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.\" 3. 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 November 12, 2012 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 359Deprecated, use polling or npolling instead. 360.It Cm polling , npolling 361Turn on 362.Xr polling 4 363feature and disable interrupts on the interface, if the driver supports 364this mode. 365.It Fl polling , npolling 366Turn off 367.Xr polling 4 368feature and enable interrupt mode on the interface. 369.It Cm create 370Create the specified network pseudo-device. 371If the interface is given without a unit number, try to create a new 372device with an arbitrary unit number. 373If creation of an arbitrary device is successful, the new device name is 374printed to standard output unless the interface is renamed or destroyed 375in the same 376.Nm 377invocation. 378.It Cm destroy 379Destroy the specified network pseudo-device. 380.It Cm plumb 381Another name for the 382.Cm create 383parameter. 384Included for 385.Tn Solaris 386compatibility. 387.It Cm unplumb 388Another name for the 389.Cm destroy 390parameter. 391Included for 392.Tn Solaris 393compatibility. 394.It Cm metric Ar n 395Set the routing metric of the interface to 396.Ar n , 397default 0. 398The routing metric is used by the routing protocol 399.Pq Xr routed 8 . 400Higher metrics have the effect of making a route 401less favorable; metrics are counted as additional hops 402to the destination network or host. 403.It Cm mtu Ar n 404Set the maximum transmission unit of the interface to 405.Ar n , 406default is interface specific. 407The MTU is used to limit the size of packets that are transmitted on an 408interface. 409Not all interfaces support setting the MTU, and some interfaces have 410range restrictions. 411.It Cm tsolen Ar n 412Set the maximum amount of data 413that TCP segmentation offloading is allowed to aggregate to 414.Ar n , 415the default value is interface specific. 416This setting only takes effect on interfaces 417that support TCP segmentation offloading. 418.It Cm netmask Ar mask 419.\" (Inet and ISO.) 420(Inet only.) 421Specify how much of the address to reserve for subdividing 422networks into sub-networks. 423The mask includes the network part of the local address 424and the subnet part, which is taken from the host field of the address. 425The mask can be specified as a single hexadecimal number 426with a leading 427.Ql 0x , 428with a dot-notation Internet address, 429or with a pseudo-network name listed in the network table 430.Xr networks 5 . 431The mask contains 1's for the bit positions in the 32-bit address 432which are to be used for the network and subnet parts, 433and 0's for the host part. 434The mask should contain at least the standard network portion, 435and the subnet field should be contiguous with the network 436portion. 437.Pp 438The netmask can also be specified in CIDR notation after the address. 439See the 440.Ar address 441option above for more information. 442.It Cm autoconf 443(Inet6 only.) 444Enable autoconfiguration. 445.It Fl autoconf 446Disable autoconfiguration. 447.It Cm pltime Ar n 448(Inet6 only.) 449Set preferred lifetime for the address. 450.It Cm vltime Ar n 451(Inet6 only.) 452Set valid lifetime for the address. 453.It Cm prefixlen Ar len 454(Inet6 only.) 455Specify that 456.Ar len 457bits are reserved for subdividing networks into sub-networks. 458The 459.Ar len 460must be integer, and for syntactical reason it must be between 0 to 128. 461It is almost always 64 under the current IPv6 assignment rule. 462If the parameter is omitted, 64 is used. 463.Pp 464The prefix can also be specified using the slash notation after the address. 465See the 466.Ar address 467option above for more information. 468.It Cm deprecated 469(Inet6 only.) 470Set the IPv6 deprecated address bit. 471.It Fl deprecated 472(Inet6 only.) 473Clear the IPv6 deprecated address bit. 474.It Cm tentative 475(Inet6 only.) 476Set the IPv6 tentative address bit. 477.It Fl tentative 478(Inet6 only.) 479Clear the IPv6 tentative address bit. 480.\" see 481.\" Xr eon 5 . 482.\" .It Cm nsellength Ar n 483.\" .Pf ( Tn ISO 484.\" only) 485.\" This specifies a trailing number of bytes for a received 486.\" .Tn NSAP 487.\" used for local identification, the remaining leading part of which is 488.\" taken to be the 489.\" .Tn NET 490.\" (Network Entity Title). 491.\" The default value is 1, which is conformant to US 492.\" .Tn GOSIP . 493.\" When an ISO address is set in an ifconfig command, 494.\" it is really the 495.\" .Tn NSAP 496.\" which is being specified. 497.\" For example, in 498.\" .Tn US GOSIP , 499.\" 20 hex digits should be 500.\" specified in the 501.\" .Tn ISO NSAP 502.\" to be assigned to the interface. 503.\" There is some evidence that a number different from 1 may be useful 504.\" for 505.\" .Tn AFI 506.\" 37 type addresses. 507.It Cm range Ar netrange 508Under appletalk, set the interface to respond to a 509.Ar netrange 510of the form 511.Ar startnet Ns - Ns Ar endnet . 512Appletalk uses this scheme instead of 513netmasks though 514.Dx 515implements it internally as a set of netmasks. 516.It Cm remove 517Another name for the 518.Fl alias 519parameter. 520Introduced for compatibility 521with 522.Bsx . 523.It Cm phase 524The argument following this specifies the version (phase) of the 525Appletalk network attached to the interface. 526Values of 1 or 2 are permitted. 527.Sm off 528.It Cm link Op Cm 0 No - Cm 2 529.Sm on 530Enable special processing of the link level of the interface. 531These three options are interface specific in actual effect, however, 532they are in general used to select special modes of operation. 533An example 534of this is to enable SLIP compression, or to select the connector type 535for some Ethernet cards. 536Refer to the man page for the specific driver 537for more information. 538.Sm off 539.It Fl link Op Cm 0 No - Cm 2 540.Sm on 541Disable special processing at the link level with the specified interface. 542.It Cm compress 543Another name for the 544.Cm link0 545parameter. 546.It Cm normal 547Another name for the 548.Fl link0 549parameter. 550.It Cm noicmp 551Another name for the 552.Cm link1 553parameter. 554.It Cm monitor 555Put the interface in monitor mode. 556No packets are transmitted, and received packets are discarded after 557.Xr bpf 4 558processing. 559.It Fl monitor 560Take the interface out of monitor mode. 561.It Cm up 562Mark an interface 563.Dq up . 564This may be used to enable an interface after an 565.Dq Nm Cm down . 566It happens automatically when setting the first address on an interface. 567If the interface was reset when previously marked down, 568the hardware will be re-initialized. 569.El 570.Pp 571The following parameters are specific to cloning 572IEEE 802.11 wireless interfaces with the 573.Cm create 574request: 575.Bl -tag -width indent 576.It Cm wlandev Ar device 577Use 578.Ar device 579as the parent for the cloned device. 580.It Cm wlanmode Ar mode 581Specify the operating mode for this cloned device. 582.Ar mode 583is one of 584.Cm sta , 585.Cm ahdemo 586(or 587.Cm adhoc-demo ), 588.Cm ibss , 589(or 590.Cm adhoc ), 591.Cm ap , 592(or 593.Cm hostap ), 594.Cm wds , 595.Cm tdma , 596.Cm mesh , 597and 598.Cm monitor . 599The operating mode of a cloned interface cannot be changed. 600The 601.Cm tdma 602mode is actually implemented as an 603.Cm adhoc-demo 604interface with special properties. 605.It Cm wlanbssid Ar bssid 606The 802.11 mac address to use for the bssid. 607This must be specified at create time for a legacy 608.Cm wds 609device. 610.It Cm wlanaddr Ar address 611The local mac address. 612If this is not specified then a mac address will automatically be assigned 613to the cloned device. 614Typically this address is the same as the address of the parent device 615but if the 616.Cm bssid 617parameter is specified then the driver will craft a unique address for 618the device (if supported). 619.It Cm wdslegacy 620Mark a 621.Cm wds 622device as operating in ``legacy mode''. 623Legacy 624.Cm wds 625devices have a fixed peer relationship and do not, for example, roam 626if their peer stops communicating. 627For completeness a Dynamic WDS (DWDS) interface may marked as 628.Fl wdslegacy . 629.It Cm bssid 630Request a unique local mac address for the cloned device. 631This is only possible if the device supports multiple mac addresses. 632To force use of the parent's mac address use 633.Fl bssid . 634.It Cm beacons 635Mark the cloned interface as depending on hardware support to 636track received beacons. 637To have beacons tracked in software use 638.Fl beacons . 639For 640.Cm hostap 641mode 642.Fl beacons 643can also be used to indicate no beacons should 644be transmitted; this can be useful when creating a WDS configuration but 645.Cm wds 646interfaces can only be created as companions to an access point. 