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: src/sbin/ifconfig/ifconfig.8,v 1.124 2006/10/10 09:44:08 ru Exp $ 30.\" 31.Dd July 17, 2010 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.Ar interface 43.Op Cm create 44.Op Ar address_family 45.Oo 46.Ar address 47.Op Ar dest_address 48.Oc 49.Op Ar parameters 50.Nm 51.Ar interface 52.Cm destroy 53.Nm 54.Fl a 55.Op Fl L 56.Op Fl d 57.Op Fl m 58.Op Fl u 59.Op Fl v 60.Op Ar address_family 61.Nm 62.Fl l 63.Op Fl d 64.Op Fl u 65.Op Ar address_family 66.Nm 67.Op Fl L 68.Op Fl d 69.Op Fl k 70.Op Fl m 71.Op Fl u 72.Op Fl v 73.Op Fl C 74.Sh DESCRIPTION 75The 76.Nm 77utility is used to assign an address 78to a network interface and/or configure 79network interface parameters. 80The 81.Nm 82utility must be used at boot time to define the network address 83of each interface present on a machine; it may also be used at 84a later time to redefine an interface's address 85or other operating parameters. 86.Pp 87The following options are available: 88.Bl -tag -width indent 89.It Ar address 90For the 91.Tn DARPA Ns -Internet 92family, 93the address is either a host name present in the host name data 94base, 95.Xr hosts 5 , 96or a 97.Tn DARPA 98Internet address expressed in the Internet standard 99.Dq dot notation . 100.Pp 101It is also possible to use the CIDR notation (also known as the 102slash notation) to include the netmask. 103That is, one can specify an address like 104.Li 192.168.0.1/16 . 105.Pp 106For 107.Dq inet6 108family, it is also possible to specify the prefix length using the slash 109notation, like 110.Li ::1/128 . 111See the 112.Cm prefixlen 113parameter below for more information. 114.\" For the Xerox Network Systems(tm) family, 115.\" addresses are 116.\" .Ar net:a.b.c.d.e.f , 117.\" where 118.\" .Ar net 119.\" is the assigned network number (in decimal), 120.\" and each of the six bytes of the host number, 121.\" .Ar a 122.\" through 123.\" .Ar f , 124.\" are specified in hexadecimal. 125.\" The host number may be omitted on IEEE 802 protocol 126.\" (Ethernet, FDDI, and Token Ring) interfaces, 127.\" which use the hardware physical address, 128.\" and on interfaces other than the first. 129.\" For the 130.\" .Tn ISO 131.\" family, addresses are specified as a long hexadecimal string, 132.\" as in the Xerox family. 133.\" However, two consecutive dots imply a zero 134.\" byte, and the dots are optional, if the user wishes to (carefully) 135.\" count out long strings of digits in network byte order. 136.Pp 137The link-level 138.Pq Dq link 139address 140is specified as a series of colon-separated hex digits. 141This can be used to 142e.g.\& set a new MAC address on an ethernet interface, though the 143mechanism used is not ethernet-specific. 144If the interface is already 145up when this option is used, it will be briefly brought down and 146then brought back up again in order to ensure that the receive 147filter in the underlying ethernet hardware is properly reprogrammed. 148.It Ar address_family 149Specify the 150address family 151which affects interpretation of the remaining parameters. 152Since an interface can receive transmissions in differing protocols 153with different naming schemes, specifying the address family is recommended. 154The address or protocol families currently 155supported are 156.Dq inet , 157.Dq inet6 , 158.Dq atalk , 159.Dq ipx , 160.\" .Dq iso , 161and 162.Dq link . 163.\" and 164.\" .Dq ns . 165The default is 166.Dq inet . 167.Dq ether 168and 169.Dq lladdr 170are synonyms for 171.Dq link . 172.It Ar dest_address 173Specify the address of the correspondent on the other end 174of a point to point link. 175.It Ar interface 176This 177parameter is a string of the form 178.Dq name unit , 179for example, 180.Dq Li ed0 . 181.El 182.Pp 183The following parameters may be set with 184.Nm : 185.Bl -tag -width indent 186.It Cm add 187Another name for the 188.Cm alias 189parameter. 190Introduced for compatibility 191with 192.Bsx . 193.It Cm alias 194Establish an additional network address for this interface. 195This is sometimes useful when changing network numbers, and 196one wishes to accept packets addressed to the old interface. 197If the address is on the same subnet as the first network address 198for this interface, a non-conflicting netmask must be given. 199Usually 200.Li 0xffffffff 201is most appropriate. 202.It Fl alias 203Remove the network address specified. 204This would be used if you incorrectly specified an alias, or it 205was no longer needed. 206If you have incorrectly set an NS address having the side effect 207of specifying the host portion, removing all NS addresses will 208allow you to respecify the host portion. 209.It Cm anycast 210(Inet6 only.) 211Specify that the address configured is an anycast address. 212Based on the current specification, 213only routers may configure anycast addresses. 214Anycast address will not be used as source address of any of outgoing 215IPv6 packets. 216.It Cm arp 217Enable the use of the Address Resolution Protocol 218.Pq Xr arp 4 219in mapping 220between network level addresses and link level addresses (default). 221This is currently implemented for mapping between 222.Tn DARPA 223Internet 224addresses and 225.Tn IEEE 226802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). 227.It Fl arp 228Disable the use of the Address Resolution Protocol 229.Pq Xr arp 4 . 230.It Cm staticarp 231If the Address Resolution Protocol is enabled, 232the host will only reply to requests for its addresses, 233and will never send any requests. 234.It Fl staticarp 235If the Address Resolution Protocol is enabled, 236the host will perform normally, 237sending out requests and listening for replies. 238.It Cm broadcast 239(Inet only.) 240Specify the address to use to represent broadcasts to the 241network. 242The default broadcast address is the address with a host part of all 1's. 243.It Cm debug 244Enable driver dependent debugging code; usually, this turns on 245extra console error logging. 246.It Fl debug 247Disable driver dependent debugging code. 248.It Cm promisc 249Put interface into permanently promiscuous mode. 250.It Fl promisc 251Disable permanently promiscuous mode. 252.It Cm delete 253Another name for the 254.Fl alias 255parameter. 256.It Cm down 257Mark an interface 258.Dq down . 259When an interface is marked 260.Dq down , 261the system will not attempt to 262transmit messages through that interface. 263If possible, the interface will be reset to disable reception as well. 264This action does not automatically disable routes using the interface. 265.It Cm eui64 266(Inet6 only.) 267Fill interface index 268(lowermost 64bit of an IPv6 address) 269automatically. 270.It Cm ipdst 271This is used to specify an Internet host who is willing to receive 272IP packets encapsulating IPX packets bound for a remote network. 273An apparent point to point link is constructed, and 274the address specified will be taken as the IPX address and network 275of the destination. 276.It Cm media Ar type 277If the driver supports the media selection system, set the media type 278of the interface to 279.Ar type . 280Some interfaces support the mutually exclusive use of one of several 281different physical media connectors. 282For example, a 10Mbit/s Ethernet 283interface might support the use of either 284.Tn AUI 285or twisted pair connectors. 286Setting the media type to 287.Cm 10base5/AUI 288would change the currently active connector to the AUI port. 289Setting it to 290.Cm 10baseT/UTP 291would activate twisted pair. 292Refer to the interfaces' driver 293specific documentation or man page for a complete list of the 294available types. 295.It Cm mediaopt Ar opts 296If the driver supports the media selection system, set the specified 297media options on the interface. 298The 299.Ar opts 300argument 301is a comma delimited list of options to apply to the interface. 302Refer to the interfaces' driver specific man page for a complete 303list of available options. 304.It Fl mediaopt Ar opts 305If the driver supports the media selection system, disable the 306specified media options on the interface. 307.It Cm mode Ar mode 308If the driver supports the media selection system, set the specified 309operating mode on the interface to 310.Ar mode . 311For IEEE 802.11 wireless interfaces that support multiple operating modes 312this directive is used to select between 802.11a 313.Pq Cm 11a , 314802.11b 315.Pq Cm 11b , 316and 802.11g 317.Pq Cm 11g 318operating modes. 319.It Cm name Ar name 320Set the interface name to 321.Ar name . 322.It Cm rss 323If the driver supports receive side scaling, 324enable receive side scaling on the interface. 325.It Fl rss 326If the driver supports receive side scaling, 327disable receive side scaling on the interface. 328.It Cm rxcsum , txcsum 329If the driver supports user-configurable checksum offloading, 330enable receive (or transmit) checksum offloading on the interface. 331Some drivers may not be able to enable these flags independently 332of each other, so setting one may also set the other. 333The driver will offload as much checksum work as it can reliably 334support, the exact level of offloading varies between drivers. 335.It Fl rxcsum , txcsum 336If the driver supports user-configurable checksum offloading, 337disable receive (or transmit) checksum offloading on the interface. 338These settings may not always be independent of each other. 339.It Cm tso 340If the driver supports TCP segmentation offloading, 341enable TCP segmentation offloading on the interface. 342.It Fl tso 343If the driver supports TCP segmentation offloading, 344disable TCP segmentation offloading on the interface. 345.It Cm vlanmtu , vlanhwtag 346If the driver offers user-configurable VLAN support, enable 347reception of extended frames or tag processing in hardware, 348respectively. 349Note that this must be issued on a physical interface associated with 350.Xr vlan 4 , 351not on a 352.Xr vlan 4 353interface itself. 354.It Fl vlanmtu , vlanhwtag 355If the driver offers user-configurable VLAN support, disable 356reception of extended frames or tag processing in hardware, 357respectively. 