.Ar length +argument is the frame size in bytes and must be in the range 256 to 2346. +Setting +.Ar length +to +.Li 2346 , +.Cm any , +or +.Cm - +disables transmit fragmentation. +Not all adapters honor the fragmentation threshold. +.It Cm 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 +.Fl hidessid . +.It Cm 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 +.Fl ht . +To disable use of HT20 (e.g. to force only HT40 use) use +.Fl ht20 . +To disable use of HT40 use +.Fl ht40 . +.Pp +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. +.It Cm htcompat +Enable use of compatibility support for pre-802.11n devices (default). +The 802.11n protocol specification went through several incompatible iterations. +Some vendors implemented 11n support to older specifications that +will not interoperate with a purely 11n-compliant station. +In particular the information elements included in management frames +for old devices are different. +When compatibility support is enabled both standard and compatible data +will be provided. +Stations that associate using the compatiblity mechanisms are flagged +in ``list sta''. +To disable compatiblity support use +.Fl htcompat . +.It Cm htprotmode Ar technique +For interfaces operating in 802.11n, use the specified +.Ar technique +for protecting HT frames in a mixed legacy/HT network. +The set of valid techniques is +.Cm off , +and +.Cm rts +(RTS/CTS, default). +Technique names are case insensitive. +.It Cm 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 +.Fl inact . +.It Cm 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 +.Cm dotd . +See also +.Cm outdoor , +.Cm anywhere , +.Cm country , +and +.Cm regdomain . +.It Cm list active +Display the list of channels available for use taking into account +any restrictions set with the +.Cm chanlist +directive. +See the description of +.Cm list chan +for more information. +.It Cm list caps +Display the adaptor's capabilities, including the operating +modes supported. +.It Cm 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 +.Ql 11g +are also usable in +.Ql 11b +mode. +Channels identified as +.Ql 11a Turbo +may be used only for Atheros' Static Turbo mode +(specified with +. Cm mediaopt turbo ) . +Channels marked with a +.Ql * +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. +.Cm list freq +is another way of requesting this information. +By default a compacted list of channels is displayed; if the +.Fl v +option is specified then all channels are shown. +.It Cm list countries +Display the set of country codes and regulatory domains that can be +used in regulatory configuration. +.It Cm 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: +.Ql + +indicates the address is allowed access, +.Ql - +indicates the address is denied access, +.Ql * +indicates the address is present but the current policy open +(so the ACL is not consulted). +.It Cm list mesh +Displays the mesh routing table, used for forwarding packets on a mesh +network. +.It Cm list regdomain +Display the current regulatory settings including the available channels +and transmit power caps. +.It Cm list roam +Display the parameters that govern roaming operation. +.It Cm list txparam +Display the parameters that govern transmit operation. +.It Cm list txpower +Display the transmit power caps for each channel. +.It Cm 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 +.Cm scan +request or through background scanning. +Depending on the capabilities of the stations the following +flags can be included in the output: +.Bl -tag -width 3n +.It Li A +Authorized. +Indicates that the station is permitted to send/receive data frames. +.It Li E +Extended Rate Phy (ERP). +Indicates that the station is operating in an 802.11g network +using extended transmit rates. +.It Li 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 +.Cm htcompat +is enabled. +.It Li P +Power Save. +Indicates that the station is operating in power save mode. +.It Li 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. +.It Li S +Short Preamble. +Indicates that the station is doing short preamble to optionally +improve throughput performance with 802.11g and 802.11b. +.It Li T +Transitional Security Network (TSN). +Indicates that the station associated using TSN; see also +.Cm tsn +below. +.It Li W +Wi-Fi Protected Setup (WPS). +Indicates that the station associated using WPS. +.El +.Pp +By default interesting information elements captured from the neighboring +stations are