647.El 648.Pp 649The following parameters are specific to IEEE 802.11 wireless interfaces 650cloned with a 651.Cm create 652operation: 653.Bl -tag -width indent 654.It Cm ampdu 655Enable sending and receiving AMPDU frames when using 802.11n (default). 656The 802.11n specification states a compliant station must be capable 657of receiving AMPDU frames but transmission is optional. 658Use 659.Fl ampdu 660to disable all use of AMPDU with 802.11n. 661For testing and/or to work around interoperability problems one can use 662.Cm ampdutx 663and 664.Cm ampdurx 665to control use of AMPDU in one direction. 666.It Cm ampdudensity Ar density 667Set the AMPDU density parameter used when operating with 802.11n. 668This parameter controls the inter-packet gap for AMPDU frames. 669The sending device normally controls this setting but a receiving station 670may request wider gaps. 671Legal values for 672.Ar density 673are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds). 674A value of 675.Cm - 676is treated the same as 0. 677.It Cm ampdulimit Ar limit 678Set the limit on packet size for receiving AMPDU frames when operating 679with 802.11n. 680Legal values for 681.Ar limit 682are 8192, 16384, 32768, and 65536 but one can also specify 683just the unique prefix: 8, 16, 32, 64. 684Note the sender may limit the size of AMPDU frames to be less 685than the maximum specified by the receiving station. 686.It Cm amsdu 687Enable sending and receiving AMSDU frames when using 802.11n. 688By default AMSDU is received but not transmitted. 689Use 690.Fl amsdu 691to disable all use of AMSDU with 802.11n. 692For testing and/or to work around interoperability problems one can use 693.Cm amsdutx 694and 695.Cm amsdurx 696to control use of AMSDU in one direction. 697.It Cm amsdulimit Ar limit 698Set the limit on packet size for sending and receiving AMSDU frames 699when operating with 802.11n. 700Legal values for 701.Ar limit 702are 7935 and 3839 (bytes). 703Note the sender may limit the size of AMSDU frames to be less 704than the maximum specified by the receiving station. 705Note also that devices are not required to support the 7935 limit, 706only 3839 is required by the specification and the larger value 707may require more memory to be dedicated to support functionality 708that is rarely used. 709.It Cm apbridge 710When operating as an access point, pass packets between 711wireless clients directly (default). 712To instead let them pass up through the 713system and be forwarded using some other mechanism, use 714.Fl apbridge . 715Disabling the internal bridging 716is useful when traffic is to be processed with 717packet filtering. 718.It Cm authmode Ar mode 719Set the desired authentication mode in infrastructure mode. 720Not all adapters support all modes. 721The set of 722valid modes is 723.Cm none , open , shared 724(shared key), 725.Cm 8021x 726(IEEE 802.1x), 727and 728.Cm wpa 729(IEEE WPA/WPA2/802.11i). 730The 731.Cm 8021x 732and 733.Cm wpa 734modes are only useful when using an authentication service 735(a supplicant for client operation or an authenticator when 736operating as an access point). 737Modes are case insensitive. 738.It Cm bgscan 739Enable background scanning when operating as a station. 740Background scanning is a technique whereby a station associated to 741an access point will temporarily leave the channel to scan for 742neighboring stations. 743This allows a station to maintain a cache of nearby access points 744so that roaming between access points can be done without 745a lengthy scan operation. 746Background scanning is done only when a station is not busy and 747any outbound traffic will cancel a scan operation. 748Background scanning should never cause packets to be lost though 749there may be some small latency if outbound traffic interrupts a 750scan operation. 751By default background scanning is enabled if the device is capable. 752To disable background scanning, use 753.Fl bgscan . 754Background scanning is controlled by the 755.Cm bgscanidle 756and 757.Cm bgscanintvl 758parameters. 759Background scanning must be enabled for roaming; this is an artifact 760of the current implementation and may not be required in the future. 761.It Cm bgscanidle Ar idletime 762Set the minimum time a station must be idle (not transmitting or 763receiving frames) before a background scan is initiated. 764The 765.Ar idletime 766parameter is specified in milliseconds. 767By default a station must be idle at least 250 milliseconds before 768a background scan is initiated. 769The idle time may not be set to less than 100 milliseconds. 770.It Cm bgscanintvl Ar interval 771Set the interval at which background scanning is attempted. 772The 773.Ar interval 774parameter is specified in seconds. 775By default a background scan is considered every 300 seconds (5 minutes). 776The 777.Ar interval 778may not be set to less than 15 seconds. 779.It Cm bintval Ar interval 780Set the interval at which beacon frames are sent when operating in 781ad-hoc or ap mode. 782The 783.Ar interval 784parameter is specified in TU's (1024 usecs). 785By default beacon frames are transmitted every 100 TU's. 786.It Cm bmissthreshold Ar count 787Set the number of consecutive missed beacons at which the station 788will attempt to roam (i.e., search for a new access point). 789The 790.Ar count 791parameter must be in the range 1 to 255; though the 792upper bound may be reduced according to device capabilities. 793The default threshold is 7 consecutive missed beacons; but 794this may be overridden by the device driver. 795Another name for the 796.Cm bmissthreshold 797parameter is 798.Cm bmiss . 799.It Cm bssid Ar address 800Specify the MAC address of the access point to use when operating 801as a station in a BSS network. 802This overrides any automatic selection done by the system. 803To disable a previously selected access point, supply 804.Cm any , none , 805or 806.Cm - 807for the address. 808This option is useful when more than one access point uses the same SSID. 809Another name for the 810.Cm bssid 811parameter is 812.Cm ap . 813.It Cm burst 814Enable packet bursting. 815Packet bursting is a transmission technique whereby the wireless 816medium is acquired once to send multiple frames and the interframe 817spacing is reduced. 818This technique can significantly increase throughput by reducing 819transmission overhead. 820Packet bursting is supported by the 802.11e QoS specification 821and some devices that do not support QoS may still be capable. 822By default packet bursting is enabled if a device is capable 823of doing it. 824To disable packet bursting, use 825.Fl burst . 826.It Cm chanlist Ar channels 827Set the desired channels to use when scanning for access 828points, neighbors in an IBSS network, or looking for unoccupied 829channels when operating as an access point. 830The set of channels is specified as a comma-separated list with 831each element in the list representing either a single channel number or a range 832of the form 833.Dq Li a-b . 834Channel numbers must be in the range 1 to 255 and be permissible 835according to the operating characteristics of the device. 836.It Cm channel Ar number 837Set a single desired channel. 838Channels range from 1 to 255, but the exact selection available 839depends on the region your adaptor was manufactured for. 840Setting 841the channel to 842.Li any , 843or 844.Cm - 845will clear any desired channel and, if the device is marked up, 846force a scan for a channel to operate on. 847Alternatively the frequency, in megahertz, may be specified 848instead of the channel number. 849.Pp 850When there are several ways to use a channel the channel 851number/frequency may be appended with attributes to clarify. 852For example, if a device is capable of operating on channel 6 853with 802.11n and 802.11g then one can specify that g-only use 854should be used by specifying ``6:g''. 855Similarly the channel width can be specified by appending it 856with ``/''; e.g. ``6/40'' specifies a 40MHz wide channel, 857These attributes can be combined as in: ``6:ht/40''. 858The full set of flags specified following a `:'' are: 859.Cm a 860(802.11a), 861.Cm b 862(802.11b), 863.Cm d 864(Atheros Dynamic Turbo mode), 865.Cm g 866(802.11g), 867.Cm h 868or 869.Cm n 870(802.11n aka HT), 871.Cm s 872(Atheros Static Turbo mode), 873and 874.Cm t 875(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt''). 876The full set of channel widths following a '/' are: 877.Cm 5 878(5MHz aka quarter-rate channel), 879.Cm 10 880(10MHz aka half-rate channel), 881.Cm 20 882(20MHz mostly for use in specifying ht20), 883and 884.Cm 40 885(40MHz mostly for use in specifying ht40), 886In addition, 887a 40MHz HT channel specification may include the location 888of the extension channel by appending ``+'' or ``-'' for above and below, 889respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation 890with the center channel at frequency 2437 and the extension channel above. 891.It Cm country Ar name 892Set the country code to use in calculating the regulatory constraints 893for operation. 