1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" From: @(#)ifconfig.8 8.3 (Berkeley) 1/5/94 29.\" $FreeBSD$ 30.\" 31.Dd August 27, 2008 32.Dt IFCONFIG 8 33.Os 34.Sh NAME 35.Nm ifconfig 36.Nd configure network interface parameters 37.Sh SYNOPSIS 38.Nm 39.Op Fl L 40.Op Fl k 41.Op Fl m 42.Op Fl n 43.Ar interface 44.Op Cm create 45.Op Ar address_family 46.Oo 47.Ar address 48.Op Ar dest_address 49.Oc 50.Op Ar parameters 51.Nm 52.Ar interface 53.Cm destroy 54.Nm 55.Fl a 56.Op Fl L 57.Op Fl d 58.Op Fl m 59.Op Fl u 60.Op Fl v 61.Op Ar address_family 62.Nm 63.Fl l 64.Op Fl d 65.Op Fl u 66.Op Ar address_family 67.Nm 68.Op Fl L 69.Op Fl d 70.Op Fl k 71.Op Fl m 72.Op Fl u 73.Op Fl v 74.Op Fl C 75.Nm 76.Op Fl g Ar groupname 77.Sh DESCRIPTION 78The 79.Nm 80utility is used to assign an address 81to a network interface and/or configure 82network interface parameters. 83The 84.Nm 85utility must be used at boot time to define the network address 86of each interface present on a machine; it may also be used at 87a later time to redefine an interface's address 88or other operating parameters. 89.Pp 90The following options are available: 91.Bl -tag -width indent 92.It Ar address 93For the 94.Tn DARPA Ns -Internet 95family, 96the address is either a host name present in the host name data 97base, 98.Xr hosts 5 , 99or a 100.Tn DARPA 101Internet address expressed in the Internet standard 102.Dq dot notation . 103.Pp 104It is also possible to use the CIDR notation (also known as the 105slash notation) to include the netmask. 106That is, one can specify an address like 107.Li 192.168.0.1/16 . 108.Pp 109For 110.Dq inet6 111family, it is also possible to specify the prefix length using the slash 112notation, like 113.Li ::1/128 . 114See the 115.Cm prefixlen 116parameter below for more information. 117.\" For the Xerox Network Systems(tm) family, 118.\" addresses are 119.\" .Ar net:a.b.c.d.e.f , 120.\" where 121.\" .Ar net 122.\" is the assigned network number (in decimal), 123.\" and each of the six bytes of the host number, 124.\" .Ar a 125.\" through 126.\" .Ar f , 127.\" are specified in hexadecimal. 128.\" The host number may be omitted on IEEE 802 protocol 129.\" (Ethernet, FDDI, and Token Ring) interfaces, 130.\" which use the hardware physical address, 131.\" and on interfaces other than the first. 132.\" For the 133.\" .Tn ISO 134.\" family, addresses are specified as a long hexadecimal string, 135.\" as in the Xerox family. 136.\" However, two consecutive dots imply a zero 137.\" byte, and the dots are optional, if the user wishes to (carefully) 138.\" count out long strings of digits in network byte order. 139.Pp 140The link-level 141.Pq Dq link 142address 143is specified as a series of colon-separated hex digits. 144This can be used to 145e.g.\& set a new MAC address on an ethernet interface, though the 146mechanism used is not ethernet-specific. 147If the interface is already 148up when this option is used, it will be briefly brought down and 149then brought back up again in order to ensure that the receive 150filter in the underlying ethernet hardware is properly reprogrammed. 151.It Ar address_family 152Specify the 153address family 154which affects interpretation of the remaining parameters. 155Since an interface can receive transmissions in differing protocols 156with different naming schemes, specifying the address family is recommended. 157The address or protocol families currently 158supported are 159.Dq inet , 160.Dq inet6 , 161.Dq atalk , 162.Dq ipx , 163.\" .Dq iso , 164and 165.Dq link . 166.\" and 167.\" .Dq ns . 168The default is 169.Dq inet . 170.Dq ether 171and 172.Dq lladdr 173are synonyms for 174.Dq link . 175.It Ar dest_address 176Specify the address of the correspondent on the other end 177of a point to point link. 178.It Ar interface 179This 180parameter is a string of the form 181.Dq name unit , 182for example, 183.Dq Li ed0 . 184.It Ar groupname 185List the interfaces in the given group. 186.El 187.Pp 188The following parameters may be set with 189.Nm : 190.Bl -tag -width indent 191.It Cm add 192Another name for the 193.Cm alias 194parameter. 195Introduced for compatibility 196with 197.Bsx . 198.It Cm alias 199Establish an additional network address for this interface. 200This is sometimes useful when changing network numbers, and 201one wishes to accept packets addressed to the old interface. 202If the address is on the same subnet as the first network address 203for this interface, a non-conflicting netmask must be given. 204Usually 205.Li 0xffffffff 206is most appropriate. 207.It Fl alias 208Remove the network address specified. 209This would be used if you incorrectly specified an alias, or it 210was no longer needed. 211If you have incorrectly set an NS address having the side effect 212of specifying the host portion, removing all NS addresses will 213allow you to respecify the host portion. 214.It Cm anycast 215(Inet6 only.) 216Specify that the address configured is an anycast address. 217Based on the current specification, 218only routers may configure anycast addresses. 219Anycast address will not be used as source address of any of outgoing 220IPv6 packets. 221.It Cm arp 222Enable the use of the Address Resolution Protocol 223.Pq Xr arp 4 224in mapping 225between network level addresses and link level addresses (default). 226This is currently implemented for mapping between 227.Tn DARPA 228Internet 229addresses and 230.Tn IEEE 231802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). 232.It Fl arp 233Disable the use of the Address Resolution Protocol 234.Pq Xr arp 4 . 235.It Cm staticarp 236If the Address Resolution Protocol is enabled, 237the host will only reply to requests for its addresses, 238and will never send any requests. 239.It Fl staticarp 240If the Address Resolution Protocol is enabled, 241the host will perform normally, 242sending out requests and listening for replies. 243.It Cm broadcast 244(Inet only.) 245Specify the address to use to represent broadcasts to the 246network. 247The default broadcast address is the address with a host part of all 1's. 248.It Cm debug 249Enable driver dependent debugging code; usually, this turns on 250extra console error logging. 251.It Fl debug 252Disable driver dependent debugging code. 253.It Cm promisc 254Put interface into permanently promiscuous mode. 255.It Fl promisc 256Disable permanently promiscuous mode. 257.It Cm delete 258Another name for the 259.Fl alias 260parameter. 261.It Cm down 262Mark an interface 263.Dq down . 264When an interface is marked 265.Dq down , 266the system will not attempt to 267transmit messages through that interface. 268If possible, the interface will be reset to disable reception as well. 269This action does not automatically disable routes using the interface. 270.It Cm group Ar group-name 271Assign the interface to a 272.Dq group . 273Any interface can be in multiple groups. 274.Pp 275Cloned interfaces are members of their interface family group by default. 276For example, a PPP interface such as 277.Em ppp0 278is a member of the PPP interface family group, 279.Em ppp . 280.\" The interface(s) the default route(s) point to are members of the 281.\" .Em egress 282.\" interface group. 283.It Cm -group Ar group-name 284Remove the interface from the given 285.Dq group . 286.It Cm eui64 287(Inet6 only.) 288Fill interface index 289(lowermost 64bit of an IPv6 address) 290automatically. 291.It Cm ipdst 292This is used to specify an Internet host who is willing to receive 293IP packets encapsulating IPX packets bound for a remote network. 294An apparent point to point link is constructed, and 295the address specified will be taken as the IPX address and network 296of the destination. 297.It Cm maclabel Ar label 298If Mandatory Access Control support is enabled in the kernel, 299set the MAC label to 300.Ar label . 301.\" (see 302.\" .Xr maclabel 7 ) . 303.It Cm media Ar type 304If the driver supports the media selection system, set the media type 305of the interface to 306.Ar type . 307Some interfaces support the mutually exclusive use of one of several 308different physical media connectors. 309For example, a 10Mbit/s Ethernet 310interface might support the use of either 311.Tn AUI 312or twisted pair connectors. 313Setting the media type to 314.Cm 10base5/AUI 315would change the currently active connector to the AUI port. 316Setting it to 317.Cm 10baseT/UTP 318would activate twisted pair. 319Refer to the interfaces' driver 320specific documentation or man page for a complete list of the 321available types. 322.It Cm mediaopt Ar opts 323If the driver supports the media selection system, set the specified 324media options on the interface. 325The 326.Ar opts 327argument 328is a comma delimited list of options to apply to the interface. 329Refer to the interfaces' driver specific man page for a complete 330list of available options. 331.It Fl mediaopt Ar opts 332If the driver supports the media selection system, disable the 333specified media options on the interface. 334.It Cm mode Ar mode 335If the driver supports the media selection system, set the specified 336operating mode on the interface to 337.Ar mode . 338For IEEE 802.11 wireless interfaces that support multiple operating modes 339this directive is used to select between 802.11a 340.Pq Cm 11a , 341802.11b 342.Pq Cm 11b , 343and 802.11g 344.Pq Cm 11g 345operating modes. 346.It Cm inst Ar minst , Cm instance Ar minst 347Set the media instance to 348.Ar minst . 349This is useful for devices which have multiple physical layer interfaces 350.Pq PHYs . 351.It Cm name Ar name 352Set the interface name to 353.Ar name . 354.It Cm rxcsum , txcsum 355If the driver supports user-configurable checksum offloading, 356enable receive (or transmit) checksum offloading on the interface. 357Some drivers may not be able to enable these flags independently 358of each other, so setting one may also set the other. 