displayed at the end of each row. +Possible elements include: +.Cm WME +(station supports WME), +.Cm WPA +(station supports WPA), +.Cm WPS +(station supports WPS), +.Cm RSN +(station supports 802.11i/RSN), +.Cm HTCAP +(station supports 802.11n/HT communication), +.Cm ATH +(station supports Atheros protocol extensions), +.Cm VEN +(station supports unknown vendor-specific extensions). +If the +.Fl v +flag is used all the information elements and their +contents will be shown. +Specifying the +.Fl v +flag also enables display of long SSIDs. +The +.Cm list ap +command is another way of requesting this information. +.It Cm 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 +.Cm scan +request. +Depending on the capabilities of the stations the following +flags can be included in the output: +.Bl -tag -width 3n +.It Li A +Authorized. +Indicates that the station is permitted to send/receive data frames. +.It Li E +Extended Rate Phy (ERP). +Indicates that the station is operating in an 802.11g network +using extended transmit rates. +.It Li 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 +.Cm htcompat +is enabled. +.It Li P +Power Save. +Indicates that the station is operating in power save mode. +.It Li 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. +.It Li S +Short Preamble. +Indicates that the station is doing short preamble to optionally +improve throughput performance with 802.11g and 802.11b. +.It Li T +Transitional Security Network (TSN). +Indicates that the station associated using TSN; see also +.Cm tsn +below. +.It Li W +Wi-Fi Protected Setup (WPS). +Indicates that the station associated using WPS. +.El +.Pp +By default information elements received from associated stations +are displayed in a short form; the +.Fl v +flag causes this information to be displayed symbolically. +.It Cm list wme +Display the current channel parameters to use when operating in WME mode. +If the +.Fl 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 +.Cm wme +directive for information on the various parameters. +.It Cm maxretry Ar 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. +.It Cm mcastrate Ar 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. +.It Cm mgtrate Ar 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. +.It Cm 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 +.Cm dotd . +See also +.Cm anywhere , +.Cm country , +.Cm indoor , +and +.Cm regdomain . +.It Cm 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 +.Fl powersave +to disable powersave operation when operating as a client. +.It Cm powersavesleep Ar sleep +Set the desired max powersave sleep time in TU's (1024 usecs). +By default the max powersave sleep time is 100 TU's. +.It Cm protmode Ar technique +For interfaces operating in 802.11g, use the specified +.Ar technique +for protecting OFDM frames in a mixed 11b/11g network. +The set of valid techniques is +.Cm off , cts +(CTS to self), +and +.Cm rtscts +(RTS/CTS). +Technique names are case insensitive. +Not all devices support +.Cm cts +as a protection technique. +.It Cm 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 +.Fl pureg . +.It Cm 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 +.Fl puren . +.It Cm regdomain Ar 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 +.Cm country , +.Cm indoor , +.Cm outdoor , +and +.Cm anywhere . +.It Cm 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 +.Fl rifs . +.It Cm roam:rate Ar rate +Set the threshold for controlling roaming when operating in a BSS. +The +.Ar 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 +.Cm 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). +.It Cm roam:rssi Ar rssi +Set the threshold for controlling roaming when operating in a BSS. +The +.Ar 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 +.Cm 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. +.It Cm roaming Ar mode +When operating as a station, control how the system will +behave when communication with the current access point +is broken. +The +.Ar mode +argument may be one of +.Cm device +(leave it to the hardware device to decide), +.Cm auto +(handle either in the device or the operating system\[em]as appropriate), +.Cm 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 +.Xr wpa_supplicant 8 +that want to control the selection of an access point. +.It Cm rtsthreshold Ar length +Set the threshold for which +transmitted frames are preceded by transmission of an +RTS +control frame. +The +.Ar length +argument +is the frame size in bytes and must be in the range 1 to 2346. +Setting +.Ar length +to +.Li 2346 , +.Cm any , +or +.Cm - +disables transmission of RTS frames. +Not all adapters support setting the RTS threshold. +.It Cm 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 +.Cm 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 +.Cm list scan +request can be used to show recent scan results without +initiating a new scan. +.It Cm scanvalid Ar 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 +.Ar threshold +parameter is specified in seconds and defaults to 60 seconds. +The minimum setting for +.Ar 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. +.It Cm 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 +.Fl shortgi . +.It Cm 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 +.Fl smps . +.It Cm 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 +.Fl smps . +.It Cm ssid Ar 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 +.Ql 0x . +Additionally, the SSID may be cleared by setting it to +.Ql - . +.It Cm tdmaslot Ar slot +When operating with TDMA, use the specified +.Ar slot +configuration. +The +.Ar 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 +.Cm tdmaslot +is set to 1. +.It Cm tdmaslotcnt Ar cnt +When operating with TDMA, setup a BSS with +.Ar 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 +.Cm tdmaslotcnt +is set to 2. +.It Cm tdmaslotlen Ar len +When operating with TDMA, setup a BSS such that each station has a slot +.Ar 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 +.Cm tdmaslotlen +is set to 10 milliseconds. +.It Cm tdmabintval Ar intval +When operating with TDMA, setup a BSS such that beacons are transmitted every +.Ar 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 +.Cm tdmabintval +causes the timers to be resynchronized more often; this can be help if +significant timer drift is observed. +By default +.Cm tdmabintval +is set to 5. +.It Cm 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 +.Fl tsn . +.It Cm txpower Ar power +Set the power used to transmit frames. +The +.Ar 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. +.It Cm ucastrate Ar 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. +.It Cm wepmode Ar mode +Set the desired WEP mode. +Not all adapters support all modes. +The set of valid modes is +.Cm off , on , +and +.Cm mixed . +The +.Cm mixed +mode explicitly tells the adaptor to allow association with access +points which allow both encrypted and unencrypted traffic. +On these adapters, +.Cm on +means that the access point must only allow encrypted connections. +On other adapters, +.Cm on +is generally another name for +.Cm mixed . +Modes are case insensitive. +.It Cm weptxkey Ar index +Set the WEP key to be used for transmission. +This is the same as setting the default transmission key with +.Cm deftxkey . +.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key +Set the selected WEP key. +If an +.Ar index +is not given, key 1 is set. +A WEP key will be either 5 or 13 +characters (40 or 104 bits) depending of the local network and the +capabilities of the adaptor. +It may be specified either as a plain +string or as a string of hexadecimal digits preceded by +.Ql 0x . +For maximum portability, hex keys are recommended; +the mapping of text keys to WEP encryption is usually driver-specific. +In particular, the +.Tn Windows +drivers do this mapping differently to +.Fx . +A key may be cleared by setting it to +.Ql - . +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. +.Pp +Note that you must set a default transmit key with +.Cm deftxkey +for the system to know which key to use in encrypting outbound traffic. +.It Cm 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 +.Fl wme . +Another name for this parameter is +.Cm wmm . +.Pp +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: +.Pp +.Bl -tag -width ".Cm AC_BK" -compact +.It Cm AC_BE +(or +.Cm BE ) +best effort delivery, +.It Cm AC_BK +(or +.Cm BK ) +background traffic, +.It Cm AC_VI +(or +.Cm VI ) +video traffic, +.It Cm AC_VO +(or +.Cm VO ) +voice traffic. +.El +.Pp +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. +.Bl -tag -width indent +.It Cm ack Ar 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 +.Fl ack . +This parameter is applied only to the local station. +.It Cm acm Ar ac +Enable the Admission Control Mandatory (ACM) mechanism +for transmissions by the local station. +To disable the ACM use +.Fl 