894In particular the set of available channels, how the wireless device 895will operation on the channels, and the maximum transmit power that 896can be used on a channel are defined by this setting. 897Country/Region codes are specified as a 2-character abbreviation 898defined by ISO 3166 or using a longer, but possibly ambiguous, spelling; 899e.g. "ES" and "Spain". 900The set of country codes are taken from /etc/regdomain.xml and can also 901be viewed with the ``list countries'' request. 902Note that not all devices support changing the country code from a default 903setting; typically stored in EEPROM. 904See also 905.Cm regdomain , 906.Cm indoor , 907.Cm outdoor , 908and 909.Cm anywhere . 910.It Cm dfs 911Enable Dynamic Frequency Selection (DFS) as specified in 802.11h. 912DFS embodies several facilities including detection of overlapping 913radar signals, dynamic transmit power control, and channel selection 914according to a least-congested criteria. 915DFS support is mandatory for some 5Ghz frequencies in certain 916locales (e.g. ETSI). 917By default DFS is enabled according to the regulatory definitions 918specified in /etc/regdomain.xml and the curent country code, regdomain, 919and channel. 920Note the underlying device (and driver) must support radar detection 921for full DFS support to work. 922To be fully compliant with the local regulatory agency frequencies that 923require DFS should not be used unless it is fully supported. 924Use 925.Fl dfs 926to disable this functionality for testing. 927.It Cm dotd 928Enable support for the 802.11d specification (default). 929When this support is enabled in station mode, beacon frames that advertise 930a country code different than the currently configured country code will 931cause an event to be dispatched to user applications. 932This event can be used by the station to adopt that country code and 933operate according to the associated regulatory constraints. 934When operating as an access point with 802.11d enabled the beacon and 935probe response frames transmitted will advertise the current regulatory 936domain settings. 937To disable 802.11d use 938.Fl dotd . 939.It Cm doth 940Enable 802.11h support including spectrum management. 941When 802.11h is enabled beacon and probe response frames will have 942the SpectrumMgt bit set in the capabilities field and 943country and power constraint information elements will be present. 944802.11h support also includes handling Channel Switch Announcements (CSA) 945which are a mechanism to coordinate channel changes by an access point. 946By default 802.11h is enabled if the device is capable. 947To disable 802.11h use 948.Fl doth . 949.It Cm deftxkey Ar index 950Set the default key to use for transmission. 951Typically this is only set when using WEP encryption. 952Note that you must set a default transmit key 953for the system to know which key to use in encrypting outbound traffic. 954The 955.Cm weptxkey 956is an alias for this request; it is provided for backwards compatibility. 957.It Cm dtimperiod Ar period 958Set the 959DTIM 960period for transmitting buffered multicast data frames when 961operating in ap mode. 962The 963.Ar period 964specifies the number of beacon intervals between DTIM 965and must be in the range 1 to 15. 966By default DTIM is 1 (i.e., DTIM occurs at each beacon). 967.It Cm dturbo 968Enable the use of Atheros Dynamic Turbo mode when communicating with 969another Dynamic Turbo-capable station. 970Dynamic Turbo mode is an Atheros-specific mechanism by which 971stations switch between normal 802.11 operation and a ``boosted'' 972mode in which a 40MHz wide channel is used for communication. 973Stations using Dynamic Turbo mode operate boosted only when the 974channel is free of non-dturbo stations; when a non-dturbo station 975is identified on the channel all stations will automatically drop 976back to normal operation. 977By default, Dynamic Turbo mode is not enabled, even if the device is capable. 978Note that turbo mode (dynamic or static) is only allowed on some 979channels depending on the regulatory constraints; use the 980.Cm list chan 981command to identify the channels where turbo mode may be used. 982To disable Dynamic Turbo mode use 983.Fl dturbo . 984.It Cm dwds 985Enable Dynamic WDS (DWDS) support. 986DWDS is a facility by which 4-address traffic can be carried between 987stations operating in infrastructure mode. 988A station first associates to an access point and authenticates using 989normal procedures (e.g. WPA). 990Then 4-address frames are passed to carry traffic for stations 991operating on either side of the wireless link. 992DWDS extends the normal WDS mechanism by leveraging existing security 993protocols and eliminating static binding. 994.Pp 995When DWDS is enabled on an access point 4-address frames received from 996an authorized station will generate a ``DWDS discovery'' event to user 997applications. 998This event should be used to create a WDS interface that is bound 999to the remote station (and usually plumbed into a bridge). 1000Once the WDS interface is up and running 4-address traffic then logically 1001flows through that interface. 1002.Pp 1003When DWDS is enabled on a station, traffic with a destination address 1004different from the peer station are encapsulated in a 4-address frame 1005and transmitted to the peer. 1006All 4-address traffic uses the security information of the stations 1007(e.g. cryptographic keys). 1008A station is associated using 802.11n facilities may transport 10094-address traffic using these same mechanisms; this depends on available 1010resources and capabilities of the device. 1011The DWDS implementation guards against layer 2 routing loops of 1012multicast traffic. 1013.It Cm ff 1014Enable the use of Atheros Fast Frames when communicating with 1015another Fast Frames-capable station. 1016Fast Frames are an encapsulation technique by which two 802.3 1017frames are transmitted in a single 802.11 frame. 1018This can noticeably improve throughput but requires that the 1019receiving station understand how to decapsulate the frame. 1020Fast frame use is negotiated using the Atheros 802.11 vendor-specific 1021protocol extension so enabling use is safe when communicating with 1022non-Atheros devices. 1023By default, use of fast frames is enabled if the device is capable. 1024To explicitly disable fast frames, use 1025.Fl ff . 1026.It Cm fragthreshold Ar length 1027Set the threshold for which transmitted frames are broken into fragments. 1028The 1029.Ar length 1030argument is the frame size in bytes and must be in the range 256 to 2346. 1031Setting 1032.Ar length 1033to 1034.Li 2346 , 1035.Cm any , 1036or 1037.Cm - 1038disables transmit fragmentation. 1039Not all adapters honor the fragmentation threshold. 1040.It Cm hidessid 1041When operating as an access point, do not broadcast the SSID 1042in beacon frames or respond to probe request frames unless 1043they are directed to the ap (i.e., they include the ap's SSID). 1044By default, the SSID is included in beacon frames and 1045undirected probe request frames are answered. 1046To re-enable the broadcast of the SSID etc., use 1047.Fl hidessid . 1048.It Cm ht 1049Enable use of High Throughput (HT) when using 802.11n (default). 1050The 802.11n specification includes mechanisms for operation 1051on 20MHz and 40MHz wide channels using different signalling mechanisms 1052than specified in 802.11b, 802.11g, and 802.11a. 1053Stations negotiate use of these facilities, termed HT20 and HT40, 1054when they associate. 1055To disable all use of 802.11n use 1056.Fl ht . 1057To disable use of HT20 (e.g. to force only HT40 use) use 1058.Fl ht20 . 1059To disable use of HT40 use 1060.Fl ht40 . 1061.Pp 1062HT configuration is used to ``auto promote'' operation 1063when several choices are available. 1064For example, if a station associates to an 11n-capable access point 1065it controls whether the station uses legacy operation, HT20, or HT40. 1066When an 11n-capable device is setup as an access point and 1067Auto Channel Selection is used to locate a channel to operate on, 1068HT configuration controls whether legacy, HT20, or HT40 operation is setup 1069on the selected channel. 1070If a fixed channel is specified for a station then HT configuration can 1071be given as part of the channel specification; e.g. 6:ht/20 to setup 1072HT20 operation on channel 6. 1073.It Cm htcompat 1074Enable use of compatibility support for pre-802.11n devices (default). 1075The 802.11n protocol specification went through several incompatible iterations. 1076Some vendors implemented 11n support to older specifications that 1077will not interoperate with a purely 11n-compliant station. 1078In particular the information elements included in management frames 1079for old devices are different. 1080When compatibility support is enabled both standard and compatible data 1081will be provided. 