358.It Cm pollcpu Ar cpu 359Turn on 360.Xr polling 4 361feature and disable interrupts on the interface, 362if the driver supports this mode and 363.Ar cpu 364supports 365.Xr polling 4 . 366Driver will be polled by 367.Ar cpu . 368.It Cm polling 369Turn on 370.Xr polling 4 371feature and disable interrupts on the interface, if the driver supports 372this mode. 373.It Fl polling 374Turn off 375.Xr polling 4 376feature and enable interrupt mode on the interface. 377.It Cm create 378Create the specified network pseudo-device. 379If the interface is given without a unit number, try to create a new 380device with an arbitrary unit number. 381If creation of an arbitrary device is successful, the new device name is 382printed to standard output unless the interface is renamed or destroyed 383in the same 384.Nm 385invocation. 386.It Cm destroy 387Destroy the specified network pseudo-device. 388.It Cm plumb 389Another name for the 390.Cm create 391parameter. 392Included for 393.Tn Solaris 394compatibility. 395.It Cm unplumb 396Another name for the 397.Cm destroy 398parameter. 399Included for 400.Tn Solaris 401compatibility. 402.It Cm metric Ar n 403Set the routing metric of the interface to 404.Ar n , 405default 0. 406The routing metric is used by the routing protocol 407.Pq Xr routed 8 . 408Higher metrics have the effect of making a route 409less favorable; metrics are counted as additional hops 410to the destination network or host. 411.It Cm mtu Ar n 412Set the maximum transmission unit of the interface to 413.Ar n , 414default is interface specific. 415The MTU is used to limit the size of packets that are transmitted on an 416interface. 417Not all interfaces support setting the MTU, and some interfaces have 418range restrictions. 419.It Cm netmask Ar mask 420.\" (Inet and ISO.) 421(Inet only.) 422Specify how much of the address to reserve for subdividing 423networks into sub-networks. 424The mask includes the network part of the local address 425and the subnet part, which is taken from the host field of the address. 426The mask can be specified as a single hexadecimal number 427with a leading 428.Ql 0x , 429with a dot-notation Internet address, 430or with a pseudo-network name listed in the network table 431.Xr networks 5 . 432The mask contains 1's for the bit positions in the 32-bit address 433which are to be used for the network and subnet parts, 434and 0's for the host part. 435The mask should contain at least the standard network portion, 436and the subnet field should be contiguous with the network 437portion. 438.Pp 439The netmask can also be specified in CIDR notation after the address. 440See the 441.Ar address 442option above for more information. 443.It Cm autoconf 444(Inet6 only.) 445Enable autoconfiguration. 446.It Fl autoconf 447Disable autoconfiguration. 448.It Cm pltime Ar n 449(Inet6 only.) 450Set preferred lifetime for the address. 451.It Cm vltime Ar n 452(Inet6 only.) 453Set valid lifetime for the address. 454.It Cm prefixlen Ar len 455(Inet6 only.) 456Specify that 457.Ar len 458bits are reserved for subdividing networks into sub-networks. 459The 460.Ar len 461must be integer, and for syntactical reason it must be between 0 to 128. 462It is almost always 64 under the current IPv6 assignment rule. 463If the parameter is omitted, 64 is used. 464.Pp 465The prefix can also be specified using the slash notation after the address. 466See the 467.Ar address 468option above for more information. 469.It Cm deprecated 470(Inet6 only.) 471Set the IPv6 deprecated address bit. 472.It Fl deprecated 473(Inet6 only.) 474Clear the IPv6 deprecated address bit. 475.It Cm tentative 476(Inet6 only.) 477Set the IPv6 tentative address bit. 478.It Fl tentative 479(Inet6 only.) 480Clear the IPv6 tentative address bit. 481.\" see 482.\" Xr eon 5 . 483.\" .It Cm nsellength Ar n 484.\" .Pf ( Tn ISO 485.\" only) 486.\" This specifies a trailing number of bytes for a received 487.\" .Tn NSAP 488.\" used for local identification, the remaining leading part of which is 489.\" taken to be the 490.\" .Tn NET 491.\" (Network Entity Title). 492.\" The default value is 1, which is conformant to US 493.\" .Tn GOSIP . 494.\" When an ISO address is set in an ifconfig command, 495.\" it is really the 496.\" .Tn NSAP 497.\" which is being specified. 498.\" For example, in 499.\" .Tn US GOSIP , 500.\" 20 hex digits should be 501.\" specified in the 502.\" .Tn ISO NSAP 503.\" to be assigned to the interface. 504.\" There is some evidence that a number different from 1 may be useful 505.\" for 506.\" .Tn AFI 507.\" 37 type addresses. 508.It Cm range Ar netrange 509Under appletalk, set the interface to respond to a 510.Ar netrange 511of the form 512.Ar startnet Ns - Ns Ar endnet . 513Appletalk uses this scheme instead of 514netmasks though 515.Dx 516implements it internally as a set of netmasks. 517.It Cm remove 518Another name for the 519.Fl alias 520parameter. 521Introduced for compatibility 522with 523.Bsx . 524.It Cm phase 525The argument following this specifies the version (phase) of the 526Appletalk network attached to the interface. 527Values of 1 or 2 are permitted. 528.Sm off 529.It Cm link Op Cm 0 No - Cm 2 530.Sm on 531Enable special processing of the link level of the interface. 532These three options are interface specific in actual effect, however, 533they are in general used to select special modes of operation. 534An example 535of this is to enable SLIP compression, or to select the connector type 536for some Ethernet cards. 537Refer to the man page for the specific driver 538for more information. 539.Sm off 540.It Fl link Op Cm 0 No - Cm 2 541.Sm on 542Disable special processing at the link level with the specified interface. 543.It Cm compress 544Another name for the 545.Cm link0 546parameter. 547.It Cm normal 548Another name for the 549.Fl link0 550parameter. 551.It Cm noicmp 552Another name for the 553.Cm link1 554parameter. 555.It Cm monitor 556Put the interface in monitor mode. 557No packets are transmitted, and received packets are discarded after 558.Xr bpf 4 559processing. 560.It Fl monitor 561Take the interface out of monitor mode. 562.It Cm up 563Mark an interface 564.Dq up . 565This may be used to enable an interface after an 566.Dq Nm Cm down . 567It happens automatically when setting the first address on an interface. 568If the interface was reset when previously marked down, 569the hardware will be re-initialized. 570.El 571.Pp 572The following parameters are specific to cloning 573IEEE 802.11 wireless interfaces with the 574.Cm create 575request: 576.Bl -tag -width indent 577.It Cm wlandev Ar device 578Use 579.Ar device 580as the parent for the cloned device. 581.It Cm wlanmode Ar mode 582Specify the operating mode for this cloned device. 583.Ar mode 584is one of 585.Cm sta , 586.Cm ahdemo 587(or 588.Cm adhoc-demo ), 589.Cm ibss , 590(or 591.Cm adhoc ), 592.Cm ap , 593(or 594.Cm hostap ), 595.Cm wds , 596.Cm tdma , 597.Cm mesh , 598and 599.Cm monitor . 600The operating mode of a cloned interface cannot be changed. 601The 602.Cm tdma 603mode is actually implemented as an 604.Cm adhoc-demo 605interface with special properties. 606.It Cm wlanbssid Ar bssid 607The 802.11 mac address to use for the bssid. 608This must be specified at create time for a legacy 609.Cm wds 610device. 611.It Cm wlanaddr Ar address 612The local mac address. 613If this is not specified then a mac address will automatically be assigned 614to the cloned device. 615Typically this address is the same as the address of the parent device 616but if the 617.Cm bssid 618parameter is specified then the driver will craft a unique address for 619the device (if supported). 620.It Cm wdslegacy 621Mark a 622.Cm wds 623device as operating in ``legacy mode''. 624Legacy 625.Cm wds 626devices have a fixed peer relationship and do not, for example, roam 627if their peer stops communicating. 628For completeness a Dynamic WDS (DWDS) interface may marked as 629.Fl wdslegacy . 630.It Cm bssid 631Request a unique local mac address for the cloned device. 632This is only possible if the device supports multiple mac addresses. 633To force use of the parent's mac address use 634.Fl bssid . 635.It Cm beacons 636Mark the cloned interface as depending on hardware support to 637track received beacons. 638To have beacons tracked in software use 639.Fl beacons . 640For 641.Cm hostap 642mode 643.Fl beacons 644can also be used to indicate no beacons should 645be transmitted; this can be useful when creating a WDS configuration but 646.Cm wds 647interfaces can only be created as companions to an access point. 648.El 649.Pp 650The following parameters are specific to IEEE 802.11 wireless interfaces 651cloned with a 652.Cm create 653operation: 654.Bl -tag -width indent 655.It Cm ampdu 656Enable sending and receiving AMPDU frames when using 802.11n (default). 657The 802.11n specification states a compliant station must be capable 658of receiving AMPDU frames but transmission is optional. 659Use 660.Fl ampdu 661to disable all use of AMPDU with 802.11n. 662For testing and/or to work around interoperability problems one can use 663.Cm ampdutx 664and 665.Cm ampdurx 666to control use of AMPDU in one direction. 667.It Cm ampdudensity Ar density 668Set the AMPDU density parameter used when operating with 802.11n. 669This parameter controls the inter-packet gap for AMPDU frames. 670The sending device normally controls this setting but a receiving station 671may request wider gaps. 672Legal values for 673.Ar density 674are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds). 675A value of 676.Cm - 677is treated the same as 0. 678.It Cm ampdulimit Ar limit 679Set the limit on packet size for receiving AMPDU frames when operating 680with 802.11n. 681Legal values for 682.Ar limit 683are 8192, 16384, 32768, and 65536 but one can also specify 684just the unique prefix: 8, 16, 32, 64. 685Note the sender may limit the size of AMPDU frames to be less 686than the maximum specified by the receiving station. 687.It Cm amsdu 688Enable sending and receiving AMSDU frames when using 802.11n. 689By default AMSDU is received but not transmitted. 