359The driver will offload as much checksum work as it can reliably 360support, the exact level of offloading varies between drivers. 361.It Fl rxcsum , txcsum 362If the driver supports user-configurable checksum offloading, 363disable receive (or transmit) checksum offloading on the interface. 364These settings may not always be independent of each other. 365.It Cm tso 366If the driver supports 367.Xr tcp 4 368segmentation offloading, enable TSO on the interface. 369Some drivers may not be able to support TSO for 370.Xr ip 4 371and 372.Xr ip6 4 373packets, so they may enable only one of them. 374.It Fl tso 375If the driver supports 376.Xr tcp 4 377segmentation offloading, disable TSO on the interface. 378It will always disable TSO for 379.Xr ip 4 380and 381.Xr ip6 4 . 382.It Cm lro 383If the driver supports 384.Xr tcp 4 385large receive offloading, enable LRO on the interface. 386.It Fl lro 387If the driver supports 388.Xr tcp 4 389large receive offloading, disable LRO on the interface. 390.It Cm wol , wol_ucast , wol_mcast , wol_magic 391Enable Wake On Lan (WOL) support, if available. 392WOL is a facility whereby a machine in a low power state may be woken 393in response to a received packet. 394There are three types of packets that may wake a system: 395ucast (directed solely to the machine's mac address), 396mcast (directed to a broadcast or multicast address), 397or 398magic (unicast or multicast frames with a ``magic contents''). 399Not all devices support WOL, those that do indicate the mechanisms 400they support in their capabilities. 401.Cm wol 402is a synonym for enabling all available WOL mechanisms. 403To disable WOL use 404.Fl wol . 405.It Cm vlanmtu , vlanhwtag, vlanhwfilter 406If the driver offers user-configurable VLAN support, enable 407reception of extended frames, tag processing in hardware, or 408frame filtering in hardware, 409respectively. 410Note that this must be issued on a physical interface associated with 411.Xr vlan 4 , 412not on a 413.Xr vlan 4 414interface itself. 415.It Fl vlanmtu , vlanhwtag, vlanhwfilter 416If the driver offers user-configurable VLAN support, disable 417reception of extended frames, tag processing in hardware, or 418frame filtering in hardware, 419respectively. 420.It Cm polling 421Turn on 422.Xr polling 4 423feature and disable interrupts on the interface, if driver supports 424this mode. 425.It Fl polling 426Turn off 427.Xr polling 4 428feature and enable interrupt mode on the interface. 429.It Cm create 430Create the specified network pseudo-device. 431If the interface is given without a unit number, try to create a new 432device with an arbitrary unit number. 433If creation of an arbitrary device is successful, the new device name is 434printed to standard output unless the interface is renamed or destroyed 435in the same 436.Nm 437invocation. 438.It Cm destroy 439Destroy the specified network pseudo-device. 440.It Cm plumb 441Another name for the 442.Cm create 443parameter. 444Included for 445.Tn Solaris 446compatibility. 447.It Cm unplumb 448Another name for the 449.Cm destroy 450parameter. 451Included for 452.Tn Solaris 453compatibility. 454.It Cm metric Ar n 455Set the routing metric of the interface to 456.Ar n , 457default 0. 458The routing metric is used by the routing protocol 459.Pq Xr routed 8 . 460Higher metrics have the effect of making a route 461less favorable; metrics are counted as additional hops 462to the destination network or host. 463.It Cm mtu Ar n 464Set the maximum transmission unit of the interface to 465.Ar n , 466default is interface specific. 467The MTU is used to limit the size of packets that are transmitted on an 468interface. 469Not all interfaces support setting the MTU, and some interfaces have 470range restrictions. 471.It Cm netmask Ar mask 472.\" (Inet and ISO.) 473(Inet only.) 474Specify how much of the address to reserve for subdividing 475networks into sub-networks. 476The mask includes the network part of the local address 477and the subnet part, which is taken from the host field of the address. 478The mask can be specified as a single hexadecimal number 479with a leading 480.Ql 0x , 481with a dot-notation Internet address, 482or with a pseudo-network name listed in the network table 483.Xr networks 5 . 484The mask contains 1's for the bit positions in the 32-bit address 485which are to be used for the network and subnet parts, 486and 0's for the host part. 487The mask should contain at least the standard network portion, 488and the subnet field should be contiguous with the network 489portion. 490.Pp 491The netmask can also be specified in CIDR notation after the address. 492See the 493.Ar address 494option above for more information. 495.It Cm prefixlen Ar len 496(Inet6 only.) 497Specify that 498.Ar len 499bits are reserved for subdividing networks into sub-networks. 500The 501.Ar len 502must be integer, and for syntactical reason it must be between 0 to 128. 503It is almost always 64 under the current IPv6 assignment rule. 504If the parameter is omitted, 64 is used. 505.Pp 506The prefix can also be specified using the slash notation after the address. 507See the 508.Ar address 509option above for more information. 510.\" see 511.\" Xr eon 5 . 512.\" .It Cm nsellength Ar n 513.\" .Pf ( Tn ISO 514.\" only) 515.\" This specifies a trailing number of bytes for a received 516.\" .Tn NSAP 517.\" used for local identification, the remaining leading part of which is 518.\" taken to be the 519.\" .Tn NET 520.\" (Network Entity Title). 521.\" The default value is 1, which is conformant to US 522.\" .Tn GOSIP . 523.\" When an ISO address is set in an ifconfig command, 524.\" it is really the 525.\" .Tn NSAP 526.\" which is being specified. 527.\" For example, in 528.\" .Tn US GOSIP , 529.\" 20 hex digits should be 530.\" specified in the 531.\" .Tn ISO NSAP 532.\" to be assigned to the interface. 533.\" There is some evidence that a number different from 1 may be useful 534.\" for 535.\" .Tn AFI 536.\" 37 type addresses. 537.It Cm range Ar netrange 538Under appletalk, set the interface to respond to a 539.Ar netrange 540of the form 541.Ar startnet Ns - Ns Ar endnet . 542Appletalk uses this scheme instead of 543netmasks though 544.Fx 545implements it internally as a set of netmasks. 546.It Cm remove 547Another name for the 548.Fl alias 549parameter. 550Introduced for compatibility 551with 552.Bsx . 553.It Cm phase 554The argument following this specifies the version (phase) of the 555Appletalk network attached to the interface. 556Values of 1 or 2 are permitted. 557.Sm off 558.It Cm link Op Cm 0 No - Cm 2 559.Sm on 560Enable special processing of the link level of the interface. 561These three options are interface specific in actual effect, however, 562they are in general used to select special modes of operation. 563An example 564of this is to enable SLIP compression, or to select the connector type 565for some Ethernet cards. 566Refer to the man page for the specific driver 567for more information. 568.Sm off 569.It Fl link Op Cm 0 No - Cm 2 570.Sm on 571Disable special processing at the link level with the specified interface. 572.It Cm monitor 573Put the interface in monitor mode. 574No packets are transmitted, and received packets are discarded after 575.Xr bpf 4 576processing. 577.It Fl monitor 578Take the interface out of monitor mode. 579.It Cm up 580Mark an interface 581.Dq up . 582This may be used to enable an interface after an 583.Dq Nm Cm down . 584It happens automatically when setting the first address on an interface. 585If the interface was reset when previously marked down, 586the hardware will be re-initialized. 587.El 588.Pp 589The following parameters are specific to cloning 590IEEE 802.11 wireless interfaces with the 591.Cm create 592request: 593.Bl -tag -width indent 594.It Cm wlandev Ar device 595Use 596.Ar device 597as the parent for the cloned device. 598.It Cm wlanmode Ar mode 599Specify the operating mode for this cloned device. 600.Ar mode 601is one of 602.Cm sta , 603.Cm ahdemo 604(or 605.Cm adhoc-demo ), 606.Cm ibss , 607(or 608.Cm adhoc ), 609.Cm ap , 610(or 611.Cm hostap ), 612.Cm wds , 613and 614.Cm monitor . 615The operating mode of a cloned interface cannot be changed. 616.It Cm wlanbssid Ar bssid 617The 802.11 mac address to use for the bssid. 618This must be specified at create time for a legacy 619.Cm wds 620device. 621.It Cm wlanaddr Ar address 622The local mac address. 623If this is not specified then a mac address will automatically be assigned 624to the cloned device. 625Typically this address is the same as the address of the parent device 626but if the 627.Cm bssid 628parameter is specified then the driver will craft a unique address for 629the device (if supported). 630.It Cm wdslegacy 631Mark a 632.Cm wds 633device as operating in ``legacy mode''. 634Legacy 635.Cm wds 636devices have a fixed peer relationship and do not, for example, roam 637if their peer stops communicating. 638For completeness a Dynamic WDS (DWDS) interface may marked as 639.Fl wdslegacy . 640.It Cm bssid 641Request a unique local mac address for the cloned device. 642This is only possible if the device supports multiple mac addresses. 643To force use of the parent's mac address use 644.Fl bssid . 645.It Cm beacons 646Mark the cloned interface as depending on hardware support to 647track received beacons. 648To have beacons tracked in software use 649.Fl beacons . 650For 651.Cm hostap 652mode 653.Fl beacons 654can also be used to indicate no beacons should 655be transmitted; this can be useful when creating a WDS configuration but 656.Cm wds 657interfaces can only be created as companions to an access point. 658.El 659.Pp 660The following parameters are specific to IEEE 802.11 wireless interfaces 661cloned with a 662.Cm create 663operation: 664.Bl -tag -width indent 665.It Cm ampdu 666Enable sending and receiving AMPDU frames when using 802.11n (default). 