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. +.It Cm aifs Ar ac Ar 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. +.It Cm cwmin Ar ac Ar 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. +.It Cm cwmax Ar ac Ar 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. +.It Cm txoplimit Ar ac Ar 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. +.It Cm bss:aifs Ar ac Ar count +Set the AIFS channel access parameter to send to stations in a BSS. +This parameter is meaningful only when operating in ap mode. +.It Cm bss:cwmin Ar ac Ar count +Set the CWmin channel access parameter to send to stations in a BSS. +This parameter is meaningful only when operating in ap mode. +.It Cm bss:cwmax Ar ac Ar count +Set the CWmax channel access parameter to send to stations in a BSS. +This parameter is meaningful only when operating in ap mode. +.It Cm bss:txoplimit Ar ac Ar limit +Set the TxOpLimit channel access parameter to send to stations in a BSS. +This parameter is meaningful only when operating in ap mode. +.El +.It Cm wps +Enable Wireless Privacy Subscriber support. +Note that WPS support requires a WPS-capable supplicant. +To disable this function use +.Fl wps . +.El +.Pp +The following parameters support an optional access control list +feature available with some adapters when operating in ap mode; see +.Xr 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. +.Bl -tag -width indent +.It Cm mac:add Ar 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. +.It Cm mac:allow +Set the ACL policy to permit association only by +stations registered in the database. +.It Cm mac:del Ar address +Delete the specified MAC address from the database. +.It Cm mac:deny +Set the ACL policy to deny association only by +stations registered in the database. +.It Cm mac:kick Ar address +Force the specified station to be deauthenticated. +This typically is done to block a station after updating the +address database. +.It Cm mac:open +Set the ACL policy to allow all stations to associate. +.It Cm mac:flush +Delete all entries in the database. +.It Cm mac:radius +Set the ACL policy to permit association only by +stations approved by a RADIUS server. +Note that this feature requires the +.Xr hostapd 8 +program be configured to do the right thing +as it handles the RADIUS processing +(and marks stations as authorized). +.El +.Pp +The following parameters are related to a wireless interface operating in mesh +mode: +.Bl -tag -width indent +.It Cm meshid Ar 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. +.It Cm meshttl Ar 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 +.Cm meshttl +is 31. +.It Cm meshpeering +Enable or disable peering with neighbor mesh stations. +Stations must peer before any data packets can be exchanged. +By default +.Cm meshpeering +is enabled. +.It Cm meshforward +Enable or disable forwarding packets by a mesh interface. +By default +.Cm meshforward +is enabled. +.It Cm meshmetric Ar protocol +Set the specified +.Ar protocol +as the link metric protocol used on a mesh network. +The default protocol is called +.Ar AIRTIME . +The mesh interface will restart after changing this setting. +.It Cm meshpath Ar protocol +Set the specified +.Ar protocol +as the path selection protocol used on a mesh network. +The only available protocol at the moment is called +.Ar HWMP +(Hybrid Wireless Mesh Protocol). +The mesh interface will restart after changing this setting. +.It Cm hwmprootmode Ar 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: +.Pp +.Bl -tag -width ".Cm PROACTIVE" -compact +.It Cm DISABLED +Disable root mode. +.It Cm 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. +.It Cm PROACTIVE +Send broadcast path requests every two seconds and every node must reply with +with a path reply even if it already has a path to this root mesh station, +.It Cm RANN +Send broadcast root annoucement (RANN) frames. +Nodes on the mesh without a path to this root mesh station with try to +discover a path to us. +.El +By default +.Cm hwmprootmode +is set to +.Ar DISABLED . +.It Cm hwmpmaxhops Ar cnt +Set the maximum number of hops allowed in an HMWP path to +.Ar cnt . +The default setting for +.Cm hwmpmaxhops +is 31. +.El +.Pp +The following parameters are for compatibility with other systems: +.Bl -tag -width indent +.It Cm nwid Ar ssid +Another name for the +.Cm ssid +parameter. +Included for +.Nx +compatibility. +.It Cm stationname Ar 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 +.Cm station +for +.Bsx +compatibility. +.It Cm wep +Another way of saying +.Cm wepmode on . +Included for +.Bsx +compatibility. +.It Fl wep +Another way of saying +.Cm wepmode off . +Included for +.Bsx +compatibility. +.It Cm nwkey key +Another way of saying: +.