690Use 691.Fl amsdu 692to disable all use of AMSDU with 802.11n. 693For testing and/or to work around interoperability problems one can use 694.Cm amsdutx 695and 696.Cm amsdurx 697to control use of AMSDU in one direction. 698.It Cm amsdulimit Ar limit 699Set the limit on packet size for sending and receiving AMSDU frames 700when operating with 802.11n. 701Legal values for 702.Ar limit 703are 7935 and 3839 (bytes). 704Note the sender may limit the size of AMSDU frames to be less 705than the maximum specified by the receiving station. 706Note also that devices are not required to support the 7935 limit, 707only 3839 is required by the specification and the larger value 708may require more memory to be dedicated to support functionality 709that is rarely used. 710.It Cm apbridge 711When operating as an access point, pass packets between 712wireless clients directly (default). 713To instead let them pass up through the 714system and be forwarded using some other mechanism, use 715.Fl apbridge . 716Disabling the internal bridging 717is useful when traffic is to be processed with 718packet filtering. 719.It Cm authmode Ar mode 720Set the desired authentication mode in infrastructure mode. 721Not all adapters support all modes. 722The set of 723valid modes is 724.Cm none , open , shared 725(shared key), 726.Cm 8021x 727(IEEE 802.1x), 728and 729.Cm wpa 730(IEEE WPA/WPA2/802.11i). 731The 732.Cm 8021x 733and 734.Cm wpa 735modes are only useful when using an authentication service 736(a supplicant for client operation or an authenticator when 737operating as an access point). 738Modes are case insensitive. 739.It Cm bgscan 740Enable background scanning when operating as a station. 741Background scanning is a technique whereby a station associated to 742an access point will temporarily leave the channel to scan for 743neighboring stations. 744This allows a station to maintain a cache of nearby access points 745so that roaming between access points can be done without 746a lengthy scan operation. 747Background scanning is done only when a station is not busy and 748any outbound traffic will cancel a scan operation. 749Background scanning should never cause packets to be lost though 750there may be some small latency if outbound traffic interrupts a 751scan operation. 752By default background scanning is enabled if the device is capable. 753To disable background scanning, use 754.Fl bgscan . 755Background scanning is controlled by the 756.Cm bgscanidle 757and 758.Cm bgscanintvl 759parameters. 760Background scanning must be enabled for roaming; this is an artifact 761of the current implementation and may not be required in the future. 762.It Cm bgscanidle Ar idletime 763Set the minimum time a station must be idle (not transmitting or 764receiving frames) before a background scan is initiated. 765The 766.Ar idletime 767parameter is specified in milliseconds. 768By default a station must be idle at least 250 milliseconds before 769a background scan is initiated. 770The idle time may not be set to less than 100 milliseconds. 771.It Cm bgscanintvl Ar interval 772Set the interval at which background scanning is attempted. 773The 774.Ar interval 775parameter is specified in seconds. 776By default a background scan is considered every 300 seconds (5 minutes). 777The 778.Ar interval 779may not be set to less than 15 seconds. 780.It Cm bintval Ar interval 781Set the interval at which beacon frames are sent when operating in 782ad-hoc or ap mode. 783The 784.Ar interval 785parameter is specified in TU's (1024 usecs). 786By default beacon frames are transmitted every 100 TU's. 787.It Cm bmissthreshold Ar count 788Set the number of consecutive missed beacons at which the station 789will attempt to roam (i.e., search for a new access point). 790The 791.Ar count 792parameter must be in the range 1 to 255; though the 793upper bound may be reduced according to device capabilities. 794The default threshold is 7 consecutive missed beacons; but 795this may be overridden by the device driver. 796Another name for the 797.Cm bmissthreshold 798parameter is 799.Cm bmiss . 800.It Cm bssid Ar address 801Specify the MAC address of the access point to use when operating 802as a station in a BSS network. 803This overrides any automatic selection done by the system. 804To disable a previously selected access point, supply 805.Cm any , none , 806or 807.Cm - 808for the address. 809This option is useful when more than one access point uses the same SSID. 810Another name for the 811.Cm bssid 812parameter is 813.Cm ap . 814.It Cm burst 815Enable packet bursting. 816Packet bursting is a transmission technique whereby the wireless 817medium is acquired once to send multiple frames and the interframe 818spacing is reduced. 819This technique can significantly increase throughput by reducing 820transmission overhead. 821Packet bursting is supported by the 802.11e QoS specification 822and some devices that do not support QoS may still be capable. 823By default packet bursting is enabled if a device is capable 824of doing it. 825To disable packet bursting, use 826.Fl burst . 827.It Cm chanlist Ar channels 828Set the desired channels to use when scanning for access 829points, neighbors in an IBSS network, or looking for unoccupied 830channels when operating as an access point. 831The set of channels is specified as a comma-separated list with 832each element in the list representing either a single channel number or a range 833of the form 834.Dq Li a-b . 835Channel numbers must be in the range 1 to 255 and be permissible 836according to the operating characteristics of the device. 837.It Cm channel Ar number 838Set a single desired channel. 839Channels range from 1 to 255, but the exact selection available 840depends on the region your adaptor was manufactured for. 841Setting 842the channel to 843.Li any , 844or 845.Cm - 846will clear any desired channel and, if the device is marked up, 847force a scan for a channel to operate on. 848Alternatively the frequency, in megahertz, may be specified 849instead of the channel number. 850.Pp 851When there are several ways to use a channel the channel 852number/frequency may be appended with attributes to clarify. 853For example, if a device is capable of operating on channel 6 854with 802.11n and 802.11g then one can specify that g-only use 855should be used by specifying ``6:g''. 856Similarly the channel width can be specified by appending it 857with ``/''; e.g. ``6/40'' specifies a 40MHz wide channel, 858These attributes can be combined as in: ``6:ht/40''. 859The full set of flags specified following a `:'' are: 860.Cm a 861(802.11a), 862.Cm b 863(802.11b), 864.Cm d 865(Atheros Dynamic Turbo mode), 866.Cm g 867(802.11g), 868.Cm h 869or 870.Cm n 871(802.11n aka HT), 872.Cm s 873(Atheros Static Turbo mode), 874and 875.Cm t 876(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt''). 877The full set of channel widths following a '/' are: 878.Cm 5 879(5MHz aka quarter-rate channel), 880.Cm 10 881(10MHz aka half-rate channel), 882.Cm 20 883(20MHz mostly for use in specifying ht20), 884and 885.Cm 40 886(40MHz mostly for use in specifying ht40), 887In addition, 888a 40MHz HT channel specification may include the location 889of the extension channel by appending ``+'' or ``-'' for above and below, 890respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation 891with the center channel at frequency 2437 and the extension channel above. 892.It Cm country Ar name 893Set the country code to use in calculating the regulatory constraints 894for operation. 895In particular the set of available channels, how the wireless device 896will operation on the channels, and the maximum transmit power that 897can be used on a channel are defined by this setting. 898Country/Region codes are specified as a 2-character abbreviation 899defined by ISO 3166 or using a longer, but possibly ambiguous, spelling; 900e.g. "ES" and "Spain". 901The set of country codes are taken from /etc/regdomain.xml and can also 902be viewed with the ``list countries'' request. 903Note that not all devices support changing the country code from a default 904setting; typically stored in EEPROM. 905See also 906.Cm regdomain , 907.Cm indoor , 908.Cm outdoor , 909and 910.Cm anywhere . 911.It Cm dfs 912Enable Dynamic Frequency Selection (DFS) as specified in 802.11h. 913DFS embodies several facilities including detection of overlapping 914radar signals, dynamic transmit power control, and channel selection 915according to a least-congested criteria. 916DFS support is mandatory for some 5Ghz frequencies in certain 917locales (e.g. ETSI). 918By default DFS is enabled according to the regulatory definitions 919specified in /etc/regdomain.xml and the curent country code, regdomain, 920and channel. 921Note the underlying device (and driver) must support radar detection 922for full DFS support to work. 923To be fully compliant with the local regulatory agency frequencies that 924require DFS should not be used unless it is fully supported. 925Use 926.Fl dfs 927to disable this functionality for testing. 928.It Cm dotd 929Enable support for the 802.11d specification (default). 930When this support is enabled in station mode, beacon frames that advertise 931a country code different than the currently configured country code will 932cause an event to be dispatched to user applications. 933This event can be used by the station to adopt that country code and 934operate according to the associated regulatory constraints. 935When operating as an access point with 802.11d enabled the beacon and 936probe response frames transmitted will advertise the current regulatory 937domain settings. 938To disable 802.11d use 939.Fl dotd . 940.It Cm doth 941Enable 802.11h support including spectrum management. 942When 802.11h is enabled beacon and probe response frames will have 943the SpectrumMgt bit set in the capabilities field and 944country and power constraint information elements will be present. 945802.11h support also includes handling Channel Switch Announcements (CSA) 946which are a mechanism to coordinate channel changes by an access point. 