667The 802.11n specification states a compliant station must be capable 668of receiving AMPDU frames but transmision is optional. 669Use 670.Fl ampdu 671to disable all use of AMPDU with 802.11n. 672For testing and/or to work around interoperability problems one can use 673.Cm ampdutx 674and 675.Cm ampdurx 676to control use of AMPDU in one direction. 677.It Cm ampdudensity Ar density 678Set the AMPDU density parameter used when operating with 802.11n. 679This parameter controls the inter-packet gap for AMPDU frames. 680The sending device normally controls this setting but a receiving station 681may request wider gaps. 682Legal values for 683.Ar density 684are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds). 685A value of 686.Cm - 687is treated the same as 0. 688.It Cm ampdulimit Ar limit 689Set the limit on packet size for receiving AMPDU frames when operating 690with 802.11n. 691Legal values for 692.Ar limit 693are 8192, 16384, 32768, and 65536 but one can also specify 694just the unique prefix: 8, 16, 32, 64. 695Note the sender may limit the size of AMPDU frames to be less 696than the maximum specified by the receiving station. 697.It Cm amsdu 698Enable sending and receiving AMSDU frames when using 802.11n. 699By default AMSDU is received but not transmitted. 700Use 701.Fl amsdu 702to disable all use of AMSDU with 802.11n. 703For testing and/or to work around interoperability problems one can use 704.Cm amsdutx 705and 706.Cm amsdurx 707to control use of AMSDU in one direction. 708.It Cm amsdulimit Ar limit 709Set the limit on packet size for sending and receiving AMSDU frames 710when operating with 802.11n. 711Legal values for 712.Ar limit 713are 7935 and 3839 (bytes). 714Note the sender may limit the size of AMSDU frames to be less 715than the maximum specified by the receiving station. 716Note also that devices are not required to support the 7935 limit, 717only 3839 is required by the specification and the larger value 718may require more memory to be dedicated to support functionality 719that is rarely used. 720.It Cm apbridge 721When operating as an access point, pass packets between 722wireless clients directly (default). 723To instead let them pass up through the 724system and be forwarded using some other mechanism, use 725.Fl apbridge . 726Disabling the internal bridging 727is useful when traffic is to be processed with 728packet filtering. 729.It Cm authmode Ar mode 730Set the desired authentication mode in infrastructure mode. 731Not all adapters support all modes. 732The set of 733valid modes is 734.Cm none , open , shared 735(shared key), 736.Cm 8021x 737(IEEE 802.1x), 738and 739.Cm wpa 740(IEEE WPA/WPA2/802.11i). 741The 742.Cm 8021x 743and 744.Cm wpa 745modes are only useful when using an authentication service 746(a supplicant for client operation or an authenticator when 747operating as an access point). 748Modes are case insensitive. 749.It Cm bgscan 750Enable background scanning when operating as a station. 751Background scanning is a technique whereby a station associated to 752an access point will temporarily leave the channel to scan for 753neighboring stations. 754This allows a station to maintain a cache of nearby access points 755so that roaming between access points can be done without 756a lengthy scan operation. 757Background scanning is done only when a station is not busy and 758any outbound traffic will cancel a scan operation. 759Background scanning should never cause packets to be lost though 760there may be some small latency if outbound traffic interrupts a 761scan operation. 762By default background scanning is enabled if the device is capable. 763To disable background scanning, use 764.Fl bgscan . 765Background scanning is controlled by the 766.Cm bgscanidle 767and 768.Cm bgscanintvl 769parameters. 770Background scanning must be enabled for roaming; this is an artifact 771of the current implementation and may not be required in the future. 772.It Cm bgscanidle Ar idletime 773Set the minimum time a station must be idle (not transmitting or 774receiving frames) before a background scan is initiated. 775The 776.Ar idletime 777parameter is specified in milliseconds. 778By default a station must be idle at least 250 milliseconds before 779a background scan is initiated. 780The idle time may not be set to less than 100 milliseconds. 781.It Cm bgscanintvl Ar interval 782Set the interval at which background scanning is attempted. 783The 784.Ar interval 785parameter is specified in seconds. 786By default a background scan is considered every 300 seconds (5 minutes). 787The 788.Ar interval 789may not be set to less than 15 seconds. 790.It Cm bintval Ar interval 791Set the interval at which beacon frames are sent when operating in 792ad-hoc or ap mode. 793The 794.Ar interval 795parameter is specified in TU's (1024 usecs). 796By default beacon frames are transmitted every 100 TU's. 797.It Cm bmissthreshold Ar count 798Set the number of consecutive missed beacons at which the station 799will attempt to roam (i.e., search for a new access point). 800The 801.Ar count 802parameter must be in the range 1 to 255; though the 803upper bound may be reduced according to device capabilities. 804The default threshold is 7 consecutive missed beacons; but 805this may be overridden by the device driver. 806Another name for the 807.Cm bmissthreshold 808parameter is 809.Cm bmiss . 810.It Cm bssid Ar address 811Specify the MAC address of the access point to use when operating 812as a station in a BSS network. 813This overrides any automatic selection done by the system. 814To disable a previously selected access point, supply 815.Cm any , none , 816or 817.Cm - 818for the address. 819This option is useful when more than one access point uses the same SSID. 820Another name for the 821.Cm bssid 822parameter is 823.Cm ap . 824.It Cm burst 825Enable packet bursting. 826Packet bursting is a transmission technique whereby the wireless 827medium is acquired once to send multiple frames and the interframe 828spacing is reduced. 829This technique can significantly increase throughput by reducing 830transmission overhead. 831Packet bursting is supported by the 802.11e QoS specification 832and some devices that do not support QoS may still be capable. 833By default packet bursting is enabled if a device is capable 834of doing it. 835To disable packet bursting, use 836.Fl burst . 837.It Cm chanlist Ar channels 838Set the desired channels to use when scanning for access 839points, neighbors in an IBSS network, or looking for unoccupied 840channels when operating as an access point. 841The set of channels is specified as a comma-separated list with 842each element in the list representing either a single channel number or a range 843of the form 844.Dq Li a-b . 845Channel numbers must be in the range 1 to 255 and be permissible 846according to the operating characteristics of the device. 847.It Cm channel Ar number 848Set a single desired channel. 849Channels range from 1 to 255, but the exact selection available 850depends on the region your adaptor was manufactured for. 851Setting 852the channel to 853.Li any , 854or 855.Cm - 856will clear any desired channel and, if the device is marked up, 857force a scan for a channel to operate on. 858Alternatively the frequency, in megahertz, may be specified 859instead of the channel number. 860.Pp 861When there are several ways to use a channel the channel 862number/frequency may be appended with attributes to clarify. 863For example, if a device is capable of operating on channel 6 864with 802.11n and 802.11g then one can specify that g-only use 865should be used by specifying ``6:g''. 866Similarly the channel width can be specified by appending it 867with ``/''; e.g. ``6/40'' specifies a 40MHz wide channel, 868These attributes can be combined as in: ``6:ht/40''. 869The full set of flags specified following a `:'' are: 870.Cm a 871(802.11a), 872.Cm b 873(802.11b), 874.Cm d 875(Atheros Dynamic Turbo mode), 876.Cm g 877(802.11g), 878.Cm h 879or 880.Cm n 881(802.11n aka HT), 882.Cm s 883(Atheros Static Turbo mode), 884and 885.Cm t 886(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt''). 887The full set of channel widths following a '/' are: 888.Cm 5 889(5MHz aka quarter-rate channel), 890.Cm 10 891(10MHz aka half-rate channel), 892.Cm 20 893(20MHz mostly for use in specifying ht20), 894and 895.Cm 40 896(40MHz mostly for use in specifying ht40), 897In addition, 898a 40MHz HT channel specification may include the location 899of the extension channel by appending ``+'' or ``-'' for above and below, 900respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation 901with the center channel at frequency 2437 and the extension channel above. 902.It Cm country Ar name 903Set the country code to use in calculating the regulatory constraints 904for operation. 905In particular the set of available channels, how the wireless device 906will operation on the channels, and the maximum transmit power that 907can be used on a channel are defined by this setting. 908Country/Region codes are specified as a 2-character abbreviation 909defined by ISO 3166 or using a longer, but possibly ambiguous, spelling; 910e.g. "ES" and "Spain". 911The set of country codes are taken from /etc/regdomain.xml and can also 912be viewed with the ``list countries'' request. 913Note that not all devices support changing the country code from a default 914setting; typically stored in EEPROM. 915See also 916.Cm regdomain , 917.Cm indoor , 918.Cm outdoor , 919and 920.Cm anywhere . 921.It Cm dfs 922Enable Dynamic Frequency Selection (DFS) as specified in 802.11h. 923DFS embodies several facilities including detection of overlapping 924radar signals, dynamic transmit power control, and channel selection 925according to a least-congested criteria. 926DFS support is mandatory for some 5Ghz frequencies in certain 927locales (e.g. ETSI). 