1082Stations that associate using the compatibility mechanisms are flagged 1083in ``list sta''. 1084To disable compatibility support use 1085.Fl htcompat . 1086.It Cm htprotmode Ar technique 1087For interfaces operating in 802.11n, use the specified 1088.Ar technique 1089for protecting HT frames in a mixed legacy/HT network. 1090The set of valid techniques is 1091.Cm off , 1092and 1093.Cm rts 1094(RTS/CTS, default). 1095Technique names are case insensitive. 1096.It Cm inact 1097Enable inactivity processing for stations associated to an 1098access point (default). 1099When operating as an access point the 802.11 layer monitors 1100the activity of each associated station. 1101When a station is inactive for 5 minutes it will send several 1102``probe frames'' to see if the station is still present. 1103If no response is received then the station is deauthenticated. 1104Applications that prefer to handle this work can disable this 1105facility by using 1106.Fl inact . 1107.It Cm indoor 1108Set the location to use in calculating regulatory constraints. 1109The location is also advertised in beacon and probe response frames 1110when 802.11d is enabled with 1111.Cm dotd . 1112See also 1113.Cm outdoor , 1114.Cm anywhere , 1115.Cm country , 1116and 1117.Cm regdomain . 1118.It Cm list active 1119Display the list of channels available for use taking into account 1120any restrictions set with the 1121.Cm chanlist 1122directive. 1123See the description of 1124.Cm list chan 1125for more information. 1126.It Cm list caps 1127Display the adaptor's capabilities, including the operating 1128modes supported. 1129.It Cm list chan 1130Display the list of channels available for use. 1131Channels are shown with their IEEE channel number, equivalent 1132frequency, and usage modes. 1133Channels identified as 1134.Ql 11g 1135are also usable in 1136.Ql 11b 1137mode. 1138Channels identified as 1139.Ql 11a Turbo 1140may be used only for Atheros' Static Turbo mode 1141(specified with 1142.Cm mediaopt turbo ) . 1143Channels marked with a 1144.Ql * 1145have a regulatory constraint that they be passively scanned. 1146This means a station is not permitted to transmit on the channel until 1147it identifies the channel is being used for 802.11 communication; 1148typically by hearing a beacon frame from an access point operating 1149on the channel. 1150.Cm list freq 1151is another way of requesting this information. 1152By default a compacted list of channels is displayed; if the 1153.Fl v 1154option is specified then all channels are shown. 1155.It Cm list countries 1156Display the set of country codes and regulatory domains that can be 1157used in regulatory configuration. 1158.It Cm list mac 1159Display the current MAC Access Control List state. 1160Each address is prefixed with a character that indicates the 1161current policy applied to it: 1162.Ql + 1163indicates the address is allowed access, 1164.Ql - 1165indicates the address is denied access, 1166.Ql * 1167indicates the address is present but the current policy open 1168(so the ACL is not consulted). 1169.It Cm list mesh 1170Displays the mesh routing table, used for forwarding packets on a mesh 1171network. 1172.It Cm list regdomain 1173Display the current regulatory settings including the available channels 1174and transmit power caps. 1175.It Cm list roam 1176Display the parameters that govern roaming operation. 1177.It Cm list txparam 1178Display the parameters that govern transmit operation. 1179.It Cm list txpower 1180Display the transmit power caps for each channel. 1181.It Cm list scan 1182Display the access points and/or ad-hoc neighbors 1183located in the vicinity. 1184This information may be updated automatically by the adapter 1185with a 1186.Cm scan 1187request or through background scanning. 1188Depending on the capabilities of the stations the following 1189flags can be included in the output: 1190.Bl -tag -width 3n 1191.It Li A 1192Authorized. 1193Indicates that the station is permitted to send/receive data frames. 1194.It Li E 1195Extended Rate Phy (ERP). 1196Indicates that the station is operating in an 802.11g network 1197using extended transmit rates. 1198.It Li H 1199High Throughput (HT). 1200Indicates that the station is using HT transmit rates. 1201If a `+' follows immediately after then the station associated 1202using deprecated mechanisms supported only when 1203.Cm htcompat 1204is enabled. 1205.It Li P 1206Power Save. 1207Indicates that the station is operating in power save mode. 1208.It Li Q 1209Quality of Service (QoS). 1210Indicates that the station is using QoS encapsulation for 1211data frame. 1212QoS encapsulation is enabled only when WME mode is enabled. 1213.It Li T 1214Transitional Security Network (TSN). 1215Indicates that the station associated using TSN; see also 1216.Cm tsn 1217below. 1218.It Li W 1219Wi-Fi Protected Setup (WPS). 1220Indicates that the station associated using WPS. 1221.El 1222.Pp 1223By default interesting information elements captured from the neighboring 1224stations are displayed at the end of each row. 1225Possible elements include: 1226.Cm WME 1227(station supports WME), 1228.Cm WPA 1229(station supports WPA), 1230.Cm WPS 1231(station supports WPS), 1232.Cm RSN 1233(station supports 802.11i/RSN), 1234.Cm HTCAP 1235(station supports 802.11n/HT communication), 1236.Cm ATH 1237(station supports Atheros protocol extensions), 1238.Cm VEN 1239(station supports unknown vendor-specific extensions). 1240If the 1241.Fl v 1242flag is used all the information elements and their 1243contents will be shown. 1244Specifying the 1245.Fl v 1246flag also enables display of long SSIDs. 1247The 1248.Cm list ap 1249command is another way of requesting this information. 1250.It Cm list sta 1251When operating as an access point display the stations that are 1252currently associated. 1253When operating in ad-hoc mode display stations identified as 1254neighbors in the IBSS. 1255When operating in mesh mode display stations identified as 1256neighbors in the MBSS. 1257When operating in station mode display the access point. 1258Capabilities advertised by the stations are described under 1259the 1260.Cm scan 1261request. 1262Depending on the capabilities of the stations the following 1263flags can be included in the output: 1264.Bl -tag -width 3n 1265.It Li A 1266Authorized. 1267Indicates that the station is permitted to send/receive data frames. 1268.It Li E 1269Extended Rate Phy (ERP). 1270Indicates that the station is operating in an 802.11g network 1271using extended transmit rates. 1272.It Li H 1273High Throughput (HT). 1274Indicates that the station is using HT transmit rates. 1275If a `+' follows immediately after then the station associated 1276using deprecated mechanisms supported only when 1277.Cm htcompat 1278is enabled. 1279.It Li P 1280Power Save. 1281Indicates that the station is operating in power save mode. 1282.It Li Q 1283Quality of Service (QoS). 1284Indicates that the station is using QoS encapsulation for 1285data frame. 1286QoS encapsulation is enabled only when WME mode is enabled. 1287.It Li T 1288Transitional Security Network (TSN). 1289Indicates that the station associated using TSN; see also 1290.Cm tsn 1291below. 1292.It Li W 1293Wi-Fi Protected Setup (WPS). 1294Indicates that the station associated using WPS. 1295.El 1296.Pp 1297By default information elements received from associated stations 1298are displayed in a short form; the 1299.Fl v 1300flag causes this information to be displayed symbolically. 1301.It Cm list wme 1302Display the current channel parameters to use when operating in WME mode. 1303If the 1304.Fl v 1305option is specified then both channel and BSS parameters are displayed 1306for each AC (first channel, then BSS). 1307When WME mode is enabled for an adaptor this information will be 1308displayed with the regular status; this command is mostly useful 1309for examining parameters when WME mode is disabled. 1310See the description of the 1311.Cm wme 1312directive for information on the various parameters. 1313.It Cm maxretry Ar count 1314Set the maximum number of tries to use in sending unicast frames. 1315The default setting is 6 but drivers may override this with a value 1316they choose. 1317.It Cm mcastrate Ar rate 1318Set the rate for transmitting multicast/broadcast frames. 1319Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1320This rate should be valid for the current operating conditions; 1321if an invalid rate is specified drivers are free to chose an 1322appropriate rate. 1323.It Cm mgtrate Ar rate 1324Set the rate for transmitting management and/or control frames. 1325Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1326.It Cm outdoor 1327Set the location to use in calculating regulatory constraints. 1328The location is also advertised in beacon and probe response frames 1329when 802.11d is enabled with 1330.Cm dotd . 1331See also 1332.Cm anywhere , 1333.Cm country , 1334.Cm indoor , 1335and 1336.Cm regdomain . 