947By default 802.11h is enabled if the device is capable. 948To disable 802.11h use 949.Fl doth . 950.It Cm deftxkey Ar index 951Set the default key to use for transmission. 952Typically this is only set when using WEP encryption. 953Note that you must set a default transmit key 954for the system to know which key to use in encrypting outbound traffic. 955The 956.Cm weptxkey 957is an alias for this request; it is provided for backwards compatibility. 958.It Cm dtimperiod Ar period 959Set the 960DTIM 961period for transmitting buffered multicast data frames when 962operating in ap mode. 963The 964.Ar period 965specifies the number of beacon intervals between DTIM 966and must be in the range 1 to 15. 967By default DTIM is 1 (i.e., DTIM occurs at each beacon). 968.It Cm dturbo 969Enable the use of Atheros Dynamic Turbo mode when communicating with 970another Dynamic Turbo-capable station. 971Dynamic Turbo mode is an Atheros-specific mechanism by which 972stations switch between normal 802.11 operation and a ``boosted'' 973mode in which a 40MHz wide channel is used for communication. 974Stations using Dynamic Turbo mode operate boosted only when the 975channel is free of non-dturbo stations; when a non-dturbo station 976is identified on the channel all stations will automatically drop 977back to normal operation. 978By default, Dynamic Turbo mode is not enabled, even if the device is capable. 979Note that turbo mode (dynamic or static) is only allowed on some 980channels depending on the regulatory constraints; use the 981.Cm list chan 982command to identify the channels where turbo mode may be used. 983To disable Dynamic Turbo mode use 984.Fl dturbo . 985.It Cm dwds 986Enable Dynamic WDS (DWDS) support. 987DWDS is a facility by which 4-address traffic can be carried between 988stations operating in infrastructure mode. 989A station first associates to an access point and authenticates using 990normal procedures (e.g. WPA). 991Then 4-address frames are passed to carry traffic for stations 992operating on either side of the wireless link. 993DWDS extends the normal WDS mechanism by leveraging existing security 994protocols and eliminating static binding. 995.Pp 996When DWDS is enabled on an access point 4-address frames received from 997an authorized station will generate a ``DWDS discovery'' event to user 998applications. 999This event should be used to create a WDS interface that is bound 1000to the remote station (and usually plumbed into a bridge). 1001Once the WDS interface is up and running 4-address traffic then logically 1002flows through that interface. 1003.Pp 1004When DWDS is enabled on a station, traffic with a destination address 1005different from the peer station are encapsulated in a 4-address frame 1006and transmitted to the peer. 1007All 4-address traffic uses the security information of the stations 1008(e.g. cryptographic keys). 1009A station is associated using 802.11n facilities may transport 10104-address traffic using these same mechanisms; this depends on available 1011resources and capabilities of the device. 1012The DWDS implementation guards against layer 2 routing loops of 1013multicast traffic. 1014.It Cm ff 1015Enable the use of Atheros Fast Frames when communicating with 1016another Fast Frames-capable station. 1017Fast Frames are an encapsulation technique by which two 802.3 1018frames are transmitted in a single 802.11 frame. 1019This can noticeably improve throughput but requires that the 1020receiving station understand how to decapsulate the frame. 1021Fast frame use is negotiated using the Atheros 802.11 vendor-specific 1022protocol extension so enabling use is safe when communicating with 1023non-Atheros devices. 1024By default, use of fast frames is enabled if the device is capable. 1025To explicitly disable fast frames, use 1026.Fl ff . 1027.It Cm fragthreshold Ar length 1028Set the threshold for which transmitted frames are broken into fragments. 1029The 1030.Ar length 1031argument is the frame size in bytes and must be in the range 256 to 2346. 1032Setting 1033.Ar length 1034to 1035.Li 2346 , 1036.Cm any , 1037or 1038.Cm - 1039disables transmit fragmentation. 1040Not all adapters honor the fragmentation threshold. 1041.It Cm hidessid 1042When operating as an access point, do not broadcast the SSID 1043in beacon frames or respond to probe request frames unless 1044they are directed to the ap (i.e., they include the ap's SSID). 1045By default, the SSID is included in beacon frames and 1046undirected probe request frames are answered. 1047To re-enable the broadcast of the SSID etc., use 1048.Fl hidessid . 1049.It Cm ht 1050Enable use of High Throughput (HT) when using 802.11n (default). 1051The 802.11n specification includes mechanisms for operation 1052on 20MHz and 40MHz wide channels using different signalling mechanisms 1053than specified in 802.11b, 802.11g, and 802.11a. 1054Stations negotiate use of these facilities, termed HT20 and HT40, 1055when they associate. 1056To disable all use of 802.11n use 1057.Fl ht . 1058To disable use of HT20 (e.g. to force only HT40 use) use 1059.Fl ht20 . 1060To disable use of HT40 use 1061.Fl ht40 . 1062.Pp 1063HT configuration is used to ``auto promote'' operation 1064when several choices are available. 1065For example, if a station associates to an 11n-capable access point 1066it controls whether the station uses legacy operation, HT20, or HT40. 1067When an 11n-capable device is setup as an access point and 1068Auto Channel Selection is used to locate a channel to operate on, 1069HT configuration controls whether legacy, HT20, or HT40 operation is setup 1070on the selected channel. 1071If a fixed channel is specified for a station then HT configuration can 1072be given as part of the channel specification; e.g. 6:ht/20 to setup 1073HT20 operation on channel 6. 1074.It Cm htcompat 1075Enable use of compatibility support for pre-802.11n devices (default). 1076The 802.11n protocol specification went through several incompatible iterations. 1077Some vendors implemented 11n support to older specifications that 1078will not interoperate with a purely 11n-compliant station. 1079In particular the information elements included in management frames 1080for old devices are different. 1081When compatibility support is enabled both standard and compatible data 1082will be provided. 1083Stations that associate using the compatibility mechanisms are flagged 1084in ``list sta''. 1085To disable compatibility support use 1086.Fl htcompat . 1087.It Cm htprotmode Ar technique 1088For interfaces operating in 802.11n, use the specified 1089.Ar technique 1090for protecting HT frames in a mixed legacy/HT network. 1091The set of valid techniques is 1092.Cm off , 1093and 1094.Cm rts 1095(RTS/CTS, default). 1096Technique names are case insensitive. 1097.It Cm inact 1098Enable inactivity processing for stations associated to an 1099access point (default). 1100When operating as an access point the 802.11 layer monitors 1101the activity of each associated station. 1102When a station is inactive for 5 minutes it will send several 1103``probe frames'' to see if the station is still present. 1104If no response is received then the station is deauthenticated. 1105Applications that prefer to handle this work can disable this 1106facility by using 1107.Fl inact . 1108.It Cm indoor 1109Set the location to use in calculating regulatory constraints. 1110The location is also advertised in beacon and probe response frames 1111when 802.11d is enabled with 1112.Cm dotd . 1113See also 1114.Cm outdoor , 1115.Cm anywhere , 1116.Cm country , 1117and 1118.Cm regdomain . 1119.It Cm list active 1120Display the list of channels available for use taking into account 1121any restrictions set with the 1122.Cm chanlist 1123directive. 1124See the description of 1125.Cm list chan 1126for more information. 1127.It Cm list caps 1128Display the adaptor's capabilities, including the operating 1129modes supported. 1130.It Cm list chan 1131Display the list of channels available for use. 1132Channels are shown with their IEEE channel number, equivalent 1133frequency, and usage modes. 1134Channels identified as 1135.Ql 11g 1136are also usable in 1137.Ql 11b 1138mode. 1139Channels identified as 1140.Ql 11a Turbo 1141may be used only for Atheros' Static Turbo mode 1142(specified with 1143.Cm mediaopt turbo ) . 1144Channels marked with a 1145.Ql * 1146have a regulatory constraint that they be passively scanned. 1147This means a station is not permitted to transmit on the channel until 1148it identifies the channel is being used for 802.11 communication; 1149typically by hearing a beacon frame from an access point operating 1150on the channel. 1151.Cm list freq 1152is another way of requesting this information. 1153By default a compacted list of channels is displayed; if the 1154.Fl v 1155option is specified then all channels are shown. 1156.It Cm list countries 1157Display the set of country codes and regulatory domains that can be 1158used in regulatory configuration. 1159.It Cm list mac 1160Display the current MAC Access Control List state. 1161Each address is prefixed with a character that indicates the 1162current policy applied to it: 1163.Ql + 1164indicates the address is allowed access, 1165.Ql - 1166indicates the address is denied access, 1167.Ql * 1168indicates the address is present but the current policy open 1169(so the ACL is not consulted). 1170.It Cm list mesh 1171Displays the mesh routing table, used for forwarding packets on a mesh 1172network. 1173.It Cm list regdomain 1174Display the current regulatory settings including the available channels 1175and transmit power caps. 1176.It Cm list roam 1177Display the parameters that govern roaming operation. 1178.It Cm list txparam 1179Display the parameters that govern transmit operation. 1180.It Cm list txpower 1181Display the transmit power caps for each channel. 1182.It Cm list scan 1183Display the access points and/or ad-hoc neighbors 1184located in the vicinity. 1185This information may be updated automatically by the adapter 1186with a 1187.Cm scan 1188request or through background scanning. 