928By default DFS is enabled according to the regulatory definitions 929specified in /etc/regdomain.xml and the curent country code, regdomain, 930and channel. 931Note the underlying device (and driver) must support radar detection 932for full DFS support to work. 933To be fully compliant with the local regulatory agency frequencies that 934require DFS should not be used unless it is fully supported. 935Use 936.Fl dfs 937to disable this functionality for testing. 938.It Cm dotd 939Enable support for the 802.11d specification (default). 940When this support is enabled in station mode, beacon frames that advertise 941a country code different than the currently configured country code will 942cause an event to be dispatched to user applications. 943This event can be used by the station to adopt that country code and 944operate according to the associated regulatory constraints. 945When operating as an access point with 802.11d enabled the beacon and 946probe response frames transmitted will advertise the current regulatory 947domain settings. 948To disable 802.11d use 949.Fl dotd . 950.It Cm doth 951Enable 802.11h support including spectrum management. 952When 802.11h is enabled beacon and probe response frames will have 953the SpectrumMgt bit set in the capabilities field and 954country and power constraint information elements will be present. 955802.11h support also includes handling Channel Switch Announcements (CSA) 956which are a mechanism to coordinate channel changes by an access point. 957By default 802.11h is enabled if the device is capable. 958To disable 802.11h use 959.Fl doth . 960.It Cm deftxkey Ar index 961Set the default key to use for transmission. 962Typically this is only set when using WEP encryption. 963Note that you must set a default transmit key 964for the system to know which key to use in encrypting outbound traffic. 965The 966.Cm weptxkey 967is an alias for this request; it is provided for backwards compatibility. 968.It Cm dtimperiod Ar period 969Set the 970DTIM 971period for transmitting buffered multicast data frames when 972operating in ap mode. 973The 974.Ar period 975specifies the number of beacon intervals between DTIM 976and must be in the range 1 to 15. 977By default DTIM is 1 (i.e., DTIM occurs at each beacon). 978.It Cm dturbo 979Enable the use of Atheros Dynamic Turbo mode when communicating with 980another Dynamic Turbo-capable station. 981Dynamic Turbo mode is an Atheros-specific mechanism by which 982stations switch between normal 802.11 operation and a ``boosted'' 983mode in which a 40MHz wide channel is used for communication. 984Stations using Dynamic Turbo mode operate boosted only when the 985channel is free of non-dturbo stations; when a non-dturbo station 986is identified on the channel all stations will automatically drop 987back to normal operation. 988By default, Dynamic Turbo mode is not enabled, even if the device is capable. 989Note that turbo mode (dynamic or static) is only allowed on some 990channels depending on the regulatory constraints; use the 991.Cm list chan 992command to identify the channels where turbo mode may be used. 993To disable Dynamic Turbo mode use 994.Fl dturbo . 995.It Cm dwds 996Enable Dynamic WDS (DWDS) support. 997DWDS is a facility by which 4-address traffic can be carried between 998stations operating in infrastructure mode. 999A station first associates to an access point and authenticates using 1000normal procedures (e.g. WPA). 1001Then 4-address frames are passed to carry traffic for stations 1002operating on either side of the wireless link. 1003DWDS extends the normal WDS mechanism by leveraging existing security 1004protocols and eliminating static binding. 1005.Pp 1006When DWDS is enabled on an access point 4-address frames received from 1007an authorized station will generate a ``DWDS discovery'' event to user 1008applications. 1009This event should be used to create a WDS interface that is bound 1010to the remote station (and usually plumbed into a bridge). 1011Once the WDS interface is up and running 4-address traffic then logically 1012flows through that interface. 1013.Pp 1014When DWDS is enabled on a station, traffic with a destination address 1015different from the peer station are encapsulated in a 4-address frame 1016and transmitted to the peer. 1017All 4-address traffic uses the security information of the stations 1018(e.g. cryptographic keys). 1019A station is associated using 802.11n facilities may transport 10204-address traffic using these same mechanisms; this depends on available 1021resources and capabilities of the device. 1022The DWDS implementation guards against layer 2 routing loops of 1023multicast traffic. 1024.It Cm ff 1025Enable the use of Atheros Fast Frames when communicating with 1026another Fast Frames-capable station. 1027Fast Frames are an encapsulation technique by which two 802.3 1028frames are transmitted in a single 802.11 frame. 1029This can noticeably improve throughput but requires that the 1030receiving station understand how to decapsulate the frame. 1031Fast frame use is negotiated using the Atheros 802.11 vendor-specific 1032protocol extension so enabling use is safe when communicating with 1033non-Atheros devices. 1034By default, use of fast frames is enabled if the device is capable. 1035To explicitly disable fast frames, use 1036.Fl ff . 1037.It Cm fragthreshold Ar length 1038Set the threshold for which transmitted frames are broken into fragments. 1039The 1040.Ar length 1041argument is the frame size in bytes and must be in the range 256 to 2346. 1042Setting 1043.Ar length 1044to 1045.Li 2346 , 1046.Cm any , 1047or 1048.Cm - 1049disables transmit fragmentation. 1050Not all adapters honor the fragmentation threshold. 1051.It Cm hidessid 1052When operating as an access point, do not broadcast the SSID 1053in beacon frames or respond to probe request frames unless 1054they are directed to the ap (i.e., they include the ap's SSID). 1055By default, the SSID is included in beacon frames and 1056undirected probe request frames are answered. 1057To re-enable the broadcast of the SSID etc., use 1058.Fl hidessid . 1059.It Cm ht 1060Enable use of High Throughput (HT) when using 802.11n (default). 1061The 802.11n specification includes mechanisms for operation 1062on 20MHz and 40MHz wide channels using different signalling mechanisms 1063than specified in 802.11b, 802.11g, and 802.11a. 1064Stations negotiate use of these facilities, termed HT20 and HT40, 1065when they associate. 1066To disable all use of 802.11n use 1067.Fl ht . 1068To disable use of HT20 (e.g. to force only HT40 use) use 1069.Fl ht20 . 1070To disable use of HT40 use 1071.Fl ht40 . 1072.Pp 1073HT configuration is used to ``auto promote'' operation 1074when several choices are available. 1075For example, if a station associates to an 11n-capable access point 1076it controls whether the station uses legacy operation, HT20, or HT40. 1077When an 11n-capable device is setup as an access point and 1078Auto Channel Selection is used to locate a channel to operate on, 1079HT configuration controls whether legacy, HT20, or HT40 operation is setup 1080on the selected channel. 1081If a fixed channel is specified for a station then HT configuration can 1082be given as part of the channel specification; e.g. 6:ht/20 to setup 1083HT20 operation on channel 6. 1084.It Cm htcompat 1085Enable use of compatibility support for pre-802.11n devices (default). 1086The 802.11n protocol specification went through several incompatible iterations. 1087Some vendors implemented 11n support to older specifications that 1088will not interoperate with a purely 11n-compliant station. 1089In particular the information elements included in management frames 1090for old devices are different. 1091When compatibility support is enabled both standard and compatible data 1092will be provided. 1093Stations that associate using the compatiblity mechanisms are flagged 1094in ``list sta''. 1095To disable compatiblity support use 1096.Fl htcompat . 1097.It Cm htprotmode Ar technique 1098For interfaces operating in 802.11n, use the specified 1099.Ar technique 1100for protecting HT frames in a mixed legacy/HT network. 1101The set of valid techniques is 1102.Cm off , 1103and 1104.Cm rts 1105(RTS/CTS, default). 1106Technique names are case insensitive. 1107.It Cm inact 1108Enable inactivity processing for stations associated to an 1109access point (default). 1110When operating as an access point the 802.11 layer monitors 1111the activity of each associated station. 1112When a station is inactive for 5 minutes it will send several 1113``probe frames'' to see if the station is still present. 1114If no response is received then the station is deauthenticated. 1115Applications that prefer to handle this work can disable this 1116facility by using 1117.Fl inact . 1118.It Cm indoor 1119Set the location to use in calculating regulatory constraints. 1120The location is also advertised in beacon and probe response frames 1121when 802.11d is enabled with 1122.Cm dotd . 1123See also 1124.Cm outdoor , 1125.Cm anywhere , 1126.Cm country , 1127and 1128.Cm regdomain . 1129.It Cm list active 1130Display the list of channels available for use taking into account 1131any restrictions set with the 1132.Cm chanlist 1133directive. 1134See the description of 1135.Cm list chan 1136for more information. 1137.It Cm list caps 1138Display the adaptor's capabilities, including the operating 1139modes supported. 1140.It Cm list chan 1141Display the list of channels available for use. 1142Channels are shown with their IEEE channel number, equivalent 1143frequency, and usage modes. 1144Channels identified as 1145.Ql 11g 1146are also usable in 1147.Ql 11b 1148mode. 1149Channels identified as 1150.Ql 11a Turbo 1151may be used only for Atheros' Static Turbo mode 1152(specified with 1153. Cm mediaopt turbo ) . 1154Channels marked with a 1155.Ql * 1156have a regulatory constraint that they be passively scanned. 