1337.It Cm powersave 1338Enable powersave operation. 1339When operating as a client, the station will conserve power by 1340periodically turning off the radio and listening for 1341messages from the access point telling it there are packets waiting. 1342The station must then retrieve the packets. 1343Not all devices support power save operation as a client. 1344The 802.11 specification requires that all access points support 1345power save but some drivers do not. 1346Use 1347.Fl powersave 1348to disable powersave operation when operating as a client. 1349.It Cm powersavemode Ar mode 1350Set powersave mode. 1351The set of valid modes is 1352.Cm off 1353(same as 1354.Fl powersave ) , 1355.Cm on 1356(same as 1357.Cm powersave ) , 1358and 1359.Cm cam 1360(same as 1361.Cm powersave ) . 1362.It Cm powersavesleep Ar sleep 1363Set the desired max powersave sleep time in TU's (1024 usecs). 1364By default the max powersave sleep time is 100 TU's. 1365.It Cm protmode Ar technique 1366For interfaces operating in 802.11g, use the specified 1367.Ar technique 1368for protecting OFDM frames in a mixed 11b/11g network. 1369The set of valid techniques is 1370.Cm off , cts 1371(CTS to self), 1372and 1373.Cm rtscts 1374(RTS/CTS). 1375Technique names are case insensitive. 1376Not all devices support 1377.Cm cts 1378as a protection technique. 1379.It Cm pureg 1380When operating as an access point in 802.11g mode allow only 138111g-capable stations to associate (11b-only stations are not 1382permitted to associate). 1383To allow both 11g and 11b-only stations to associate, use 1384.Fl pureg . 1385.It Cm puren 1386When operating as an access point in 802.11n mode allow only 1387HT-capable stations to associate (legacy stations are not 1388permitted to associate). 1389To allow both HT and legacy stations to associate, use 1390.Fl puren . 1391.It Cm regdomain Ar sku 1392Set the regulatory domain to use in calculating the regulatory constraints 1393for operation. 1394In particular the set of available channels, how the wireless device 1395will operation on the channels, and the maximum transmit power that 1396can be used on a channel are defined by this setting. 1397Regdomain codes (SKU's) are taken from /etc/regdomain.xml and can also 1398be viewed with the ``list countries'' request. 1399Note that not all devices support changing the regdomain from a default 1400setting; typically stored in EEPROM. 1401See also 1402.Cm country , 1403.Cm indoor , 1404.Cm outdoor , 1405and 1406.Cm anywhere . 1407.It Cm rifs 1408Enable use of Reduced InterFrame Spacing (RIFS) when operating in 802.11n 1409on an HT channel. 1410Note that RIFS must be supported by both the station and access point 1411for it to be used. 1412To disable RIFS use 1413.Fl rifs . 1414.It Cm roam:rate Ar rate 1415Set the threshold for controlling roaming when operating in a BSS. 1416The 1417.Ar rate 1418parameter specifies the transmit rate in megabits 1419at which roaming should be considered. 1420If the current transmit rate drops below this setting and background scanning 1421is enabled, then the system will check if a more desirable access point is 1422available and switch over to it. 1423The current scan cache contents are used if they are considered 1424valid according to the 1425.Cm scanvalid 1426parameter; otherwise a background scan operation is triggered before 1427any selection occurs. 1428Each channel type has a separate rate threshold; the default values are: 142912 Mb/s (11a), 2 Mb/s (11b), 2 Mb/s (11g), MCS 1 (11na, 11ng). 1430.It Cm roam:rssi Ar rssi 1431Set the threshold for controlling roaming when operating in a BSS. 1432The 1433.Ar rssi 1434parameter specifies the receive signal strength in dBm units 1435at which roaming should be considered. 1436If the current rssi drops below this setting and background scanning 1437is enabled, then the system will check if a more desirable access point is 1438available and switch over to it. 1439The current scan cache contents are used if they are considered 1440valid according to the 1441.Cm scanvalid 1442parameter; otherwise a background scan operation is triggered before 1443any selection occurs. 1444Each channel type has a separate rssi threshold; the default values are 1445all 7 dBm. 1446.It Cm roaming Ar mode 1447When operating as a station, control how the system will 1448behave when communication with the current access point 1449is broken. 1450The 1451.Ar mode 1452argument may be one of 1453.Cm device 1454(leave it to the hardware device to decide), 1455.Cm auto 1456(handle either in the device or the operating system\[em]as appropriate), 1457.Cm manual 1458(do nothing until explicitly instructed). 1459By default, the device is left to handle this if it is 1460capable; otherwise, the operating system will automatically 1461attempt to reestablish communication. 1462Manual mode is used by applications such as 1463.Xr wpa_supplicant 8 1464that want to control the selection of an access point. 1465.It Cm rtsthreshold Ar length 1466Set the threshold for which 1467transmitted frames are preceded by transmission of an 1468RTS 1469control frame. 1470The 1471.Ar length 1472argument 1473is the frame size in bytes and must be in the range 1 to 2346. 1474Setting 1475.Ar length 1476to 1477.Li 2346 , 1478.Cm any , 1479or 1480.Cm - 1481disables transmission of RTS frames. 1482Not all adapters support setting the RTS threshold. 1483.It Cm scan 1484Initiate a scan of neighboring stations, wait for it to complete, and 1485display all stations found. 1486Only the super-user can initiate a scan. 1487See 1488.Cm list scan 1489for information on the display. 1490By default a background scan is done; otherwise a foreground 1491scan is done and the station may roam to a different access point. 1492The 1493.Cm list scan 1494request can be used to show recent scan results without 1495initiating a new scan. 1496.It Cm scanvalid Ar threshold 1497Set the maximum time the scan cache contents are considered valid; 1498i.e. will be used without first triggering a scan operation to 1499refresh the data. 1500The 1501.Ar threshold 1502parameter is specified in seconds and defaults to 60 seconds. 1503The minimum setting for 1504.Ar threshold 1505is 10 seconds. 1506One should take care setting this threshold; if it is set too low 1507then attempts to roam to another access point may trigger unnecessary 1508background scan operations. 1509.It Cm shortgi 1510Enable use of Short Guard Interval when operating in 802.11n 1511on an HT channel. 1512NB: this currently enables Short GI on both HT40 and HT20 channels. 1513To disable Short GI use 1514.Fl shortgi . 1515.It Cm smps 1516Enable use of Static Spatial Multiplexing Power Save (SMPS) 1517when operating in 802.11n. 1518A station operating with Static SMPS maintains only a single 1519receive chain active (this can significantly reduce power consumption). 1520To disable SMPS use 1521.Fl smps . 1522.It Cm smpsdyn 1523Enable use of Dynamic Spatial Multiplexing Power Save (SMPS) 1524when operating in 802.11n. 1525A station operating with Dynamic SMPS maintains only a single 1526receive chain active but switches to multiple receive chains when it 1527receives an RTS frame (this can significantly reduce power consumption). 1528Note that stations cannot distinguish between RTS/CTS intended to 1529enable multiple receive chains and those used for other purposes. 1530To disable SMPS use 1531.Fl smps . 1532.It Cm ssid Ar ssid 1533Set the desired Service Set Identifier (aka network name). 1534The SSID is a string up to 32 characters 1535in length and may be specified as either a normal string or in 1536hexadecimal when preceded by 1537.Ql 0x . 1538Additionally, the SSID may be cleared by setting it to 1539.Ql - . 1540.It Cm tdmaslot Ar slot 1541When operating with TDMA, use the specified 1542.Ar slot 1543configuration. 1544The 1545.Ar slot 1546is a number between 0 and the maximum number of slots in the BSS. 1547Note that a station configured as slot 0 is a master and 1548will broadcast beacon frames advertising the BSS; 1549stations configured to use other slots will always 1550scan to locate a master before they ever transmit. 1551By default 1552.Cm tdmaslot 1553is set to 1. 1554.It Cm tdmaslotcnt Ar cnt 1555When operating with TDMA, setup a BSS with 1556.Ar cnt 1557slots. 1558The slot count may be at most 8. 1559The current implementation is only tested with two stations 1560(i.e. point to point applications). 1561This setting is only meaningful when a station is configured as slot 0; 1562other stations adopt this setting from the BSS they join. 1563By default 1564.Cm tdmaslotcnt 1565is set to 2. 1566.It Cm tdmaslotlen Ar len 1567When operating with TDMA, setup a BSS such that each station has a slot 1568.Ar len 1569microseconds long. 1570The slot length must be at least 150 microseconds (1/8 TU) 1571and no more than 65 milliseconds. 