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . +Included for +.Nx +compatibility. +.It Cm nwkey Xo +.Sm off +.Ar n : k1 , k2 , k3 , k4 +.Sm on +.Xc +Another way of saying +.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . +Included for +.Nx +compatibility. +.It Fl nwkey +Another way of saying +.Cm wepmode off . +Included for +.Nx +compatibility. +.El +.Pp +The following parameters are specific to bridge interfaces: +.Bl -tag -width indent +.It Cm addm Ar interface +Add the interface named by +.Ar 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. +.It Cm deletem Ar interface +Remove the interface named by +.Ar interface +from the bridge. +Promiscuous mode is disabled on the interface when +it is removed from the bridge. +.It Cm maxaddr Ar size +Set the size of the bridge address cache to +.Ar size . +The default is 100 entries. +.It Cm timeout Ar seconds +Set the timeout of address cache entries to +.Ar seconds +seconds. +If +.Ar seconds +is zero, then address cache entries will not be expired. +The default is 240 seconds. +.It Cm addr +Display the addresses that have been learned by the bridge. +.It Cm static Ar interface-name Ar address +Add a static entry into the address cache pointing to +.Ar interface-name . +Static entries are never aged out of the cache or re-placed, even if the +address is seen on a different interface. +.It Cm deladdr Ar address +Delete +.Ar address +from the address cache. +.It Cm flush +Delete all dynamically-learned addresses from the address cache. +.It Cm flushall +Delete all addresses, including static addresses, from the address cache. +.It Cm discover Ar interface +Mark an interface as a +.Dq 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 +.Dq discovering . +This is the default for all interfaces added to a bridge. +.It Cm -discover Ar interface +Clear the +.Dq discovering +attribute on a member interface. +For packets without the +.Dq 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. +.It Cm learn Ar interface +Mark an interface as a +.Dq 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. +.It Cm -learn Ar interface +Clear the +.Dq learning +attribute on a member interface. +.It Cm sticky Ar interface +Mark an interface as a +.Dq 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. +.It Cm -sticky Ar interface +Clear the +.Dq sticky +attribute on a member interface. +.It Cm private Ar interface +Mark an interface as a +.Dq private +interface. +A private interface does not forward any traffic to any other port that is also +a private interface. +.It Cm -private Ar interface +Clear the +.Dq private +attribute on a member interface. +.It Cm span Ar interface +Add the interface named by +.Ar 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. +.It Cm -span Ar interface +Delete the interface named by +.Ar interface +from the list of span ports of the bridge. +.It Cm stp Ar interface +Enable Spanning Tree protocol on +.Ar interface . +The +.Xr 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. +.It Cm -stp Ar interface +Disable Spanning Tree protocol on +.Ar interface . +This is the default for all interfaces added to a bridge. +.It Cm edge Ar interface +Set +.Ar 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. +.It Cm -edge Ar interface +Disable edge status on +.Ar interface . +.It Cm autoedge Ar interface +Allow +.Ar interface +to automatically detect edge status. +This is the default for all interfaces added to a bridge. +.It Cm -autoedge Ar interface +Disable automatic edge status on +.Ar interface . +.It Cm ptp Ar interface +Set the +.Ar 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. +.It Cm -ptp Ar interface +Disable point to point link status on +.Ar 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. +.It Cm autoptp Ar interface +Automatically detect the point to point status on +.Ar interface +by checking the full duplex link status. +This is the default for interfaces added to the bridge. +.It Cm -autoptp Ar interface +Disable automatic point to point link detection on +.Ar interface . +.It Cm maxage Ar 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. +.It Cm fwddelay Ar 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. +.It Cm hellotime Ar 