1157This means a station is not permitted to transmit on the channel until 1158it identifies the channel is being used for 802.11 communication; 1159typically by hearing a beacon frame from an access point operating 1160on the channel. 1161.Cm list freq 1162is another way of requesting this information. 1163By default a compacted list of channels is displayed; if the 1164.Fl v 1165option is specified then all channels are shown. 1166.It Cm list countries 1167Display the set of country codes and regulatory domains that can be 1168used in regulatory configuration. 1169.It Cm list mac 1170Display the current MAC Access Control List state. 1171Each address is prefixed with a character that indicates the 1172current policy applied to it: 1173.Ql + 1174indicates the address is allowed access, 1175.Ql - 1176indicates the address is denied access, 1177.Ql * 1178indicates the address is present but the current policy open 1179(so the ACL is not consulted). 1180.It Cm list regdomain 1181Display the current regulatory settings including the available channels 1182and transmit power caps. 1183.It Cm list roam 1184Display the parameters that govern roaming operation. 1185.It Cm list txparam 1186Display the parameters that govern transmit operation. 1187.It Cm list txpower 1188Display the transmit power caps for each channel. 1189.It Cm list scan 1190Display the access points and/or ad-hoc neighbors 1191located in the vicinity. 1192This information may be updated automatically by the adapter 1193with a 1194.Cm scan 1195request or through background scanning. 1196Depending on the capabilities of the stations the following 1197flags can be included in the output: 1198.Bl -tag -width 3n 1199.It Li A 1200Authorized. 1201Indicates that the station is permitted to send/receive data frames. 1202.It Li E 1203Extended Rate Phy (ERP). 1204Indicates that the station is operating in an 802.11g network 1205using extended transmit rates. 1206.It Li H 1207High Throughput (HT). 1208Indicates that the station is using HT transmit rates. 1209If a `+' follows immediately after then the station associated 1210using deprecated mechanisms supported only when 1211.Cm htcompat 1212is enabled. 1213.It Li P 1214Power Save. 1215Indicates that the station is operating in power save mode. 1216.It Li Q 1217Quality of Service (QoS). 1218Indicates that the station is using QoS encapsulation for 1219data frame. 1220QoS encapsulation is enabled only when WME mode is enabled. 1221.It Li T 1222Transitional Security Network (TSN). 1223Indicates that the station associated using TSN; see also 1224.Cm tsn 1225below. 1226.It Li W 1227Wi-Fi Protected Setup (WPS). 1228Indicates that the station associated using WPS. 1229.El 1230.Pp 1231By default interesting information elements captured from the neighboring 1232stations are displayed at the end of each row. 1233Possible elements include: 1234.Cm WME 1235(station supports WME), 1236.Cm WPA 1237(station supports WPA), 1238.Cm WPS 1239(station supports WPS), 1240.Cm RSN 1241(station supports 802.11i/RSN), 1242.Cm HTCAP 1243(station supports 802.11n/HT communication), 1244.Cm ATH 1245(station supoprts Atheros protocol extensions), 1246.Cm VEN 1247(station supports unknown vendor-specific extensions). 1248If the 1249.Fl v 1250flag is used all the information elements and their 1251contents will be shown. 1252Specifying The 1253.Fl v 1254flag also enables display of long SSIDs. 1255.Cm list ap 1256is another way of requesting this information. 1257.It Cm list sta 1258When operating as an access point display the stations that are 1259currently associated. 1260When operating in ad-hoc mode display stations identified as 1261neighbors in the IBSS. 1262When operating in station mode display the access point. 1263Capabilities advertised by the stations are described under 1264the 1265.Cm scan 1266request. 1267Depending on the capabilities of the stations the following 1268flags can be included in the output: 1269.Bl -tag -width 3n 1270.It Li A 1271Authorized. 1272Indicates that the station is permitted to send/receive data frames. 1273.It Li E 1274Extended Rate Phy (ERP). 1275Indicates that the station is operating in an 802.11g network 1276using extended transmit rates. 1277.It Li H 1278High Throughput (HT). 1279Indicates that the station is using HT transmit rates. 1280If a `+' follows immediately after then the station associated 1281using deprecated mechanisms supported only when 1282.Cm htcompat 1283is enabled. 1284.It Li P 1285Power Save. 1286Indicates that the station is operating in power save mode. 1287.It Li Q 1288Quality of Service (QoS). 1289Indicates that the station is using QoS encapsulation for 1290data frame. 1291QoS encapsulation is enabled only when WME mode is enabled. 1292.It Li T 1293Transitional Security Network (TSN). 1294Indicates that the station associated using TSN; see also 1295.Cm tsn 1296below. 1297.It Li W 1298Wi-Fi Protected Setup (WPS). 1299Indicates that the station associated using WPS. 1300.El 1301.Pp 1302By default information elements received from associated stations 1303are displayed in a short form; the 1304.Fl v 1305flag causes this information to be displayed symbolicaly. 1306.It Cm list wme 1307Display the current channel parameters to use when operating in WME mode. 1308If the 1309.Fl v 1310option is specified then both channel and BSS parameters are displayed 1311for each AC (first channel, then BSS). 1312When WME mode is enabled for an adaptor this information will be 1313displayed with the regular status; this command is mostly useful 1314for examining parameters when WME mode is disabled. 1315See the description of the 1316.Cm wme 1317directive for information on the various parameters. 1318.It Cm maxretry Ar count 1319Set the maximum number of tries to use in sending unicast frames. 1320The default setting is 6 but drivers may override this with a value 1321they choose. 1322.It Cm mcastrate Ar rate 1323Set the rate for transmitting multicast/broadcast frames. 1324Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1325This rate should be valid for the current operating conditions; 1326if an invalid rate is specified drivers are free to chose an 1327appropriate rate. 1328.It Cm mgtrate Ar rate 1329Set the rate for transmitting management and/or control frames. 1330Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1331.It Cm outdoor 1332Set the location to use in calculating regulatory constraints. 1333The location is also advertised in beacon and probe response frames 1334when 802.11d is enabled with 1335.Cm dotd . 1336See also 1337.Cm anywhere , 1338.Cm country , 1339.Cm indoor , 1340and 1341.Cm regdomain . 1342.It Cm powersave 1343Enable powersave operation. 1344When operating as a client, the station will conserve power by 1345periodically turning off the radio and listening for 1346messages from the access point telling it there are packets waiting. 1347The station must then retrieve the packets. 1348Not all devices support power save operation as a client. 1349The 802.11 specification requires that all access points support 1350power save but some drivers do not. 1351Use 1352.Fl powersave 1353to disable powersave operation when operating as a client. 1354.It Cm powersavesleep Ar sleep 1355Set the desired max powersave sleep time in TU's (1024 usecs). 1356By default the max powersave sleep time is 100 TU's. 1357.It Cm protmode Ar technique 1358For interfaces operating in 802.11g, use the specified 1359.Ar technique 1360for protecting OFDM frames in a mixed 11b/11g network. 1361The set of valid techniques is 1362.Cm off , cts 1363(CTS to self), 1364and 1365.Cm rtscts 1366(RTS/CTS). 1367Technique names are case insensitive. 1368Not all devices support 1369.Cm cts 1370as a protection technique. 1371.It Cm pureg 1372When operating as an access point in 802.11g mode allow only 137311g-capable stations to associate (11b-only stations are not 1374permitted to associate). 1375To allow both 11g and 11b-only stations to associate, use 1376.Fl pureg . 1377.It Cm puren 1378When operating as an access point in 802.11n mode allow only 1379HT-capable stations to associate (legacy stations are not 1380permitted to associate). 1381To allow both HT and legacy stations to associate, use 1382.Fl puren . 1383.It Cm regdomain Ar sku 1384Set the regulatory domain to use in calculating the regulatory constraints 1385for operation. 1386In particular the set of available channels, how the wireless device 1387will operation on the channels, and the maximum transmit power that 1388can be used on a channel are defined by this setting. 1389Regdomain codes (SKU's) are taken from /etc/regdomain.xml and can also 1390be viewed with the ``list countries'' request. 1391Note that not all devices support changing the regdomain from a default 1392setting; typically stored in EEPROM. 1393See also 1394.Cm country , 1395.Cm indoor , 1396.Cm outdoor , 1397and 1398.Cm anywhere . 1399.It Cm roam:rate Ar rate 1400Set the threshold for controlling roaming when operating in a BSS. 1401The 1402.Ar rate 1403parameter specifies the transmit rate in megabits 1404at which roaming should be considered. 1405If the current transmit rate drops below this setting and background scanning 1406is enabled, then the system will check if a more desirable access point is 1407available and switch over to it. 1408The current scan cache contents are used if they are considered 1409valid according to the 1410.Cm scanvalid 1411parameter; otherwise a background scan operation is triggered before 1412any selection occurs. 1413Each channel type has a separate rate threshold; the default values are: 141412 Mb/s (11a), 2 Mb/s (11b), 2 Mb/s (11g), MCS 1 (11na, 11ng). 1415.It Cm roam:rssi Ar rssi 1416Set the threshold for controlling roaming when operating in a BSS. 1417The 1418.Ar rssi 1419parameter specifies the receive signal strength in dBm units 1420at which roaming should be considered. 