1189Depending on the capabilities of the stations the following 1190flags can be included in the output: 1191.Bl -tag -width 3n 1192.It Li A 1193Authorized. 1194Indicates that the station is permitted to send/receive data frames. 1195.It Li E 1196Extended Rate Phy (ERP). 1197Indicates that the station is operating in an 802.11g network 1198using extended transmit rates. 1199.It Li H 1200High Throughput (HT). 1201Indicates that the station is using HT transmit rates. 1202If a `+' follows immediately after then the station associated 1203using deprecated mechanisms supported only when 1204.Cm htcompat 1205is enabled. 1206.It Li P 1207Power Save. 1208Indicates that the station is operating in power save mode. 1209.It Li Q 1210Quality of Service (QoS). 1211Indicates that the station is using QoS encapsulation for 1212data frame. 1213QoS encapsulation is enabled only when WME mode is enabled. 1214.It Li T 1215Transitional Security Network (TSN). 1216Indicates that the station associated using TSN; see also 1217.Cm tsn 1218below. 1219.It Li W 1220Wi-Fi Protected Setup (WPS). 1221Indicates that the station associated using WPS. 1222.El 1223.Pp 1224By default interesting information elements captured from the neighboring 1225stations are displayed at the end of each row. 1226Possible elements include: 1227.Cm WME 1228(station supports WME), 1229.Cm WPA 1230(station supports WPA), 1231.Cm WPS 1232(station supports WPS), 1233.Cm RSN 1234(station supports 802.11i/RSN), 1235.Cm HTCAP 1236(station supports 802.11n/HT communication), 1237.Cm ATH 1238(station supports Atheros protocol extensions), 1239.Cm VEN 1240(station supports unknown vendor-specific extensions). 1241If the 1242.Fl v 1243flag is used all the information elements and their 1244contents will be shown. 1245Specifying the 1246.Fl v 1247flag also enables display of long SSIDs. 1248The 1249.Cm list ap 1250command is another way of requesting this information. 1251.It Cm list sta 1252When operating as an access point display the stations that are 1253currently associated. 1254When operating in ad-hoc mode display stations identified as 1255neighbors in the IBSS. 1256When operating in mesh mode display stations identified as 1257neighbors in the MBSS. 1258When operating in station mode display the access point. 1259Capabilities advertised by the stations are described under 1260the 1261.Cm scan 1262request. 1263Depending on the capabilities of the stations the following 1264flags can be included in the output: 1265.Bl -tag -width 3n 1266.It Li A 1267Authorized. 1268Indicates that the station is permitted to send/receive data frames. 1269.It Li E 1270Extended Rate Phy (ERP). 1271Indicates that the station is operating in an 802.11g network 1272using extended transmit rates. 1273.It Li H 1274High Throughput (HT). 1275Indicates that the station is using HT transmit rates. 1276If a `+' follows immediately after then the station associated 1277using deprecated mechanisms supported only when 1278.Cm htcompat 1279is enabled. 1280.It Li P 1281Power Save. 1282Indicates that the station is operating in power save mode. 1283.It Li Q 1284Quality of Service (QoS). 1285Indicates that the station is using QoS encapsulation for 1286data frame. 1287QoS encapsulation is enabled only when WME mode is enabled. 1288.It Li T 1289Transitional Security Network (TSN). 1290Indicates that the station associated using TSN; see also 1291.Cm tsn 1292below. 1293.It Li W 1294Wi-Fi Protected Setup (WPS). 1295Indicates that the station associated using WPS. 1296.El 1297.Pp 1298By default information elements received from associated stations 1299are displayed in a short form; the 1300.Fl v 1301flag causes this information to be displayed symbolically. 1302.It Cm list wme 1303Display the current channel parameters to use when operating in WME mode. 1304If the 1305.Fl v 1306option is specified then both channel and BSS parameters are displayed 1307for each AC (first channel, then BSS). 1308When WME mode is enabled for an adaptor this information will be 1309displayed with the regular status; this command is mostly useful 1310for examining parameters when WME mode is disabled. 1311See the description of the 1312.Cm wme 1313directive for information on the various parameters. 1314.It Cm maxretry Ar count 1315Set the maximum number of tries to use in sending unicast frames. 1316The default setting is 6 but drivers may override this with a value 1317they choose. 1318.It Cm mcastrate Ar rate 1319Set the rate for transmitting multicast/broadcast frames. 1320Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1321This rate should be valid for the current operating conditions; 1322if an invalid rate is specified drivers are free to chose an 1323appropriate rate. 1324.It Cm mgtrate Ar rate 1325Set the rate for transmitting management and/or control frames. 1326Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1327.It Cm outdoor 1328Set the location to use in calculating regulatory constraints. 1329The location is also advertised in beacon and probe response frames 1330when 802.11d is enabled with 1331.Cm dotd . 1332See also 1333.Cm anywhere , 1334.Cm country , 1335.Cm indoor , 1336and 1337.Cm regdomain . 1338.It Cm powersave 1339Enable powersave operation. 1340When operating as a client, the station will conserve power by 1341periodically turning off the radio and listening for 1342messages from the access point telling it there are packets waiting. 1343The station must then retrieve the packets. 1344Not all devices support power save operation as a client. 1345The 802.11 specification requires that all access points support 1346power save but some drivers do not. 1347Use 1348.Fl powersave 1349to disable powersave operation when operating as a client. 1350.It Cm powersavemode Ar mode 1351Set powersave mode. 1352The set of valid modes is 1353.Cm off 1354(same as 1355.Fl powersave ) , 1356.Cm on 1357(same as 1358.Cm powersave ) , 1359and 1360.Cm cam 1361(same as 1362.Cm powersave ) . 1363.It Cm powersavesleep Ar sleep 1364Set the desired max powersave sleep time in TU's (1024 usecs). 1365By default the max powersave sleep time is 100 TU's. 1366.It Cm protmode Ar technique 1367For interfaces operating in 802.11g, use the specified 1368.Ar technique 1369for protecting OFDM frames in a mixed 11b/11g network. 1370The set of valid techniques is 1371.Cm off , cts 1372(CTS to self), 1373and 1374.Cm rtscts 1375(RTS/CTS). 1376Technique names are case insensitive. 1377Not all devices support 1378.Cm cts 1379as a protection technique. 1380.It Cm pureg 1381When operating as an access point in 802.11g mode allow only 138211g-capable stations to associate (11b-only stations are not 1383permitted to associate). 1384To allow both 11g and 11b-only stations to associate, use 1385.Fl pureg . 1386.It Cm puren 1387When operating as an access point in 802.11n mode allow only 1388HT-capable stations to associate (legacy stations are not 1389permitted to associate). 1390To allow both HT and legacy stations to associate, use 1391.Fl puren . 1392.It Cm regdomain Ar sku 1393Set the regulatory domain to use in calculating the regulatory constraints 1394for operation. 1395In particular the set of available channels, how the wireless device 1396will operation on the channels, and the maximum transmit power that 1397can be used on a channel are defined by this setting. 1398Regdomain codes (SKU's) are taken from /etc/regdomain.xml and can also 1399be viewed with the ``list countries'' request. 1400Note that not all devices support changing the regdomain from a default 1401setting; typically stored in EEPROM. 1402See also 1403.Cm country , 1404.Cm indoor , 1405.Cm outdoor , 1406and 1407.Cm anywhere . 1408.It Cm rifs 1409Enable use of Reduced InterFrame Spacing (RIFS) when operating in 802.11n 1410on an HT channel. 1411Note that RIFS must be supported by both the station and access point 1412for it to be used. 1413To disable RIFS use 1414.Fl rifs . 1415.It Cm roam:rate Ar rate 1416Set the threshold for controlling roaming when operating in a BSS. 1417The 1418.Ar rate 1419parameter specifies the transmit rate in megabits 1420at which roaming should be considered. 1421If the current transmit rate 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 rate threshold; the default values are: 143012 Mb/s (11a), 2 Mb/s (11b), 2 Mb/s (11g), MCS 1 (11na, 11ng). 1431.It Cm roam:rssi Ar rssi 1432Set the threshold for controlling roaming when operating in a BSS. 1433The 1434.Ar rssi 1435parameter specifies the receive signal strength in dBm units 1436at which roaming should be considered. 1437If the current rssi drops below this setting and background scanning 1438is enabled, then the system will check if a more desirable access point is 1439available and switch over to it. 1440The current scan cache contents are used if they are considered 1441valid according to the 1442.Cm scanvalid 1443parameter; otherwise a background scan operation is triggered before 1444any selection occurs. 1445Each channel type has a separate rssi threshold; the default values are 1446all 7 dBm. 1447.It Cm roaming Ar mode 1448When operating as a station, control how the system will 1449behave when communication with the current access point 1450is broken. 1451The 1452.Ar mode 1453argument may be one of 1454.Cm device 1455(leave it to the hardware device to decide), 1456.Cm auto 1457(handle either in the device or the operating system\[em]as appropriate), 1458.Cm manual 1459(do nothing until explicitly instructed). 1460By default, the device is left to handle this if it is 1461capable; otherwise, the operating system will automatically 1462attempt to reestablish communication. 1463Manual mode is used by applications such as 1464.Xr wpa_supplicant 8 1465that want to control the selection of an access point. 1466.It Cm rtsthreshold Ar length 1467Set the threshold for which 1468transmitted frames are preceded by transmission of an 1469RTS 1470control frame. 1471The 1472.Ar length 1473argument 1474is the frame size in bytes and must be in the range 1 to 2346. 1475Setting 1476.Ar length 1477to 1478.Li 2346 , 1479.Cm any , 1480or 1481.Cm - 1482disables transmission of RTS frames. 