1572Note that setting too small a slot length may result in poor channel 1573bandwidth utilization due to factors such as timer granularity and 1574guard time. 1575This setting is only meaningful when a station is configured as slot 0; 1576other stations adopt this setting from the BSS they join. 1577By default 1578.Cm tdmaslotlen 1579is set to 10 milliseconds. 1580.It Cm tdmabintval Ar intval 1581When operating with TDMA, setup a BSS such that beacons are transmitted every 1582.Ar intval 1583superframes to synchronize the TDMA slot timing. 1584A superframe is defined as the number of slots times the slot length; e.g. 1585a BSS with two slots of 10 milliseconds has a 20 millisecond superframe. 1586The beacon interval may not be zero. 1587A lower setting of 1588.Cm tdmabintval 1589causes the timers to be resynchronized more often; this can be help if 1590significant timer drift is observed. 1591By default 1592.Cm tdmabintval 1593is set to 5. 1594.It Cm tsn 1595When operating as an access point with WPA/802.11i allow legacy 1596stations to associate using static key WEP and open authentication. 1597To disallow legacy station use of WEP, use 1598.Fl tsn . 1599.It Cm txpower Ar power 1600Set the power used to transmit frames. 1601The 1602.Ar power 1603argument is specified in .5 dBm units. 1604Out of range values are truncated. 1605Typically only a few discreet power settings are available and 1606the driver will use the setting closest to the specified value. 1607Not all adapters support changing the transmit power. 1608.It Cm ucastrate Ar rate 1609Set a fixed rate for transmitting unicast frames. 1610Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1611This rate should be valid for the current operating conditions; 1612if an invalid rate is specified drivers are free to chose an 1613appropriate rate. 1614.It Cm wepmode Ar mode 1615Set the desired WEP mode. 1616Not all adapters support all modes. 1617The set of valid modes is 1618.Cm off , on , 1619and 1620.Cm mixed . 1621The 1622.Cm mixed 1623mode explicitly tells the adaptor to allow association with access 1624points which allow both encrypted and unencrypted traffic. 1625On these adapters, 1626.Cm on 1627means that the access point must only allow encrypted connections. 1628On other adapters, 1629.Cm on 1630is generally another name for 1631.Cm mixed . 1632Modes are case insensitive. 1633.It Cm weptxkey Ar index 1634Set the WEP key to be used for transmission. 1635This is the same as setting the default transmission key with 1636.Cm deftxkey . 1637.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 1638Set the selected WEP key. 1639If an 1640.Ar index 1641is not given, key 1 is set. 1642A WEP key will be either 5 or 13 1643characters (40 or 104 bits) depending of the local network and the 1644capabilities of the adaptor. 1645It may be specified either as a plain 1646string or as a string of hexadecimal digits preceded by 1647.Ql 0x . 1648For maximum portability, hex keys are recommended; 1649the mapping of text keys to WEP encryption is usually driver-specific. 1650In particular, the 1651.Tn Windows 1652drivers do this mapping differently to 1653.Fx . 1654A key may be cleared by setting it to 1655.Ql - . 1656If WEP is supported then there are at least four keys. 1657Some adapters support more than four keys. 1658If that is the case, then the first four keys 1659(1-4) will be the standard temporary keys and any others will be adaptor 1660specific keys such as permanent keys stored in NVRAM. 1661.Pp 1662Note that you must set a default transmit key with 1663.Cm deftxkey 1664for the system to know which key to use in encrypting outbound traffic. 1665.It Cm wme 1666Enable Wireless Multimedia Extensions (WME) support, if available, 1667for the specified interface. 1668WME is a subset of the IEEE 802.11e standard to support the 1669efficient communication of realtime and multimedia data. 1670To disable WME support, use 1671.Fl wme . 1672Another name for this parameter is 1673.Cm wmm . 1674.Pp 1675The following parameters are meaningful only when WME support is in use. 1676Parameters are specified per-AC (Access Category) and 1677split into those that are used by a station when acting 1678as an access point and those for client stations in the BSS. 1679The latter are received from the access point and may not be changed 1680(at the station). 1681The following Access Categories are recognized: 1682.Pp 1683.Bl -tag -width ".Cm AC_BK" -compact 1684.It Cm AC_BE 1685(or 1686.Cm BE ) 1687best effort delivery, 1688.It Cm AC_BK 1689(or 1690.Cm BK ) 1691background traffic, 1692.It Cm AC_VI 1693(or 1694.Cm VI ) 1695video traffic, 1696.It Cm AC_VO 1697(or 1698.Cm VO ) 1699voice traffic. 1700.El 1701.Pp 1702AC parameters are case-insensitive. 1703Traffic classification is done in the operating system using the 1704vlan priority associated with data frames or the 1705ToS (Type of Service) indication in IP-encapsulated frames. 1706If neither information is present, traffic is assigned to the 1707Best Effort (BE) category. 1708.Bl -tag -width indent 1709.It Cm ack Ar ac 1710Set the ACK policy for QoS transmissions by the local station; 1711this controls whether or not data frames transmitted by a station 1712require an ACK response from the receiving station. 1713To disable waiting for an ACK use 1714.Fl ack . 1715This parameter is applied only to the local station. 1716.It Cm acm Ar ac 1717Enable the Admission Control Mandatory (ACM) mechanism 1718for transmissions by the local station. 1719To disable the ACM use 1720.Fl acm . 1721On stations in a BSS this parameter is read-only and indicates 1722the setting received from the access point. 1723NB: ACM is not supported right now. 1724.It Cm aifs Ar ac Ar count 1725Set the Arbitration Inter Frame Spacing (AIFS) 1726channel access parameter to use for transmissions 1727by the local station. 1728On stations in a BSS this parameter is read-only and indicates 1729the setting received from the access point. 1730.It Cm cwmin Ar ac Ar count 1731Set the CWmin channel access parameter to use for transmissions 1732by the local station. 1733On stations in a BSS this parameter is read-only and indicates 1734the setting received from the access point. 1735.It Cm cwmax Ar ac Ar count 1736Set the CWmax channel access parameter to use for transmissions 1737by the local station. 1738On stations in a BSS this parameter is read-only and indicates 1739the setting received from the access point. 1740.It Cm txoplimit Ar ac Ar limit 1741Set the Transmission Opportunity Limit channel access parameter 1742to use for transmissions by the local station. 1743This parameter defines an interval of time when a WME station 1744has the right to initiate transmissions onto the wireless medium. 1745On stations in a BSS this parameter is read-only and indicates 1746the setting received from the access point. 1747.It Cm bss:aifs Ar ac Ar count 1748Set the AIFS channel access parameter to send to stations in a BSS. 1749This parameter is meaningful only when operating in ap mode. 1750.It Cm bss:cwmin Ar ac Ar count 1751Set the CWmin channel access parameter to send to stations in a BSS. 1752This parameter is meaningful only when operating in ap mode. 1753.It Cm bss:cwmax Ar ac Ar count 1754Set the CWmax channel access parameter to send to stations in a BSS. 1755This parameter is meaningful only when operating in ap mode. 1756.It Cm bss:txoplimit Ar ac Ar limit 1757Set the TxOpLimit channel access parameter to send to stations in a BSS. 1758This parameter is meaningful only when operating in ap mode. 1759.El 1760.It Cm wps 1761Enable Wireless Privacy Subscriber support. 1762Note that WPS support requires a WPS-capable supplicant. 1763To disable this function use 1764.Fl wps . 1765.El 1766.Pp 1767The following parameters support an optional access control list 1768feature available with some adapters when operating in ap mode; see 1769.Xr wlan_acl 4 . 1770This facility allows an access point to accept/deny association 1771requests based on the MAC address of the station. 1772Note that this feature does not significantly enhance security 1773as MAC address spoofing is easy to do. 1774.Bl -tag -width indent 1775.It Cm mac:add Ar address 1776Add the specified MAC address to the database. 1777Depending on the policy setting association requests from the 1778specified station will be allowed or denied. 1779.It Cm mac:allow 1780Set the ACL policy to permit association only by 1781stations registered in the database. 1782.It Cm mac:del Ar address 1783Delete the specified MAC address from the database. 1784.It Cm mac:deny 1785Set the ACL policy to deny association only by 1786stations registered in the database. 1787.It Cm mac:kick Ar address 1788Force the specified station to be deauthenticated. 1789This typically is done to block a station after updating the 1790address database. 1791.It Cm mac:open 1792Set the ACL policy to allow all stations to associate. 1793.It Cm mac:flush 1794Delete all entries in the database. 