1421If the current rssi drops below this setting and background scanning 1422is enabled, then the system will check if a more desirable access point is 1423available and switch over to it. 1424The current scan cache contents are used if they are considered 1425valid according to the 1426.Cm scanvalid 1427parameter; otherwise a background scan operation is triggered before 1428any selection occurs. 1429Each channel type has a separate rssi threshold; the default values are 1430all 7 dBm. 1431.It Cm roaming Ar mode 1432When operating as a station, control how the system will 1433behave when communication with the current access point 1434is broken. 1435The 1436.Ar mode 1437argument may be one of 1438.Cm device 1439(leave it to the hardware device to decide), 1440.Cm auto 1441(handle either in the device or the operating system\[em]as appropriate), 1442.Cm manual 1443(do nothing until explicitly instructed). 1444By default, the device is left to handle this if it is 1445capable; otherwise, the operating system will automatically 1446attempt to reestablish communication. 1447Manual mode is used by applications such as 1448.Xr wpa_supplicant 8 1449that want to control the selection of an access point. 1450.It Cm rtsthreshold Ar length 1451Set the threshold for which 1452transmitted frames are preceded by transmission of an 1453RTS 1454control frame. 1455The 1456.Ar length 1457argument 1458is the frame size in bytes and must be in the range 1 to 2346. 1459Setting 1460.Ar length 1461to 1462.Li 2346 , 1463.Cm any , 1464or 1465.Cm - 1466disables transmission of RTS frames. 1467Not all adapters support setting the RTS threshold. 1468.It Cm scan 1469Initiate a scan of neighboring stations, wait for it to complete, and 1470display all stations found. 1471Only the super-user can initiate a scan. 1472See 1473.Cm list scan 1474for information on the display. 1475By default a background scan is done; otherwise a foreground 1476scan is done and the station may roam to a different access point. 1477The 1478.Cm list scan 1479request can be used to show recent scan results without 1480initiating a new scan. 1481.It Cm scanvalid Ar threshold 1482Set the maximum time the scan cache contents are considered valid; 1483i.e. will be used without first triggering a scan operation to 1484refresh the data. 1485The 1486.Ar threshold 1487parameter is specified in seconds and defaults to 60 seconds. 1488The minimum setting for 1489.Ar threshold 1490is 10 seconds. 1491One should take care setting this threshold; if it is set too low 1492then attempts to roam to another access point may trigger unnecessary 1493background scan operations. 1494.It Cm shortgi 1495Enable use of Short Guard Interval when operating in 802.11n 1496on an HT channel. 1497NB: this currently enables Short GI on both HT40 and HT20 channels. 1498To disable Short GI use 1499.Fl shortgi . 1500.It Cm ssid Ar ssid 1501Set the desired Service Set Identifier (aka network name). 1502The SSID is a string up to 32 characters 1503in length and may be specified as either a normal string or in 1504hexadecimal when preceded by 1505.Ql 0x . 1506Additionally, the SSID may be cleared by setting it to 1507.Ql - . 1508.It Cm tsn 1509When operating as an access point with WPA/802.11i allow legacy 1510stations to associate using static key WEP and open authentication. 1511To disallow legacy station use of WEP, use 1512.Fl tsn . 1513.It Cm txpower Ar power 1514Set the power used to transmit frames. 1515The 1516.Ar power 1517argument is specified in .5 dBm units. 1518Out of range values are truncated. 1519Typically only a few discreet power settings are available and 1520the driver will use the setting closest to the specified value. 1521Not all adapters support changing the transmit power. 1522.It Cm ucastrate Ar rate 1523Set a fixed rate for transmitting unicast frames. 1524Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1525This rate should be valid for the current operating conditions; 1526if an invalid rate is specified drivers are free to chose an 1527appropriate rate. 1528.It Cm wepmode Ar mode 1529Set the desired WEP mode. 1530Not all adapters support all modes. 1531The set of valid modes is 1532.Cm off , on , 1533and 1534.Cm mixed . 1535The 1536.Cm mixed 1537mode explicitly tells the adaptor to allow association with access 1538points which allow both encrypted and unencrypted traffic. 1539On these adapters, 1540.Cm on 1541means that the access point must only allow encrypted connections. 1542On other adapters, 1543.Cm on 1544is generally another name for 1545.Cm mixed . 1546Modes are case insensitive. 1547.It Cm weptxkey Ar index 1548Set the WEP key to be used for transmission. 1549This is the same as setting the default transmission key with 1550.Cm deftxkey . 1551.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 1552Set the selected WEP key. 1553If an 1554.Ar index 1555is not given, key 1 is set. 1556A WEP key will be either 5 or 13 1557characters (40 or 104 bits) depending of the local network and the 1558capabilities of the adaptor. 1559It may be specified either as a plain 1560string or as a string of hexadecimal digits preceded by 1561.Ql 0x . 1562For maximum portability, hex keys are recommended; 1563the mapping of text keys to WEP encryption is usually driver-specific. 1564In particular, the 1565.Tn Windows 1566drivers do this mapping differently to 1567.Fx . 1568A key may be cleared by setting it to 1569.Ql - . 1570If WEP is supported then there are at least four keys. 1571Some adapters support more than four keys. 1572If that is the case, then the first four keys 1573(1-4) will be the standard temporary keys and any others will be adaptor 1574specific keys such as permanent keys stored in NVRAM. 1575.Pp 1576Note that you must set a default transmit key with 1577.Cm deftxkey 1578for the system to know which key to use in encrypting outbound traffic. 1579.It Cm wme 1580Enable Wireless Multimedia Extensions (WME) support, if available, 1581for the specified interface. 1582WME is a subset of the IEEE 802.11e standard to support the 1583efficient communication of realtime and multimedia data. 1584To disable WME support, use 1585.Fl wme . 1586Another name for this parameter is 1587.Cm wmm . 1588.Pp 1589The following parameters are meaningful only when WME support is in use. 1590Parameters are specified per-AC (Access Category) and 1591split into those that are used by a station when acting 1592as an access point and those for client stations in the BSS. 1593The latter are received from the access point and may not be changed 1594(at the station). 1595The following Access Categories are recognized: 1596.Pp 1597.Bl -tag -width ".Cm AC_BK" -compact 1598.It Cm AC_BE 1599(or 1600.Cm BE ) 1601best effort delivery, 1602.It Cm AC_BK 1603(or 1604.Cm BK ) 1605background traffic, 1606.It Cm AC_VI 1607(or 1608.Cm VI ) 1609video traffic, 1610.It Cm AC_VO 1611(or 1612.Cm VO ) 1613voice traffic. 1614.El 1615.Pp 1616AC parameters are case-insensitive. 1617Traffic classification is done in the operating system using the 1618vlan priority associated with data frames or the 1619ToS (Type of Service) indication in IP-encapsulated frames. 1620If neither information is present, traffic is assigned to the 1621Best Effort (BE) category. 1622.Bl -tag -width indent 1623.It Cm ack Ar ac 1624Set the ACK policy for QoS transmissions by the local station; 1625this controls whether or not data frames transmitted by a station 1626require an ACK response from the receiving station. 1627To disable waiting for an ACK use 1628.Fl ack . 1629This parameter is applied only to the local station. 1630.It Cm acm Ar ac 1631Enable the Admission Control Mandatory (ACM) mechanism 1632for transmissions by the local station. 1633To disable the ACM use 1634.Fl acm . 1635On stations in a BSS this parameter is read-only and indicates 1636the setting received from the access point. 1637NB: ACM is not supported right now. 1638.It Cm aifs Ar ac Ar count 1639Set the Arbitration Inter Frame Spacing (AIFS) 1640channel access parameter to use for transmissions 1641by the local station. 1642On stations in a BSS this parameter is read-only and indicates 1643the setting received from the access point. 1644.It Cm cwmin Ar ac Ar count 1645Set the CWmin channel access parameter to use for transmissions 1646by the local station. 1647On stations in a BSS this parameter is read-only and indicates 1648the setting received from the access point. 1649.It Cm cwmax Ar ac Ar count 1650Set the CWmax channel access parameter to use for transmissions 1651by the local station. 1652On stations in a BSS this parameter is read-only and indicates 1653the setting received from the access point. 1654.It Cm txoplimit Ar ac Ar limit 1655Set the Transmission Opportunity Limit channel access parameter 1656to use for transmissions by the local station. 1657This parameter defines an interval of time when a WME station 1658has the right to initiate transmissions onto the wireless medium. 1659On stations in a BSS this parameter is read-only and indicates 1660the setting received from the access point. 1661.It Cm bss:aifs Ar ac Ar count 1662Set the AIFS channel access parameter to send to stations in a BSS. 1663This parameter is meaningful only when operating in ap mode. 1664.It Cm bss:cwmin Ar ac Ar count 1665Set the CWmin channel access parameter to send to stations in a BSS. 1666This parameter is meaningful only when operating in ap mode. 1667.It Cm bss:cwmax Ar ac Ar count 1668Set the CWmax channel access parameter to send to stations in a BSS. 1669This parameter is meaningful only when operating in ap mode. 1670.It Cm bss:txoplimit Ar ac Ar limit 1671Set the TxOpLimit channel access parameter to send to stations in a BSS. 1672This parameter is meaningful only when operating in ap mode. 1673.El 1674.It Cm wps 1675Enable Wireless Privacy Subscriber support. 1676Note that WPS support requires a WPS-capable supplicant. 