1483Not all adapters support setting the RTS threshold. 1484.It Cm scan 1485Initiate a scan of neighboring stations, wait for it to complete, and 1486display all stations found. 1487Only the super-user can initiate a scan. 1488See 1489.Cm list scan 1490for information on the display. 1491By default a background scan is done; otherwise a foreground 1492scan is done and the station may roam to a different access point. 1493The 1494.Cm list scan 1495request can be used to show recent scan results without 1496initiating a new scan. 1497.It Cm scanvalid Ar threshold 1498Set the maximum time the scan cache contents are considered valid; 1499i.e. will be used without first triggering a scan operation to 1500refresh the data. 1501The 1502.Ar threshold 1503parameter is specified in seconds and defaults to 60 seconds. 1504The minimum setting for 1505.Ar threshold 1506is 10 seconds. 1507One should take care setting this threshold; if it is set too low 1508then attempts to roam to another access point may trigger unnecessary 1509background scan operations. 1510.It Cm shortgi 1511Enable use of Short Guard Interval when operating in 802.11n 1512on an HT channel. 1513NB: this currently enables Short GI on both HT40 and HT20 channels. 1514To disable Short GI use 1515.Fl shortgi . 1516.It Cm smps 1517Enable use of Static Spatial Multiplexing Power Save (SMPS) 1518when operating in 802.11n. 1519A station operating with Static SMPS maintains only a single 1520receive chain active (this can significantly reduce power consumption). 1521To disable SMPS use 1522.Fl smps . 1523.It Cm smpsdyn 1524Enable use of Dynamic Spatial Multiplexing Power Save (SMPS) 1525when operating in 802.11n. 1526A station operating with Dynamic SMPS maintains only a single 1527receive chain active but switches to multiple receive chains when it 1528receives an RTS frame (this can significantly reduce power consumption). 1529Note that stations cannot distinguish between RTS/CTS intended to 1530enable multiple receive chains and those used for other purposes. 1531To disable SMPS use 1532.Fl smps . 1533.It Cm ssid Ar ssid 1534Set the desired Service Set Identifier (aka network name). 1535The SSID is a string up to 32 characters 1536in length and may be specified as either a normal string or in 1537hexadecimal when preceded by 1538.Ql 0x . 1539Additionally, the SSID may be cleared by setting it to 1540.Ql - . 1541.It Cm tdmaslot Ar slot 1542When operating with TDMA, use the specified 1543.Ar slot 1544configuration. 1545The 1546.Ar slot 1547is a number between 0 and the maximum number of slots in the BSS. 1548Note that a station configured as slot 0 is a master and 1549will broadcast beacon frames advertising the BSS; 1550stations configured to use other slots will always 1551scan to locate a master before they ever transmit. 1552By default 1553.Cm tdmaslot 1554is set to 1. 1555.It Cm tdmaslotcnt Ar cnt 1556When operating with TDMA, setup a BSS with 1557.Ar cnt 1558slots. 1559The slot count may be at most 8. 1560The current implementation is only tested with two stations 1561(i.e. point to point applications). 1562This setting is only meaningful when a station is configured as slot 0; 1563other stations adopt this setting from the BSS they join. 1564By default 1565.Cm tdmaslotcnt 1566is set to 2. 1567.It Cm tdmaslotlen Ar len 1568When operating with TDMA, setup a BSS such that each station has a slot 1569.Ar len 1570microseconds long. 1571The slot length must be at least 150 microseconds (1/8 TU) 1572and no more than 65 milliseconds. 1573Note that setting too small a slot length may result in poor channel 1574bandwidth utilization due to factors such as timer granularity and 1575guard time. 1576This setting is only meaningful when a station is configured as slot 0; 1577other stations adopt this setting from the BSS they join. 1578By default 1579.Cm tdmaslotlen 1580is set to 10 milliseconds. 1581.It Cm tdmabintval Ar intval 1582When operating with TDMA, setup a BSS such that beacons are transmitted every 1583.Ar intval 1584superframes to synchronize the TDMA slot timing. 1585A superframe is defined as the number of slots times the slot length; e.g. 1586a BSS with two slots of 10 milliseconds has a 20 millisecond superframe. 1587The beacon interval may not be zero. 1588A lower setting of 1589.Cm tdmabintval 1590causes the timers to be resynchronized more often; this can be help if 1591significant timer drift is observed. 1592By default 1593.Cm tdmabintval 1594is set to 5. 1595.It Cm tsn 1596When operating as an access point with WPA/802.11i allow legacy 1597stations to associate using static key WEP and open authentication. 1598To disallow legacy station use of WEP, use 1599.Fl tsn . 1600.It Cm txpower Ar power 1601Set the power used to transmit frames. 1602The 1603.Ar power 1604argument is specified in .5 dBm units. 1605Out of range values are truncated. 1606Typically only a few discreet power settings are available and 1607the driver will use the setting closest to the specified value. 1608Not all adapters support changing the transmit power. 1609.It Cm ucastrate Ar rate 1610Set a fixed rate for transmitting unicast frames. 1611Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1612This rate should be valid for the current operating conditions; 1613if an invalid rate is specified drivers are free to chose an 1614appropriate rate. 1615.It Cm wepmode Ar mode 1616Set the desired WEP mode. 1617Not all adapters support all modes. 1618The set of valid modes is 1619.Cm off , on , 1620and 1621.Cm mixed . 1622The 1623.Cm mixed 1624mode explicitly tells the adaptor to allow association with access 1625points which allow both encrypted and unencrypted traffic. 1626On these adapters, 1627.Cm on 1628means that the access point must only allow encrypted connections. 1629On other adapters, 1630.Cm on 1631is generally another name for 1632.Cm mixed . 1633Modes are case insensitive. 1634.It Cm weptxkey Ar index 1635Set the WEP key to be used for transmission. 1636This is the same as setting the default transmission key with 1637.Cm deftxkey . 1638.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 1639Set the selected WEP key. 1640If an 1641.Ar index 1642is not given, key 1 is set. 1643A WEP key will be either 5 or 13 1644characters (40 or 104 bits) depending of the local network and the 1645capabilities of the adaptor. 1646It may be specified either as a plain 1647string or as a string of hexadecimal digits preceded by 1648.Ql 0x . 1649For maximum portability, hex keys are recommended; 1650the mapping of text keys to WEP encryption is usually driver-specific. 1651In particular, the 1652.Tn Windows 1653drivers do this mapping differently to 1654.Fx . 1655A key may be cleared by setting it to 1656.Ql - . 1657If WEP is supported then there are at least four keys. 1658Some adapters support more than four keys. 1659If that is the case, then the first four keys 1660(1-4) will be the standard temporary keys and any others will be adaptor 1661specific keys such as permanent keys stored in NVRAM. 1662.Pp 1663Note that you must set a default transmit key with 1664.Cm deftxkey 1665for the system to know which key to use in encrypting outbound traffic. 1666.It Cm wme 1667Enable Wireless Multimedia Extensions (WME) support, if available, 1668for the specified interface. 1669WME is a subset of the IEEE 802.11e standard to support the 1670efficient communication of realtime and multimedia data. 1671To disable WME support, use 1672.Fl wme . 1673Another name for this parameter is 1674.Cm wmm . 1675.Pp 1676The following parameters are meaningful only when WME support is in use. 1677Parameters are specified per-AC (Access Category) and 1678split into those that are used by a station when acting 1679as an access point and those for client stations in the BSS. 1680The latter are received from the access point and may not be changed 1681(at the station). 1682The following Access Categories are recognized: 1683.Pp 1684.Bl -tag -width ".Cm AC_BK" -compact 1685.It Cm AC_BE 1686(or 1687.Cm BE ) 1688best effort delivery, 1689.It Cm AC_BK 1690(or 1691.Cm BK ) 1692background traffic, 1693.It Cm AC_VI 1694(or 1695.Cm VI ) 1696video traffic, 1697.It Cm AC_VO 1698(or 1699.Cm VO ) 1700voice traffic. 1701.El 1702.Pp 1703AC parameters are case-insensitive. 1704Traffic classification is done in the operating system using the 1705vlan priority associated with data frames or the 1706ToS (Type of Service) indication in IP-encapsulated frames. 1707If neither information is present, traffic is assigned to the 1708Best Effort (BE) category. 1709.Bl -tag -width indent 1710.It Cm ack Ar ac 1711Set the ACK policy for QoS transmissions by the local station; 1712this controls whether or not data frames transmitted by a station 1713require an ACK response from the receiving station. 1714To disable waiting for an ACK use 1715.Fl ack . 1716This parameter is applied only to the local station. 1717.It Cm acm Ar ac 1718Enable the Admission Control Mandatory (ACM) mechanism 1719for transmissions by the local station. 1720To disable the ACM use 1721.Fl acm . 1722On stations in a BSS this parameter is read-only and indicates 1723the setting received from the access point. 1724NB: ACM is not supported right now. 1725.It Cm aifs Ar ac Ar count 1726Set the Arbitration Inter Frame Spacing (AIFS) 1727channel access parameter to use for transmissions 1728by the local station. 1729On stations in a BSS this parameter is read-only and indicates 1730the setting received from the access point. 1731.It Cm cwmin Ar ac Ar count 1732Set the CWmin channel access parameter to use for transmissions 1733by the local station. 1734On stations in a BSS this parameter is read-only and indicates 1735the setting received from the access point. 1736.It Cm cwmax Ar ac Ar count 1737Set the CWmax channel access parameter to use for transmissions 1738by the local station. 1739On stations in a BSS this parameter is read-only and indicates 1740the setting received from the access point. 1741.It Cm txoplimit Ar ac Ar limit 1742Set the Transmission Opportunity Limit channel access parameter 1743to use for transmissions by the local station. 