1795.It Cm mac:radius 1796Set the ACL policy to permit association only by 1797stations approved by a RADIUS server. 1798Note that this feature requires the 1799.Xr hostapd 8 1800program be configured to do the right thing 1801as it handles the RADIUS processing 1802(and marks stations as authorized). 1803.El 1804.Pp 1805The following parameters are related to a wireless interface operating in mesh 1806mode: 1807.Bl -tag -width indent 1808.It Cm meshid Ar meshid 1809Set the desired Mesh Identifier. 1810The Mesh ID is a string up to 32 characters in length. 1811A mesh interface must have a Mesh Identifier specified 1812to reach an operational state. 1813.It Cm meshttl Ar ttl 1814Set the desired ``time to live'' for mesh forwarded packets; 1815this is the number of hops a packet may be forwarded before 1816it is discarded. 1817The default setting for 1818.Cm meshttl 1819is 31. 1820.It Cm meshpeering 1821Enable or disable peering with neighbor mesh stations. 1822Stations must peer before any data packets can be exchanged. 1823By default 1824.Cm meshpeering 1825is enabled. 1826.It Cm meshforward 1827Enable or disable forwarding packets by a mesh interface. 1828By default 1829.Cm meshforward 1830is enabled. 1831.It Cm meshmetric Ar protocol 1832Set the specified 1833.Ar protocol 1834as the link metric protocol used on a mesh network. 1835The default protocol is called 1836.Ar AIRTIME . 1837The mesh interface will restart after changing this setting. 1838.It Cm meshpath Ar protocol 1839Set the specified 1840.Ar protocol 1841as the path selection protocol used on a mesh network. 1842The only available protocol at the moment is called 1843.Ar HWMP 1844(Hybrid Wireless Mesh Protocol). 1845The mesh interface will restart after changing this setting. 1846.It Cm hwmprootmode Ar mode 1847Stations on a mesh network can operate as ``root nodes.'' 1848Root nodes try to find paths to all mesh nodes and advertise themselves 1849regularly. 1850When there is a root mesh node on a network, other mesh nodes can setup 1851paths between themselves faster because they can use the root node 1852to find the destination. 1853This path may not be the best, but on-demand 1854routing will eventually find the best path. 1855The following modes are recognized: 1856.Pp 1857.Bl -tag -width ".Cm PROACTIVE" -compact 1858.It Cm DISABLED 1859Disable root mode. 1860.It Cm NORMAL 1861Send broadcast path requests every two seconds. 1862Nodes on the mesh without a path to this root mesh station with try to 1863discover a path to us. 1864.It Cm PROACTIVE 1865Send broadcast path requests every two seconds and every node must reply 1866with a path reply even if it already has a path to this root mesh station, 1867.It Cm RANN 1868Send broadcast root announcement (RANN) frames. 1869Nodes on the mesh without a path to this root mesh station with try to 1870discover a path to us. 1871.El 1872By default 1873.Cm hwmprootmode 1874is set to 1875.Ar DISABLED . 1876.It Cm hwmpmaxhops Ar cnt 1877Set the maximum number of hops allowed in an HMWP path to 1878.Ar cnt . 1879The default setting for 1880.Cm hwmpmaxhops 1881is 31. 1882.El 1883.Pp 1884The following parameters are for compatibility with other systems: 1885.Bl -tag -width indent 1886.It Cm nwid Ar ssid 1887Another name for the 1888.Cm ssid 1889parameter. 1890Included for 1891.Nx 1892compatibility. 1893.It Cm stationname Ar name 1894Set the name of this station. 1895The station name is not part of the IEEE 802.11 1896protocol though some interfaces support it. 1897As such it only 1898seems to be meaningful to identical or virtually identical equipment. 1899Setting the station name is identical in syntax to setting the SSID. 1900One can also use 1901.Cm station 1902for 1903.Bsx 1904compatibility. 1905.It Cm wep 1906Another way of saying 1907.Cm wepmode on . 1908Included for 1909.Bsx 1910compatibility. 1911.It Fl wep 1912Another way of saying 1913.Cm wepmode off . 1914Included for 1915.Bsx 1916compatibility. 1917.It Cm nwkey key 1918Another way of saying: 1919.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 1920Included for 1921.Nx 1922compatibility. 1923.It Cm nwkey Xo 1924.Sm off 1925.Ar n : k1 , k2 , k3 , k4 1926.Sm on 1927.Xc 1928Another way of saying 1929.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 1930Included for 1931.Nx 1932compatibility. 1933.It Fl nwkey 1934Another way of saying 1935.Cm wepmode off . 1936Included for 1937.Nx 1938compatibility. 1939.El 1940.Pp 1941The following parameters are specific to bridge interfaces: 1942.Bl -tag -width indent 1943.It Cm addm Ar interface 1944Add the interface named by 1945.Ar interface 1946as a member of the bridge. 1947The interface is put into promiscuous mode 1948so that it can receive every packet sent on the network. 1949.It Cm deletem Ar interface 1950Remove the interface named by 1951.Ar interface 1952from the bridge. 1953Promiscuous mode is disabled on the interface when 1954it is removed from the bridge. 1955.It Cm maxaddr Ar size 1956Set the size of the bridge address cache to 1957.Ar size . 1958The default is 100 entries. 1959.It Cm timeout Ar seconds 1960Set the timeout of address cache entries to 1961.Ar seconds 1962seconds. 1963If 1964.Ar seconds 1965is zero, then address cache entries will not be expired. 1966The default is 1200 seconds. 1967.It Cm addr 1968Display the addresses that have been learned by the bridge. 1969.It Cm static Ar interface-name Ar address 1970Add a static entry into the address cache pointing to 1971.Ar interface-name . 1972Static entries are never aged out of the cache or re-placed, even if the 1973address is seen on a different interface. 1974.It Cm deladdr Ar address 1975Delete 1976.Ar address 1977from the address cache. 1978.It Cm flush 1979Delete all dynamically-learned addresses from the address cache. 1980.It Cm flushall 1981Delete all addresses, including static addresses, from the address cache. 1982.It Cm discover Ar interface 1983Mark an interface as a 1984.Dq discovering 1985interface. 1986When the bridge has no address cache entry 1987(either dynamic or static) 1988for the destination address of a packet, 1989the bridge will forward the packet to all 1990member interfaces marked as 1991.Dq discovering . 1992This is the default for all interfaces added to a bridge. 1993.It Fl discover Ar interface 1994Clear the 1995.Dq discovering 1996attribute on a member interface. 1997For packets without the 1998.Dq discovering 1999attribute, the only packets forwarded on the interface are broadcast 2000or multicast packets and packets for which the destination address 2001is known to be on the interface's segment. 2002.It Cm learn Ar interface 2003Mark an interface as a 2004.Dq learning 2005interface. 2006When a packet arrives on such an interface, the source 2007address of the packet is entered into the address cache as being a 2008destination address on the interface's segment. 2009This is the default for all interfaces added to a bridge. 2010.It Fl learn Ar interface 2011Clear the 2012.Dq learning 2013attribute on a member interface. 2014.It Cm span Ar interface 2015Add the interface named by 2016.Ar interface 2017as a span port on the bridge. 2018Span ports transmit a copy of every frame received by the bridge. 2019This is most useful for snooping a bridged network passively on 2020another host connected to one of the span ports of the bridge. 2021.It Fl span Ar interface 2022Delete the interface named by 2023.Ar interface 2024from the list of span ports of the bridge. 2025.It Cm stp Ar interface 2026Enable Spanning Tree protocol on 2027.Ar interface . 2028The 2029.Xr bridge 4 2030driver has support for the IEEE 802.1D Spanning Tree protocol (STP). 2031Spanning Tree is used to detect and remove loops in a network topology. 2032.It Fl stp Ar interface 2033Disable Spanning Tree protocol on 2034.Ar interface . 2035This is the default for all interfaces added to a bridge. 2036.It Cm maxage Ar seconds 2037Set the time that a Spanning Tree protocol configuration is valid. 2038The default is 20 seconds. 2039The minimum is 1 second and the maximum is 255 seconds. 2040.It Cm fwddelay Ar seconds 2041Set the time that must pass before an interface begins forwarding 2042packets when Spanning Tree is enabled. 2043The default is 15 seconds. 2044The minimum is 1 second and the maximum is 255 seconds. 2045.It Cm hellotime Ar seconds 2046Set the time between broadcasting of Spanning Tree protocol 2047configuration messages. 2048The default is 2 seconds. 2049The minimum is 1 second and the maximum is 255 seconds. 2050.It Cm priority Ar value 2051Set the bridge priority for Spanning Tree. 2052The default is 32768. 2053The minimum is 0 and the maximum is 65536. 2054.It Cm ifpriority Ar interface Ar value 2055Set the Spanning Tree priority of 2056.Ar interface 2057to 2058.Ar value . 2059The default is 128. 2060The minimum is 0 and the maximum is 255. 