1677To disable this function use 1678.Fl wps . 1679.El 1680.Pp 1681The following parameters support an optional access control list 1682feature available with some adapters when operating in ap mode; see 1683.Xr wlan_acl 4 . 1684This facility allows an access point to accept/deny association 1685requests based on the MAC address of the station. 1686Note that this feature does not significantly enhance security 1687as MAC address spoofing is easy to do. 1688.Bl -tag -width indent 1689.It Cm mac:add Ar address 1690Add the specified MAC address to the database. 1691Depending on the policy setting association requests from the 1692specified station will be allowed or denied. 1693.It Cm mac:allow 1694Set the ACL policy to permit association only by 1695stations registered in the database. 1696.It Cm mac:del Ar address 1697Delete the specified MAC address from the database. 1698.It Cm mac:deny 1699Set the ACL policy to deny association only by 1700stations registered in the database. 1701.It Cm mac:kick Ar address 1702Force the specified station to be deauthenticated. 1703This typically is done to block a station after updating the 1704address database. 1705.It Cm mac:open 1706Set the ACL policy to allow all stations to associate. 1707.It Cm mac:flush 1708Delete all entries in the database. 1709.It Cm mac:radius 1710Set the ACL policy to permit association only by 1711stations approved by a RADIUS server. 1712Note that this feature requires the 1713.Xr hostapd 8 1714program be configured to do the right thing 1715as it handles the RADIUS processing 1716(and marks stations as authorized). 1717.El 1718.Pp 1719The following parameters are for compatibility with other systems: 1720.Bl -tag -width indent 1721.It Cm nwid Ar ssid 1722Another name for the 1723.Cm ssid 1724parameter. 1725Included for 1726.Nx 1727compatibility. 1728.It Cm stationname Ar name 1729Set the name of this station. 1730The station name is not part of the IEEE 802.11 1731protocol though some interfaces support it. 1732As such it only 1733seems to be meaningful to identical or virtually identical equipment. 1734Setting the station name is identical in syntax to setting the SSID. 1735One can also use 1736.Cm station 1737for 1738.Bsx 1739compatibility. 1740.It Cm wep 1741Another way of saying 1742.Cm wepmode on . 1743Included for 1744.Bsx 1745compatibility. 1746.It Fl wep 1747Another way of saying 1748.Cm wepmode off . 1749Included for 1750.Bsx 1751compatibility. 1752.It Cm nwkey key 1753Another way of saying: 1754.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 1755Included for 1756.Nx 1757compatibility. 1758.It Cm nwkey Xo 1759.Sm off 1760.Ar n : k1 , k2 , k3 , k4 1761.Sm on 1762.Xc 1763Another way of saying 1764.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 1765Included for 1766.Nx 1767compatibility. 1768.It Fl nwkey 1769Another way of saying 1770.Cm wepmode off . 1771Included for 1772.Nx 1773compatibility. 1774.El 1775.Pp 1776The following parameters are specific to bridge interfaces: 1777.Bl -tag -width indent 1778.It Cm addm Ar interface 1779Add the interface named by 1780.Ar interface 1781as a member of the bridge. 1782The interface is put into promiscuous mode 1783so that it can receive every packet sent on the network. 1784.It Cm deletem Ar interface 1785Remove the interface named by 1786.Ar interface 1787from the bridge. 1788Promiscuous mode is disabled on the interface when 1789it is removed from the bridge. 1790.It Cm maxaddr Ar size 1791Set the size of the bridge address cache to 1792.Ar size . 1793The default is 100 entries. 1794.It Cm timeout Ar seconds 1795Set the timeout of address cache entries to 1796.Ar seconds 1797seconds. 1798If 1799.Ar seconds 1800is zero, then address cache entries will not be expired. 1801The default is 240 seconds. 1802.It Cm addr 1803Display the addresses that have been learned by the bridge. 1804.It Cm static Ar interface-name Ar address 1805Add a static entry into the address cache pointing to 1806.Ar interface-name . 1807Static entries are never aged out of the cache or re-placed, even if the 1808address is seen on a different interface. 1809.It Cm deladdr Ar address 1810Delete 1811.Ar address 1812from the address cache. 1813.It Cm flush 1814Delete all dynamically-learned addresses from the address cache. 1815.It Cm flushall 1816Delete all addresses, including static addresses, from the address cache. 1817.It Cm discover Ar interface 1818Mark an interface as a 1819.Dq discovering 1820interface. 1821When the bridge has no address cache entry 1822(either dynamic or static) 1823for the destination address of a packet, 1824the bridge will forward the packet to all 1825member interfaces marked as 1826.Dq discovering . 1827This is the default for all interfaces added to a bridge. 1828.It Cm -discover Ar interface 1829Clear the 1830.Dq discovering 1831attribute on a member interface. 1832For packets without the 1833.Dq discovering 1834attribute, the only packets forwarded on the interface are broadcast 1835or multicast packets and packets for which the destination address 1836is known to be on the interface's segment. 1837.It Cm learn Ar interface 1838Mark an interface as a 1839.Dq learning 1840interface. 1841When a packet arrives on such an interface, the source 1842address of the packet is entered into the address cache as being a 1843destination address on the interface's segment. 1844This is the default for all interfaces added to a bridge. 1845.It Cm -learn Ar interface 1846Clear the 1847.Dq learning 1848attribute on a member interface. 1849.It Cm sticky Ar interface 1850Mark an interface as a 1851.Dq sticky 1852interface. 1853Dynamically learned address entries are treated at static once entered into 1854the cache. 1855Sticky entries are never aged out of the cache or replaced, even if the 1856address is seen on a different interface. 1857.It Cm -sticky Ar interface 1858Clear the 1859.Dq sticky 1860attribute on a member interface. 1861.It Cm private Ar interface 1862Mark an interface as a 1863.Dq private 1864interface. 1865A private interface does not forward any traffic to any other port that is also 1866a private interface. 1867.It Cm -private Ar interface 1868Clear the 1869.Dq private 1870attribute on a member interface. 1871.It Cm span Ar interface 1872Add the interface named by 1873.Ar interface 1874as a span port on the bridge. 1875Span ports transmit a copy of every frame received by the bridge. 1876This is most useful for snooping a bridged network passively on 1877another host connected to one of the span ports of the bridge. 1878.It Cm -span Ar interface 1879Delete the interface named by 1880.Ar interface 1881from the list of span ports of the bridge. 1882.It Cm stp Ar interface 1883Enable Spanning Tree protocol on 1884.Ar interface . 1885The 1886.Xr if_bridge 4 1887driver has support for the IEEE 802.1D Spanning Tree protocol (STP). 1888Spanning Tree is used to detect and remove loops in a network topology. 1889.It Cm -stp Ar interface 1890Disable Spanning Tree protocol on 1891.Ar interface . 1892This is the default for all interfaces added to a bridge. 1893.It Cm edge Ar interface 1894Set 1895.Ar interface 1896as an edge port. 1897An edge port connects directly to end stations cannot create bridging 1898loops in the network, this allows it to transition straight to forwarding. 1899.It Cm -edge Ar interface 1900Disable edge status on 1901.Ar interface . 1902.It Cm autoedge Ar interface 1903Allow 1904.Ar interface 1905to automatically detect edge status. 1906This is the default for all interfaces added to a bridge. 1907.It Cm -autoedge Ar interface 1908Disable automatic edge status on 1909.Ar interface . 1910.It Cm ptp Ar interface 1911Set the 1912.Ar interface 1913as a point to point link. 1914This is required for straight transitions to forwarding and 1915should be enabled on a direct link to another RSTP capable switch. 1916.It Cm -ptp Ar interface 1917Disable point to point link status on 1918.Ar interface . 1919This should be disabled for a half duplex link and for an interface 1920connected to a shared network segment, 1921like a hub or a wireless network. 1922.It Cm autoptp Ar interface 1923Automatically detect the point to point status on 1924.Ar interface 1925by checking the full duplex link status. 1926This is the default for interfaces added to the bridge. 1927.It Cm -autoptp Ar interface 1928Disable automatic point to point link detection on 1929.Ar interface . 1930.It Cm maxage Ar seconds 1931Set the time that a Spanning Tree protocol configuration is valid. 1932The default is 20 seconds. 1933The minimum is 6 seconds and the maximum is 40 seconds. 1934.It Cm fwddelay Ar seconds 1935Set the time that must pass before an interface begins forwarding 1936packets when Spanning Tree is enabled. 1937The default is 15 seconds. 1938The minimum is 4 seconds and the maximum is 30 seconds. 1939.It Cm hellotime Ar seconds 1940Set the time between broadcasting of Spanning Tree protocol 1941configuration messages. 1942The hello time may only be changed when operating in legacy stp mode. 1943The default is 2 seconds. 1944The minimum is 1 second and the maximum is 2 seconds. 1945.It Cm priority Ar value 1946Set the bridge priority for Spanning Tree. 1947The default is 32768. 1948The minimum is 0 and the maximum is 61440. 1949.It Cm proto Ar value 1950Set the Spanning Tree protocol. 1951The default is rstp. 1952The available options are stp and rstp. 1953.It Cm holdcnt Ar value 1954Set the transmit hold count for Spanning Tree. 1955This is the number of packets transmitted before being rate limited. 1956The default is 6. 1957The minimum is 1 and the maximum is 10. 1958.It Cm ifpriority Ar interface Ar value 1959Set the Spanning Tree priority of 1960.Ar interface 1961to 1962.Ar value . 1963The default is 128. 1964The minimum is 0 and the maximum is 240. 1965.It Cm ifpathcost Ar interface Ar value 1966Set the Spanning Tree path cost of 1967.Ar interface 1968to 1969.Ar value . 