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. +.It Cm priority Ar value +Set the bridge priority for Spanning Tree. +The default is 32768. +The minimum is 0 and the maximum is 61440. +.It Cm proto Ar value +Set the Spanning Tree protocol. +The default is rstp. +The available options are stp and rstp. +.It Cm holdcnt Ar 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. +.It Cm ifpriority Ar interface Ar value +Set the Spanning Tree priority of +.Ar interface +to +.Ar value . +The default is 128. +The minimum is 0 and the maximum is 240. +.It Cm ifpathcost Ar interface Ar value +Set the Spanning Tree path cost of +.Ar interface +to +.Ar 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. +.It Cm ifmaxaddr Ar interface Ar 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. +.El +.Pp +The following parameters are specific to lagg interfaces: +.Bl -tag -width indent +.It Cm laggport Ar interface +Add the interface named by +.Ar interface +as a port of the aggregation interface. +.It Cm -laggport Ar interface +Remove the interface named by +.Ar interface +from the aggregation interface. +.It Cm laggproto Ar proto +Set the aggregation protocol. +The default is failover. +The available options are failover, fec, lacp, loadbalance, roundrobin and +none. +.El +.Pp +The following parameters are specific to IP tunnel interfaces, +.Xr gif 4 : +.Bl -tag -width indent +.It Cm tunnel Ar src_addr dest_addr +Configure the physical source and destination address for IP tunnel +interfaces. +The arguments +.Ar src_addr +and +.Ar dest_addr +are interpreted as the outer source/destination for the encapsulating +IPv4/IPv6 header. +.It Fl tunnel +Unconfigure the physical source and destination address for IP tunnel +interfaces previously configured with +.Cm tunnel . +.It Cm deletetunnel +Another name for the +.Fl tunnel +parameter. +.It Cm accept_rev_ethip_ver +Set a flag to acccept both correct EtherIP packets and ones +with reversed version field. Enabled by default. +This is for backward compatibility with +.Fx 6.1 , +6.2, 6.3, 7.0, and 7.1. +.It Cm -accept_rev_ethip_ver +Clear a flag +.Cm accept_rev_ethip_ver . +.It Cm send_rev_ethip_ver +Set a flag to send EtherIP packets with reversed version +field intentionally. Disabled by default. +This is for backward compatibility with +.Fx 6.1 , +6.2, 6.3, 7.0, and 7.1. +.It Cm -send_rev_ethip_ver +Clear a flag +.Cm send_rev_ethip_ver . +.El +.Pp +The following parameters are specific to GRE tunnel interfaces, +.Xr gre 4 : +.Bl -tag -width indent +.It Cm grekey Ar key +Configure the GRE key to be used for outgoing packets. +Note that +.Xr gre 4 will always accept GRE packets with invalid or absent keys. +This command will result in a four byte MTU reduction on the interface. +.El +.Pp +The following parameters are specific to +.Xr pfsync 4 +interfaces: +.Bl -tag -width indent +.It Cm maxupd Ar n +Set the maximum number of updates for a single state which +can be collapsed into one. +This is an 8-bit number; the default value is 128. +.El +.Pp +The following parameters are specific to +.Xr vlan 4 +interfaces: +.Bl -tag -width indent +.It Cm vlan Ar vlan_tag +Set the VLAN tag value to +.Ar vlan_tag . +This value is a 16-bit number which is used to create an 802.1Q +VLAN header for packets sent from the +.Xr vlan 4 +interface. +Note that +.Cm vlan +and +.Cm vlandev +must both be set at the same time. +.It Cm vlandev Ar iface +Associate the physical interface +.Ar iface +with a +.Xr vlan 4 +interface. +Packets transmitted through the +.Xr vlan 4 +interface will be +diverted to the specified physical interface +.Ar 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 +.Xr vlan 4 +pseudo-interface. +The +.Xr vlan 4 +interface is assigned a +copy of the parent interface's flags and the parent's ethernet address. +The +.Cm vlandev +and +.Cm vlan +must both be set at the same time. +If the +.Xr 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. +.Pp +Note: if the hardware tagging capability +is set on the parent interface, the +.Xr vlan 4 +pseudo +interface's behavior changes: +the +.Xr 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. +.It Fl vlandev Op Ar iface +If the driver is a +.Xr vlan 4 +pseudo device, disassociate the parent interface from it. +This breaks the link between the +.Xr vlan 4 +interface and its parent, +clears its VLAN tag, flags and its link address and shuts the interface down. +The +.Ar iface +argument is useless and hence deprecated. +.El +.Pp +The following parameters are specific to +.Xr carp 4 +interfaces: +.Bl -tag -width indent +.It Cm advbase Ar seconds +Specifies the base of the advertisement interval in seconds. +The acceptable values are 1 to 255. +The default value is 1. +.