1744This parameter defines an interval of time when a WME station 1745has the right to initiate transmissions onto the wireless medium. 1746On stations in a BSS this parameter is read-only and indicates 1747the setting received from the access point. 1748.It Cm bss:aifs Ar ac Ar count 1749Set the AIFS channel access parameter to send to stations in a BSS. 1750This parameter is meaningful only when operating in ap mode. 1751.It Cm bss:cwmin Ar ac Ar count 1752Set the CWmin channel access parameter to send to stations in a BSS. 1753This parameter is meaningful only when operating in ap mode. 1754.It Cm bss:cwmax Ar ac Ar count 1755Set the CWmax channel access parameter to send to stations in a BSS. 1756This parameter is meaningful only when operating in ap mode. 1757.It Cm bss:txoplimit Ar ac Ar limit 1758Set the TxOpLimit channel access parameter to send to stations in a BSS. 1759This parameter is meaningful only when operating in ap mode. 1760.El 1761.It Cm wps 1762Enable Wireless Privacy Subscriber support. 1763Note that WPS support requires a WPS-capable supplicant. 1764To disable this function use 1765.Fl wps . 1766.El 1767.Pp 1768The following parameters support an optional access control list 1769feature available with some adapters when operating in ap mode; see 1770.Xr wlan_acl 4 . 1771This facility allows an access point to accept/deny association 1772requests based on the MAC address of the station. 1773Note that this feature does not significantly enhance security 1774as MAC address spoofing is easy to do. 1775.Bl -tag -width indent 1776.It Cm mac:add Ar address 1777Add the specified MAC address to the database. 1778Depending on the policy setting association requests from the 1779specified station will be allowed or denied. 1780.It Cm mac:allow 1781Set the ACL policy to permit association only by 1782stations registered in the database. 1783.It Cm mac:del Ar address 1784Delete the specified MAC address from the database. 1785.It Cm mac:deny 1786Set the ACL policy to deny association only by 1787stations registered in the database. 1788.It Cm mac:kick Ar address 1789Force the specified station to be deauthenticated. 1790This typically is done to block a station after updating the 1791address database. 1792.It Cm mac:open 1793Set the ACL policy to allow all stations to associate. 1794.It Cm mac:flush 1795Delete all entries in the database. 1796.It Cm mac:radius 1797Set the ACL policy to permit association only by 1798stations approved by a RADIUS server. 1799Note that this feature requires the 1800.Xr hostapd 8 1801program be configured to do the right thing 1802as it handles the RADIUS processing 1803(and marks stations as authorized). 1804.El 1805.Pp 1806The following parameters are related to a wireless interface operating in mesh 1807mode: 1808.Bl -tag -width indent 1809.It Cm meshid Ar meshid 1810Set the desired Mesh Identifier. 1811The Mesh ID is a string up to 32 characters in length. 1812A mesh interface must have a Mesh Identifier specified 1813to reach an operational state. 1814.It Cm meshttl Ar ttl 1815Set the desired ``time to live'' for mesh forwarded packets; 1816this is the number of hops a packet may be forwarded before 1817it is discarded. 1818The default setting for 1819.Cm meshttl 1820is 31. 1821.It Cm meshpeering 1822Enable or disable peering with neighbor mesh stations. 1823Stations must peer before any data packets can be exchanged. 1824By default 1825.Cm meshpeering 1826is enabled. 1827.It Cm meshforward 1828Enable or disable forwarding packets by a mesh interface. 1829By default 1830.Cm meshforward 1831is enabled. 1832.It Cm meshmetric Ar protocol 1833Set the specified 1834.Ar protocol 1835as the link metric protocol used on a mesh network. 1836The default protocol is called 1837.Ar AIRTIME . 1838The mesh interface will restart after changing this setting. 1839.It Cm meshpath Ar protocol 1840Set the specified 1841.Ar protocol 1842as the path selection protocol used on a mesh network. 1843The only available protocol at the moment is called 1844.Ar HWMP 1845(Hybrid Wireless Mesh Protocol). 1846The mesh interface will restart after changing this setting. 1847.It Cm hwmprootmode Ar mode 1848Stations on a mesh network can operate as ``root nodes.'' 1849Root nodes try to find paths to all mesh nodes and advertise themselves 1850regularly. 1851When there is a root mesh node on a network, other mesh nodes can setup 1852paths between themselves faster because they can use the root node 1853to find the destination. 1854This path may not be the best, but on-demand 1855routing will eventually find the best path. 1856The following modes are recognized: 1857.Pp 1858.Bl -tag -width ".Cm PROACTIVE" -compact 1859.It Cm DISABLED 1860Disable root mode. 1861.It Cm NORMAL 1862Send broadcast path requests every two seconds. 1863Nodes on the mesh without a path to this root mesh station with try to 1864discover a path to us. 1865.It Cm PROACTIVE 1866Send broadcast path requests every two seconds and every node must reply 1867with a path reply even if it already has a path to this root mesh station, 1868.It Cm RANN 1869Send broadcast root announcement (RANN) frames. 1870Nodes on the mesh without a path to this root mesh station with try to 1871discover a path to us. 1872.El 1873By default 1874.Cm hwmprootmode 1875is set to 1876.Ar DISABLED . 1877.It Cm hwmpmaxhops Ar cnt 1878Set the maximum number of hops allowed in an HMWP path to 1879.Ar cnt . 1880The default setting for 1881.Cm hwmpmaxhops 1882is 31. 1883.El 1884.Pp 1885The following parameters are for compatibility with other systems: 1886.Bl -tag -width indent 1887.It Cm nwid Ar ssid 1888Another name for the 1889.Cm ssid 1890parameter. 1891Included for 1892.Nx 1893compatibility. 1894.It Cm stationname Ar name 1895Set the name of this station. 1896The station name is not part of the IEEE 802.11 1897protocol though some interfaces support it. 1898As such it only 1899seems to be meaningful to identical or virtually identical equipment. 1900Setting the station name is identical in syntax to setting the SSID. 1901One can also use 1902.Cm station 1903for 1904.Bsx 1905compatibility. 1906.It Cm wep 1907Another way of saying 1908.Cm wepmode on . 1909Included for 1910.Bsx 1911compatibility. 1912.It Fl wep 1913Another way of saying 1914.Cm wepmode off . 1915Included for 1916.Bsx 1917compatibility. 1918.It Cm nwkey key 1919Another way of saying: 1920.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 1921Included for 1922.Nx 1923compatibility. 1924.It Cm nwkey Xo 1925.Sm off 1926.Ar n : k1 , k2 , k3 , k4 1927.Sm on 1928.Xc 1929Another way of saying 1930.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 1931Included for 1932.Nx 1933compatibility. 1934.It Fl nwkey 1935Another way of saying 1936.Cm wepmode off . 1937Included for 1938.Nx 1939compatibility. 1940.El 1941.Pp 1942The following parameters are specific to bridge interfaces: 1943.Bl -tag -width indent 1944.It Cm addm Ar interface 1945Add the interface named by 1946.Ar interface 1947as a member of the bridge. 1948The interface is put into promiscuous mode 1949so that it can receive every packet sent on the network. 1950.It Cm deletem Ar interface 1951Remove the interface named by 1952.Ar interface 1953from the bridge. 1954Promiscuous mode is disabled on the interface when 1955it is removed from the bridge. 1956.It Cm maxaddr Ar size 1957Set the size of the bridge address cache to 1958.Ar size . 1959The default is 100 entries. 1960.It Cm timeout Ar seconds 1961Set the timeout of address cache entries to 1962.Ar seconds 1963seconds. 1964If 1965.Ar seconds 1966is zero, then address cache entries will not be expired. 1967The default is 1200 seconds. 1968.It Cm addr 1969Display the addresses that have been learned by the bridge. 1970.It Cm static Ar interface-name Ar address 1971Add a static entry into the address cache pointing to 1972.Ar interface-name . 1973Static entries are never aged out of the cache or re-placed, even if the 1974address is seen on a different interface. 1975.It Cm deladdr Ar address 1976Delete 1977.Ar address 1978from the address cache. 1979.It Cm flush 1980Delete all dynamically-learned addresses from the address cache. 1981.It Cm flushall 1982Delete all addresses, including static addresses, from the address cache. 1983.It Cm discover Ar interface 1984Mark an interface as a 1985.Dq discovering 1986interface. 1987When the bridge has no address cache entry 1988(either dynamic or static) 1989for the destination address of a packet, 1990the bridge will forward the packet to all 1991member interfaces marked as 1992.Dq discovering . 1993This is the default for all interfaces added to a bridge. 1994.It Fl discover Ar interface 1995Clear the 1996.Dq discovering 1997attribute on a member interface. 1998For packets without the 1999.Dq discovering 2000attribute, the only packets forwarded on the interface are broadcast 2001or multicast packets and packets for which the destination address 2002is known to be on the interface's segment. 2003.It Cm learn Ar interface 2004Mark an interface as a 2005.Dq learning 2006interface. 2007When a packet arrives on such an interface, the source 2008address of the packet is entered into the address cache as being a 2009destination address on the interface's segment. 2010This is the default for all interfaces added to a bridge. 2011.It Fl learn Ar interface 2012Clear the 2013.Dq learning 2014attribute on a member interface. 2015.It Cm span Ar interface 2016Add the interface named by 2017.Ar interface 2018as a span port on the bridge. 2019Span ports transmit a copy of every frame received by the bridge. 2020This is most useful for snooping a bridged network passively on 2021another host connected to one of the span ports of the bridge. 2022.It Fl span Ar interface 2023Delete the interface named by 2024.Ar interface 2025from the list of span ports of the bridge. 2026.It Cm stp Ar interface 2027Enable Spanning Tree protocol on 2028.Ar interface . 2029The 2030.Xr bridge 4 2031driver has support for the IEEE 802.1D Spanning Tree protocol (STP). 2032Spanning Tree is used to detect and remove loops in a network topology. 