1970The default is calculated from the link speed. 1971To change a previously selected path cost back to automatic, set the 1972cost to 0. 1973The minimum is 1 and the maximum is 200000000. 1974.It Cm ifmaxaddr Ar interface Ar size 1975Set the maximum number of hosts allowed from an interface, packets with unknown 1976source addresses are dropped until an existing host cache entry expires or is 1977removed. 1978Set to 0 to disable. 1979.El 1980.Pp 1981The following parameters are specific to lagg interfaces: 1982.Bl -tag -width indent 1983.It Cm laggport Ar interface 1984Add the interface named by 1985.Ar interface 1986as a port of the aggregation interface. 1987.It Cm -laggport Ar interface 1988Remove the interface named by 1989.Ar interface 1990from the aggregation interface. 1991.It Cm laggproto Ar proto 1992Set the aggregation protocol. 1993The default is failover. 1994The available options are failover, fec, lacp, loadbalance, roundrobin and 1995none. 1996.El 1997.Pp 1998The following parameters are specific to IP tunnel interfaces, 1999.Xr gif 4 : 2000.Bl -tag -width indent 2001.It Cm tunnel Ar src_addr dest_addr 2002Configure the physical source and destination address for IP tunnel 2003interfaces. 2004The arguments 2005.Ar src_addr 2006and 2007.Ar dest_addr 2008are interpreted as the outer source/destination for the encapsulating 2009IPv4/IPv6 header. 2010.It Fl tunnel 2011Unconfigure the physical source and destination address for IP tunnel 2012interfaces previously configured with 2013.Cm tunnel . 2014.It Cm deletetunnel 2015Another name for the 2016.Fl tunnel 2017parameter. 2018.El 2019.Pp 2020The following parameters are specific to GRE tunnel interfaces, 2021.Xr gre 4 : 2022.Bl -tag -width indent 2023.It Cm grekey Ar key 2024Configure the GRE key to be used for outgoing packets. 2025Note that 2026.Xr gre 4 will always accept GRE packets with invalid or absent keys. 2027This command will result in a four byte MTU reduction on the interface. 2028.El 2029.Pp 2030The following parameters are specific to 2031.Xr pfsync 4 2032interfaces: 2033.Bl -tag -width indent 2034.It Cm maxupd Ar n 2035Set the maximum number of updates for a single state which 2036can be collapsed into one. 2037This is an 8-bit number; the default value is 128. 2038.El 2039.Pp 2040The following parameters are specific to 2041.Xr vlan 4 2042interfaces: 2043.Bl -tag -width indent 2044.It Cm vlan Ar vlan_tag 2045Set the VLAN tag value to 2046.Ar vlan_tag . 2047This value is a 16-bit number which is used to create an 802.1Q 2048VLAN header for packets sent from the 2049.Xr vlan 4 2050interface. 2051Note that 2052.Cm vlan 2053and 2054.Cm vlandev 2055must both be set at the same time. 2056.It Cm vlandev Ar iface 2057Associate the physical interface 2058.Ar iface 2059with a 2060.Xr vlan 4 2061interface. 2062Packets transmitted through the 2063.Xr vlan 4 2064interface will be 2065diverted to the specified physical interface 2066.Ar iface 2067with 802.1Q VLAN encapsulation. 2068Packets with 802.1Q encapsulation received 2069by the parent interface with the correct VLAN tag will be diverted to 2070the associated 2071.Xr vlan 4 2072pseudo-interface. 2073The 2074.Xr vlan 4 2075interface is assigned a 2076copy of the parent interface's flags and the parent's ethernet address. 2077The 2078.Cm vlandev 2079and 2080.Cm vlan 2081must both be set at the same time. 2082If the 2083.Xr vlan 4 2084interface already has 2085a physical interface associated with it, this command will fail. 2086To 2087change the association to another physical interface, the existing 2088association must be cleared first. 2089.Pp 2090Note: if the hardware tagging capability 2091is set on the parent interface, the 2092.Xr vlan 4 2093pseudo 2094interface's behavior changes: 2095the 2096.Xr vlan 4 2097interface recognizes that the 2098parent interface supports insertion and extraction of VLAN tags on its 2099own (usually in firmware) and that it should pass packets to and from 2100the parent unaltered. 2101.It Fl vlandev Op Ar iface 2102If the driver is a 2103.Xr vlan 4 2104pseudo device, disassociate the parent interface from it. 2105This breaks the link between the 2106.Xr vlan 4 2107interface and its parent, 2108clears its VLAN tag, flags and its link address and shuts the interface down. 2109The 2110.Ar iface 2111argument is useless and hence deprecated. 2112.El 2113.Pp 2114The following parameters are specific to 2115.Xr carp 4 2116interfaces: 2117.Bl -tag -width indent 2118.It Cm advbase Ar seconds 2119Specifies the base of the advertisement interval in seconds. 2120The acceptable values are 1 to 255. 2121The default value is 1. 2122.\" The default value is 2123.\" .Dv CARP_DFLTINTV . 2124.It Cm advskew Ar interval 2125Specifies the skew to add to the base advertisement interval to 2126make one host advertise slower than another host. 2127It is specified in 1/256 of seconds. 2128The acceptable values are 1 to 254. 2129The default value is 0. 2130.It Cm pass Ar phrase 2131Set the authentication key to 2132.Ar phrase . 2133.It Cm vhid Ar n 2134Set the virtual host ID. 2135This is a required setting. 2136Acceptable values are 1 to 255. 2137.El 2138.Pp 2139The 2140.Nm 2141utility displays the current configuration for a network interface 2142when no optional parameters are supplied. 2143If a protocol family is specified, 2144.Nm 2145will report only the details specific to that protocol family. 2146.Pp 2147If the 2148.Fl m 2149flag is passed before an interface name, 2150.Nm 2151will display the capability list and all 2152of the supported media for the specified interface. 2153If 2154.Fl L 2155flag is supplied, address lifetime is displayed for IPv6 addresses, 2156as time offset string. 2157.Pp 2158Optionally, the 2159.Fl a 2160flag may be used instead of an interface name. 2161This flag instructs 2162.Nm 2163to display information about all interfaces in the system. 2164The 2165.Fl d 2166flag limits this to interfaces that are down, and 2167.Fl u 2168limits this to interfaces that are up. 2169When no arguments are given, 2170.Fl a 2171is implied. 2172.Pp 2173The 2174.Fl l 2175flag may be used to list all available interfaces on the system, with 2176no other additional information. 2177Use of this flag is mutually exclusive 2178with all other flags and commands, except for 2179.Fl d 2180(only list interfaces that are down) 2181and 2182.Fl u 2183(only list interfaces that are up). 2184.Pp 2185The 2186.Fl v 2187flag may be used to get more verbose status for an interface. 2188.Pp 2189The 2190.Fl C 2191flag may be used to list all of the interface cloners available on 2192the system, with no additional information. 2193Use of this flag is mutually exclusive with all other flags and commands. 2194.Pp 2195The 2196.Fl k 2197flag causes keying information for the interface, if available, to be 2198printed. 2199For example, the values of 802.11 WEP keys will be printed, if accessible to 2200the current user. 2201This information is not printed by default, as it may be considered 2202sensitive. 2203.Pp 2204If the network interface driver is not present in the kernel then 2205.Nm 2206will attempt to load it. 2207The 2208.Fl n 2209flag disables this behavior. 2210.Pp 2211Only the super-user may modify the configuration of a network interface. 2212.Sh NOTES 2213The media selection system is relatively new and only some drivers support 2214it (or have need for it). 2215.Sh EXAMPLES 2216Assign the IPv4 address 2217.Li 192.0.2.10 , 2218with a network mask of 2219.Li 255.255.255.0 , 2220to the interface 2221.Li fxp0 : 2222.Dl # ifconfig fxp0 inet 192.0.2.10 netmask 255.255.255.0 2223.Pp 2224Add the IPv4 address 2225.Li 192.0.2.45 , 2226with the CIDR network prefix 2227.Li /28 , 2228to the interface 2229.Li ed0 , 2230using 2231.Cm add 2232as a synonym for the canonical form of the option 2233.Cm alias : 2234.Dl # ifconfig ed0 inet 192.0.2.45/28 add 2235.Pp 2236Remove the IPv4 address 2237.Li 192.0.2.45 2238from the interface 2239.Li ed0 : 2240.Dl # ifconfig ed0 inet 192.0.2.45 -alias 2241.Pp 2242Add the IPv6 address 2243.Li 2001:DB8:DBDB::123/48 2244to the interface 2245.Li em0 : 2246.Dl # ifconfig em0 inet6 2001:db8:bdbd::123 prefixlen 48 alias 2247Note that lower case hexadecimal IPv6 addresses are acceptable. 2248.Pp 2249Remove the IPv6 address added in the above example, 2250using the 2251.Li / 2252character as shorthand for the network prefix, 2253and using 2254.Cm delete 2255as a synonym for the canonical form of the option 2256.Fl alias : 2257.Dl # ifconfig em0 inet6 2001:db8:bdbd::123/48 delete 2258.Pp 2259Configure the interface 2260.Li xl0 , 2261to use 100baseTX, full duplex Ethernet media options: 2262.Dl # ifconfig xl0 media 100baseTX mediaopt full-duplex 2263.Pp 2264Create the software network interface 2265.Li gif1 : 2266.Dl # ifconfig gif1 create 2267.Pp 2268Destroy the software network interface 2269.Li gif1 : 2270.Dl # ifconfig gif1 destroy 2271.Sh DIAGNOSTICS 2272Messages indicating the specified interface does not exist, the 2273requested address is unknown, or the user is not privileged and 2274tried to alter an interface's configuration. 2275.Sh SEE ALSO 2276.Xr netstat 1 , 2277.Xr carp 4 , 2278.Xr netintro 4 , 2279.Xr pfsync 4 , 2280.Xr polling 4 , 2281.Xr vlan 4 , 2282.\" .Xr eon 5 , 2283.Xr rc 8 , 2284.Xr routed 8 , 2285.Xr sysctl 8 2286.Sh HISTORY 2287The 2288.Nm 2289utility appeared in 2290.Bx 4.2 . 2291.Sh BUGS 2292Basic IPv6 node operation requires a link-local address on each 2293interface configured for IPv6. 2294Normally, such an address is automatically configured by the 2295kernel on each interface added to the system; this behaviour may 2296be disabled by setting the sysctl MIB variable 2297.Va net.inet6.ip6.auto_linklocal 2298to 0. 2299.Pp 2300If you delete such an address using 2301.Nm , 2302the kernel may act very odd. 2303Do this at your own risk. 2304