2061.Pp 2062The priority is used to select which interface out of all 2063forwarding and bonded interfaces with the same MAC 2064to output a packet on whe 2065.Cm link2 2066mode is not being used. 2067Note that interfaces in the 'blocking' state do not participate 2068in the priority selection. 2069If the priorities are the same on a non-bonded member, the 2070designated member will be used. 2071.It Cm ifpathcost Ar interface Ar value 2072Set the Spanning Tree path cost of 2073.Ar interface 2074to 2075.Ar value . 2076The default is 55. 2077The minimum is 0 and the maximum is 65535. 2078.Pp 2079The path cost is added to both incoming and outgoing packets on the 2080member, lower values will make the member more valuable. 2081.It Cm ifbondweight Ar interface Ar value 2082Set the number of packets to output on a bonded member before 2083round-robining to the next member. 2084The default is 1. 2085Larger values or different values for each member can be used 2086if bursting would be beneficial or if the outgoing bandwidth 2087on each of the members is asymmetric. 2088For example, one specify a value of 6 on tap0 and 4 on tap1 2089for a 6:4 ratio. 2090Remember that this also controls packet bursting. 2091.It Cm link0 2092The link0 option enables transparent bridging mode. 2093The bridge will make every effort to retain the ethernet header 2094when forwarding packets between interfaces, making the bridging 2095function work more like a hardware bridge device. 2096.It Cm link1 2097The link1 option enables keepalive transmission and automatically 2098places a member into a special blocked mode if no keepalive reception 2099occurs. 2100If either sides of the link uses this option then both sides must use 2101this option. 2102This option is impemented by sending CFG updates on the hello interval 2103to the remote. 2104The link is considered lost after 10 intervals (typically 20 seconds). 2105.It Cm link2 2106The link2 option enables channel bonding (see also ifbondweight). 2107All member interfaces with the same mac address are considered to 2108be in a bonding group. 2109When something like 2110.Xr tap 4 2111is used, you can manually control or copy the mac to create bonding groups. 2112When interface bonding is enabled normally blocked interfaces belonging 2113to the same bonding group as an active forwarding interface will be 2114changed to the bonding state. 2115Both sides of link the member represents must operate in bonding mode 2116for this to work, otherwise the remote end may decide to throw away 2117half your packets. 2118.El 2119.Pp 2120The following parameters are specific to IP tunnel interfaces, 2121.Xr gif 4 : 2122.Bl -tag -width indent 2123.It Cm tunnel Ar src_addr dest_addr 2124Configure the physical source and destination address for IP tunnel 2125interfaces. 2126The arguments 2127.Ar src_addr 2128and 2129.Ar dest_addr 2130are interpreted as the outer source/destination for the encapsulating 2131IPv4/IPv6 header. 2132.It Fl tunnel 2133Unconfigure the physical source and destination address for IP tunnel 2134interfaces previously configured with 2135.Cm tunnel . 2136.It Cm deletetunnel 2137Another name for the 2138.Fl tunnel 2139parameter. 2140.El 2141.Pp 2142The following parameters are specific to 2143.Xr vlan 4 2144interfaces: 2145.Bl -tag -width indent 2146.It Cm vlan Ar vlan_tag 2147Set the VLAN tag value to 2148.Ar vlan_tag . 2149This value is a 16-bit number which is used to create an 802.1Q 2150VLAN header for packets sent from the 2151.Xr vlan 4 2152interface. 2153Note that 2154.Cm vlan 2155and 2156.Cm vlandev 2157must both be set at the same time. 2158.It Cm vlandev Ar iface 2159Associate the physical interface 2160.Ar iface 2161with a 2162.Xr vlan 4 2163interface. 2164Packets transmitted through the 2165.Xr vlan 4 2166interface will be 2167diverted to the specified physical interface 2168.Ar iface 2169with 802.1Q VLAN encapsulation. 2170Packets with 802.1Q encapsulation received 2171by the parent interface with the correct VLAN tag will be diverted to 2172the associated 2173.Xr vlan 4 2174pseudo-interface. 2175The 2176.Xr vlan 4 2177interface is assigned a 2178copy of the parent interface's flags and the parent's ethernet address. 2179The 2180.Cm vlandev 2181and 2182.Cm vlan 2183must both be set at the same time. 2184If the 2185.Xr vlan 4 2186interface already has 2187a physical interface associated with it, this command will fail. 2188To 2189change the association to another physical interface, the existing 2190association must be cleared first. 2191.Pp 2192Note: if the hardware tagging capability 2193is set on the parent interface, the 2194.Xr vlan 4 2195pseudo 2196interface's behavior changes: 2197the 2198.Xr vlan 4 2199interface recognizes that the 2200parent interface supports insertion and extraction of VLAN tags on its 2201own (usually in firmware) and that it should pass packets to and from 2202the parent unaltered. 2203.It Fl vlandev Op Ar iface 2204If the driver is a 2205.Xr vlan 4 2206pseudo device, disassociate the parent interface from it. 2207This breaks the link between the 2208.Xr vlan 4 2209interface and its parent, 2210clears its VLAN tag, flags and its link address and shuts the interface down. 2211The 2212.Ar iface 2213argument is useless and hence deprecated. 2214.El 2215.Pp 2216The following parameters are specific to 2217.Xr carp 4 2218interfaces: 2219.Bl -tag -width indent 2220.It Cm advbase Ar seconds 2221Specifies the base of the advertisement interval in seconds. 2222The acceptable values are 1 to 255. 2223The default value is 1. 2224.\" The default value is 2225.\" .Dv CARP_DFLTINTV . 2226.It Cm advskew Ar interval 2227Specifies the skew to add to the base advertisement interval to 2228make one host advertise slower than another host. 2229It is specified in 1/256 of seconds. 2230The acceptable values are 1 to 254. 2231The default value is 0. 2232.It Cm pass Ar phrase 2233Set the authentication key to 2234.Ar phrase . 2235.It Cm vhid Ar n 2236Set the virtual host ID. 2237This is a required setting. 2238Acceptable values are 1 to 255. 2239.El 2240.Pp 2241The 2242.Nm 2243utility displays the current configuration for a network interface 2244when no optional parameters are supplied. 2245If a protocol family is specified, 2246.Nm 2247will report only the details specific to that protocol family. 2248.Pp 2249If the 2250.Fl m 2251flag is passed before an interface name, 2252.Nm 2253will display the capability list, 2254the maximum amount of data 2255that TCP segmentation offloading is allowed to aggregate and 2256all of the supported media for the specified interface. 2257If 2258.Fl L 2259flag is supplied, address lifetime is displayed for IPv6 addresses, 2260as time offset string. 2261.Pp 2262Optionally, the 2263.Fl a 2264flag may be used instead of an interface name. 2265This flag instructs 2266.Nm 2267to display information about all interfaces in the system. 2268The 2269.Fl d 2270flag limits this to interfaces that are down, and 2271.Fl u 2272limits this to interfaces that are up. 2273When no arguments are given, 2274.Fl a 2275is implied. 2276.Pp 2277The 2278.Fl l 2279flag may be used to list all available interfaces on the system, with 2280no other additional information. 2281Use of this flag is mutually exclusive 2282with all other flags and commands, except for 2283.Fl d 2284(only list interfaces that are down) 2285and 2286.Fl u 2287(only list interfaces that are up). 2288.Pp 2289The 2290.Fl v 2291flag may be used to get more verbose status for an interface. 2292.Pp 2293The 2294.Fl C 2295flag may be used to list all of the interface cloners available on 2296the system, with no additional information. 2297Use of this flag is mutually exclusive with all other flags and commands. 2298.Pp 2299The 2300.Fl k 2301flag causes keying information for the interface, if available, to be 2302printed. 2303For example, the values of 802.11 WEP keys will be printed, if accessible to 2304the current user. 2305This information is not printed by default, as it may be considered 2306sensitive. 2307.Pp 2308Only the super-user may modify the configuration of a network interface. 2309.Sh DIAGNOSTICS 2310Messages indicating the specified interface does not exist, the 2311requested address is unknown, or the user is not privileged and 2312tried to alter an interface's configuration. 2313.Sh SEE ALSO 2314.Xr netstat 1 , 2315.Xr carp 4 , 2316.Xr ifmedia 4 , 2317.Xr netintro 4 , 2318.Xr polling 4 , 2319.Xr vlan 4 , 2320.\" .Xr eon 5 , 2321.Xr rc 8 , 2322.Xr routed 8 , 2323.Xr sysctl 8 2324.Sh HISTORY 2325The 2326.Nm 2327utility appeared in 2328.Bx 4.2 . 2329.Sh BUGS 2330Basic IPv6 node operation requires a link-local address on each 2331interface configured for IPv6. 2332Normally, such an address is automatically configured by the 2333kernel on each interface added to the system; this behaviour may 2334be disabled by setting the sysctl MIB variable 2335.Va net.inet6.ip6.auto_linklocal 2336to 0. 2337.Pp 2338If you delete such an address using 2339.Nm , 2340the kernel may act very odd. 2341Do this at your own risk. 2342