\" The default value is +.\" .Dv CARP_DFLTINTV . +.It Cm advskew Ar 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. +.It Cm pass Ar phrase +Set the authentication key to +.Ar phrase . +.It Cm vhid Ar n +Set the virtual host ID. +This is a required setting. +Acceptable values are 1 to 255. +.El +.Pp +The +.Nm +utility displays the current configuration for a network interface +when no optional parameters are supplied. +If a protocol family is specified, +.Nm +will report only the details specific to that protocol family. +.Pp +If the +.Fl m +flag is passed before an interface name, +.Nm +will display the capability list and all +of the supported media for the specified interface. +If +.Fl L +flag is supplied, address lifetime is displayed for IPv6 addresses, +as time offset string. +.Pp +Optionally, the +.Fl a +flag may be used instead of an interface name. +This flag instructs +.Nm +to display information about all interfaces in the system. +The +.Fl d +flag limits this to interfaces that are down, and +.Fl u +limits this to interfaces that are up. +When no arguments are given, +.Fl a +is implied. +.Pp +The +.Fl 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 +.Fl d +(only list interfaces that are down) +and +.Fl u +(only list interfaces that are up). +.Pp +The +.Fl v +flag may be used to get more verbose status for an interface. +.Pp +The +.Fl 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. +.Pp +The +.Fl k +flag causes keying information for the interface, if available, to be +printed. +For example, the values of 802.11 WEP keys will be printed, if accessible to +the current user. +This information is not printed by default, as it may be considered +sensitive. +.Pp +If the network interface driver is not present in the kernel then +.Nm +will attempt to load it. +The +.Fl n +flag disables this behavior. +.Pp +Only the super-user may modify the configuration of a network interface. +.Sh NOTES +The media selection system is relatively new and only some drivers support +it (or have need for it). +.Sh EXAMPLES +Assign the IPv4 address +.Li 192.0.2.10 , +with a network mask of +.Li 255.255.255.0 , +to the interface +.Li fxp0 : +.Dl # ifconfig fxp0 inet 192.0.2.10 netmask 255.255.255.0 +.Pp +Add the IPv4 address +.Li 192.0.2.45 , +with the CIDR network prefix +.Li /28 , +to the interface +.Li ed0 , +using +.Cm add +as a synonym for the canonical form of the option +.Cm alias : +.Dl # ifconfig ed0 inet 192.0.2.45/28 add +.Pp +Remove the IPv4 address +.Li 192.0.2.45 +from the interface +.Li ed0 : +.Dl # ifconfig ed0 inet 192.0.2.45 -alias +.Pp +Add the IPv6 address +.Li 2001:DB8:DBDB::123/48 +to the interface +.Li em0 : +.Dl # ifconfig em0 inet6 2001:db8:bdbd::123 prefixlen 48 alias +Note that lower case hexadecimal IPv6 addresses are acceptable. +.Pp +Remove the IPv6 address added in the above example, +using the +.Li / +character as shorthand for the network prefix, +and using +.Cm delete +as a synonym for the canonical form of the option +.Fl alias : +.Dl # ifconfig em0 inet6 2001:db8:bdbd::123/48 delete +.Pp +Configure the interface +.Li xl0 , +to use 100baseTX, full duplex Ethernet media options: +.Dl # ifconfig xl0 media 100baseTX mediaopt full-duplex +.Pp +Label the em0 interface as an uplink: +.Pp +.Dl # ifconfig em0 description \&"Uplink to Gigabit Switch 2\&" +.Pp +Create the software network interface +.Li gif1 : +.Dl # ifconfig gif1 create +.Pp +Destroy the software network interface +.Li gif1 : +.Dl # ifconfig gif1 destroy +.Sh 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. +.Sh SEE ALSO +.Xr netstat 1 , +.Xr carp 4 , +.Xr gif 4 , +.Xr netintro 4 , +.Xr pfsync 4 , +.Xr polling 4 , +.Xr vlan 4 , +.\" .Xr eon 5 , +.Xr rc 8 , +.Xr routed 8 , +.Xr jail 8 , +.Xr sysctl 8 +.Sh HISTORY +The +.Nm +utility appeared in +.Bx 4.2 . +.Sh BUGS +Basic IPv6 node operation requires a link-local address on each +interface configured for IPv6. +Normally, such an address is automatically configured by the +kernel on each interface added to the system; this behaviour may +be disabled by setting the sysctl MIB variable +.Va net.inet6.ip6.auto_linklocal +to 0. +.Pp +If you delete such an address using +.Nm , +the kernel may act very odd. +Do this at your own risk. |