2033.It Fl stp Ar interface 2034Disable Spanning Tree protocol on 2035.Ar interface . 2036This is the default for all interfaces added to a bridge. 2037.It Cm maxage Ar seconds 2038Set the time that a Spanning Tree protocol configuration is valid. 2039The default is 20 seconds. 2040The minimum is 1 second and the maximum is 255 seconds. 2041.It Cm fwddelay Ar seconds 2042Set the time that must pass before an interface begins forwarding 2043packets when Spanning Tree is enabled. 2044The default is 15 seconds. 2045The minimum is 1 second and the maximum is 255 seconds. 2046.It Cm hellotime Ar seconds 2047Set the time between broadcasting of Spanning Tree protocol 2048configuration messages. 2049The default is 2 seconds. 2050The minimum is 1 second and the maximum is 255 seconds. 2051.It Cm priority Ar value 2052Set the bridge priority for Spanning Tree. 2053The default is 32768. 2054The minimum is 0 and the maximum is 65536. 2055.It Cm ifpriority Ar interface Ar value 2056Set the Spanning Tree priority of 2057.Ar interface 2058to 2059.Ar value . 2060The default is 128. 2061The minimum is 0 and the maximum is 255. 2062.Pp 2063The priority is used to select which interface out of all 2064forwarding and bonded interfaces with the same MAC 2065to output a packet on whe 2066.Cm link2 2067mode is not being used. 2068Note that interfaces in the 'blocking' state do not participate 2069in the priority selection. 2070If the priorities are the same on a non-bonded member, the 2071designated member will be used. 2072.It Cm ifpathcost Ar interface Ar value 2073Set the Spanning Tree path cost of 2074.Ar interface 2075to 2076.Ar value . 2077The default is 55. 2078The minimum is 0 and the maximum is 65535. 2079.Pp 2080The path cost is added to both incoming and outgoing packets on the 2081member, lower values will make the member more valuable. 2082.It Cm ifbondweight Ar interface Ar value 2083Set the number of packets to output on a bonded member before 2084round-robining to the next member. 2085The default is 1. 2086Larger values or different values for each member can be used 2087if bursting would be beneficial or if the outgoing bandwidth 2088on each of the members is asymmetric. 2089For example, one specify a value of 6 on tap0 and 4 on tap1 2090for a 6:4 ratio. 2091Remember that this also controls packet bursting. 2092.It Cm link0 2093The link0 option enables transparent bridging mode. 2094The bridge will make every effort to retain the ethernet header 2095when forwarding packets between interfaces, making the bridging 2096function work more like a hardware bridge device. 2097.It Cm link1 2098The link1 option enables keepalive transmission and automatically 2099places a member into a special blocked mode if no keepalive reception 2100occurs. 2101If either sides of the link uses this option then both sides must use 2102this option. 2103This option is impemented by sending CFG updates on the hello interval 2104to the remote. 2105The link is considered lost after 10 intervals (typically 20 seconds). 2106.It Cm link2 2107The link2 option enables channel bonding (see also ifbondweight). 2108All member interfaces with the same mac address are considered to 2109be in a bonding group. 2110When something like 2111.Xr tap 4 2112is used, you can manually control or copy the mac to create bonding groups. 2113When interface bonding is enabled normally blocked interfaces belonging 2114to the same bonding group as an active forwarding interface will be 2115changed to the bonding state. 2116Both sides of link the member represents must operate in bonding mode 2117for this to work, otherwise the remote end may decide to throw away 2118half your packets. 2119.El 2120.Pp 2121The following parameters are specific to IP tunnel interfaces, 2122.Xr gif 4 : 2123.Bl -tag -width indent 2124.It Cm tunnel Ar src_addr dest_addr 2125Configure the physical source and destination address for IP tunnel 2126interfaces. 2127The arguments 2128.Ar src_addr 2129and 2130.Ar dest_addr 2131are interpreted as the outer source/destination for the encapsulating 2132IPv4/IPv6 header. 2133.It Fl tunnel 2134Unconfigure the physical source and destination address for IP tunnel 2135interfaces previously configured with 2136.Cm tunnel . 2137.It Cm deletetunnel 2138Another name for the 2139.Fl tunnel 2140parameter. 2141.El 2142.Pp 2143The following parameters are specific to 2144.Xr vlan 4 2145interfaces: 2146.Bl -tag -width indent 2147.It Cm vlan Ar vlan_tag 2148Set the VLAN tag value to 2149.Ar vlan_tag . 2150This value is a 16-bit number which is used to create an 802.1Q 2151VLAN header for packets sent from the 2152.Xr vlan 4 2153interface. 2154Note that 2155.Cm vlan 2156and 2157.Cm vlandev 2158must both be set at the same time. 2159.It Cm vlandev Ar iface 2160Associate the physical interface 2161.Ar iface 2162with a 2163.Xr vlan 4 2164interface. 2165Packets transmitted through the 2166.Xr vlan 4 2167interface will be 2168diverted to the specified physical interface 2169.Ar iface 2170with 802.1Q VLAN encapsulation. 2171Packets with 802.1Q encapsulation received 2172by the parent interface with the correct VLAN tag will be diverted to 2173the associated 2174.Xr vlan 4 2175pseudo-interface. 2176The 2177.Xr vlan 4 2178interface is assigned a 2179copy of the parent interface's flags and the parent's ethernet address. 2180The 2181.Cm vlandev 2182and 2183.Cm vlan 2184must both be set at the same time. 2185If the 2186.Xr vlan 4 2187interface already has 2188a physical interface associated with it, this command will fail. 2189To 2190change the association to another physical interface, the existing 2191association must be cleared first. 2192.Pp 2193Note: if the hardware tagging capability 2194is set on the parent interface, the 2195.Xr vlan 4 2196pseudo 2197interface's behavior changes: 2198the 2199.Xr vlan 4 2200interface recognizes that the 2201parent interface supports insertion and extraction of VLAN tags on its 2202own (usually in firmware) and that it should pass packets to and from 2203the parent unaltered. 2204.It Fl vlandev Op Ar iface 2205If the driver is a 2206.Xr vlan 4 2207pseudo device, disassociate the parent interface from it. 2208This breaks the link between the 2209.Xr vlan 4 2210interface and its parent, 2211clears its VLAN tag, flags and its link address and shuts the interface down. 2212The 2213.Ar iface 2214argument is useless and hence deprecated. 2215.El 2216.Pp 2217The following parameters are specific to 2218.Xr carp 4 2219interfaces: 2220.Bl -tag -width indent 2221.It Cm advbase Ar seconds 2222Specifies the base of the advertisement interval in seconds. 2223The acceptable values are 1 to 255. 2224The default value is 1. 2225.\" The default value is 2226.\" .Dv CARP_DFLTINTV . 2227.It Cm advskew Ar interval 2228Specifies the skew to add to the base advertisement interval to 2229make one host advertise slower than another host. 2230It is specified in 1/256 of seconds. 2231The acceptable values are 1 to 254. 2232The default value is 0. 2233.It Cm pass Ar phrase 2234Set the authentication key to 2235.Ar phrase . 2236.It Cm vhid Ar n 2237Set the virtual host ID. 2238This is a required setting. 2239Acceptable values are 1 to 255. 2240.El 2241.Pp 2242The 2243.Nm 2244utility displays the current configuration for a network interface 2245when no optional parameters are supplied. 2246If a protocol family is specified, 2247.Nm 2248will report only the details specific to that protocol family. 2249.Pp 2250If the 2251.Fl m 2252flag is passed before an interface name, 2253.Nm 2254will display the capability list and all 2255of the supported media for the specified interface. 2256If 2257.Fl L 2258flag is supplied, address lifetime is displayed for IPv6 addresses, 2259as time offset string. 2260.Pp 2261Optionally, the 2262.Fl a 2263flag may be used instead of an interface name. 2264This flag instructs 2265.Nm 2266to display information about all interfaces in the system. 2267The 2268.Fl d 2269flag limits this to interfaces that are down, and 2270.Fl u 2271limits this to interfaces that are up. 2272When no arguments are given, 2273.Fl a 2274is implied. 2275.Pp 2276The 2277.Fl l 2278flag may be used to list all available interfaces on the system, with 2279no other additional information. 2280Use of this flag is mutually exclusive 2281with all other flags and commands, except for 2282.Fl d 2283(only list interfaces that are down) 2284and 2285.Fl u 2286(only list interfaces that are up). 2287.Pp 2288The 2289.Fl v 2290flag may be used to get more verbose status for an interface. 2291.Pp 2292The 2293.Fl C 2294flag may be used to list all of the interface cloners available on 2295the system, with no additional information. 2296Use of this flag is mutually exclusive with all other flags and commands. 2297.Pp 2298The 2299.Fl k 2300flag causes keying information for the interface, if available, to be 2301printed. 2302For example, the values of 802.11 WEP keys will be printed, if accessible to 2303the current user. 2304This information is not printed by default, as it may be considered 2305sensitive. 2306.Pp 2307Only the super-user may modify the configuration of a network interface. 2308.Sh DIAGNOSTICS 2309Messages indicating the specified interface does not exist, the 2310requested address is unknown, or the user is not privileged and 2311tried to alter an interface's configuration. 2312.Sh SEE ALSO 2313.Xr netstat 1 , 2314.Xr carp 4 , 2315.Xr ifmedia 4 , 2316.Xr netintro 4 , 2317.Xr polling 4 , 2318.Xr vlan 4 , 2319.\" .Xr eon 5 , 2320.Xr rc 8 , 2321.Xr routed 8 , 2322.Xr sysctl 8 2323.Sh HISTORY 2324The 2325.Nm 2326utility appeared in 2327.Bx 4.2 . 2328.Sh BUGS 2329Basic IPv6 node operation requires a link-local address on each 2330interface configured for IPv6. 2331Normally, such an address is automatically configured by the 2332kernel on each interface added to the system; this behaviour may 2333be disabled by setting the sysctl MIB variable 2334.Va net.inet6.ip6.auto_linklocal 2335to 0. 2336.Pp 2337If you delete such an address using 2338.Nm , 2339the kernel may act very odd. 2340Do this at your own risk. 2341