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 27, 2018 32.Dt IFCONFIG 8 33.Os 34.Sh NAME 35.Nm ifconfig 36.Nd configure network interface parameters 37.Sh SYNOPSIS 38.Nm 39.Op Fl L 40.Op Fl k 41.Op Fl m 42.Op Fl n 43.Ar interface 44.Op Cm create 45.Op Ar address_family 46.Oo 47.Ar address 48.Op Ar dest_address 49.Oc 50.Op Ar parameters 51.Nm 52.Op Fl n 53.Ar interface 54.Cm destroy 55.Nm 56.Fl a 57.Op Fl L 58.Op Fl d 59.Op Fl m 60.Op Fl u 61.Op Fl v 62.Op Ar address_family 63.Nm 64.Fl l 65.Op Fl d 66.Op Fl u 67.Op Ar address_family 68.Nm 69.Op Fl L 70.Op Fl d 71.Op Fl k 72.Op Fl m 73.Op Fl u 74.Op Fl v 75.Op Fl C 76.Nm 77.Op Fl g Ar groupname 78.Sh DESCRIPTION 79The 80.Nm 81utility is used to assign an address 82to a network interface and/or configure 83network interface parameters. 84The 85.Nm 86utility must be used at boot time to define the network address 87of each interface present on a machine; it may also be used at 88a later time to redefine an interface's address 89or other operating parameters. 90.Pp 91The following options are available: 92.Bl -tag -width indent 93.It Ar address 94For the 95.Tn DARPA Ns -Internet 96family, 97the address is either a host name present in the host name data 98base, 99.Xr hosts 5 , 100or a 101.Tn DARPA 102Internet address expressed in the Internet standard 103.Dq dot notation . 104.Pp 105It is also possible to use the CIDR notation (also known as the 106slash notation) to include the netmask. 107That is, one can specify an address like 108.Li 192.168.0.1/16 . 109.Pp 110For 111.Dq inet6 112family, it is also possible to specify the prefix length using the slash 113notation, like 114.Li ::1/128 . 115See the 116.Cm prefixlen 117parameter below for more information. 118.\" For the Xerox Network Systems(tm) family, 119.\" addresses are 120.\" .Ar net:a.b.c.d.e.f , 121.\" where 122.\" .Ar net 123.\" is the assigned network number (in decimal), 124.\" and each of the six bytes of the host number, 125.\" .Ar a 126.\" through 127.\" .Ar f , 128.\" are specified in hexadecimal. 129.\" The host number may be omitted on IEEE 802 protocol 130.\" (Ethernet, FDDI, and Token Ring) interfaces, 131.\" which use the hardware physical address, 132.\" and on interfaces other than the first. 133.\" For the 134.\" .Tn ISO 135.\" family, addresses are specified as a long hexadecimal string, 136.\" as in the Xerox family. 137.\" However, two consecutive dots imply a zero 138.\" byte, and the dots are optional, if the user wishes to (carefully) 139.\" count out long strings of digits in network byte order. 140.Pp 141The link-level 142.Pq Dq link 143address 144is specified as a series of colon-separated hex digits. 145This can be used to 146e.g.\& set a new MAC address on an ethernet interface, though the 147mechanism used is not ethernet-specific. 148If the interface is already 149up when this option is used, it will be briefly brought down and 150then brought back up again in order to ensure that the receive 151filter in the underlying ethernet hardware is properly reprogrammed. 152.It Ar address_family 153Specify the 154address family 155which affects interpretation of the remaining parameters. 156Since an interface can receive transmissions in differing protocols 157with different naming schemes, specifying the address family is recommended. 158The address or protocol families currently 159supported are 160.Dq inet , 161.Dq inet6 , 162.Dq atalk , 163and 164.Dq link . 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.It Ar groupname 182List the interfaces in the given group. 183.El 184.Pp 185The following parameters may be set with 186.Nm : 187.Bl -tag -width indent 188.It Cm add 189Another name for the 190.Cm alias 191parameter. 192Introduced for compatibility 193with 194.Bsx . 195.It Cm alias 196Establish an additional network address for this interface. 197This is sometimes useful when changing network numbers, and 198one wishes to accept packets addressed to the old interface. 199If the address is on the same subnet as the first network address 200for this interface, a non-conflicting netmask must be given. 201Usually 202.Li 0xffffffff 203is most appropriate. 204.It Fl alias 205Remove the network address specified. 206This would be used if you incorrectly specified an alias, or it 207was no longer needed. 208If you have incorrectly set an NS address having the side effect 209of specifying the host portion, removing all NS addresses will 210allow you to respecify the host portion. 211.It Cm anycast 212(Inet6 only.) 213Specify that the address configured is an anycast address. 214Based on the current specification, 215only routers may configure anycast addresses. 216Anycast address will not be used as source address of any of outgoing 217IPv6 packets. 218.It Cm arp 219Enable the use of the Address Resolution Protocol 220.Pq Xr arp 4 221in mapping 222between network level addresses and link level addresses (default). 223This is currently implemented for mapping between 224.Tn DARPA 225Internet 226addresses and 227.Tn IEEE 228802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). 229.It Fl arp 230Disable the use of the Address Resolution Protocol 231.Pq Xr arp 4 . 232.It Cm staticarp 233If the Address Resolution Protocol is enabled, 234the host will only reply to requests for its addresses, 235and will never send any requests. 236.It Fl staticarp 237If the Address Resolution Protocol is enabled, 238the host will perform normally, 239sending out requests and listening for replies. 240.It Cm broadcast 241(Inet only.) 242Specify the address to use to represent broadcasts to the 243network. 244The default broadcast address is the address with a host part of all 1's. 245.It Cm debug 246Enable driver dependent debugging code; usually, this turns on 247extra console error logging. 248.It Fl debug 249Disable driver dependent debugging code. 250.It Cm promisc 251Put interface into permanently promiscuous mode. 252.It Fl promisc 253Disable permanently promiscuous mode. 254.It Cm delete 255Another name for the 256.Fl alias 257parameter. 258.It Cm down 259Mark an interface 260.Dq down . 261When an interface is marked 262.Dq down , 263the system will not attempt to 264transmit messages through that interface. 265If possible, the interface will be reset to disable reception as well. 266This action does not automatically disable routes using the interface. 267.It Cm group Ar group-name 268Assign the interface to a 269.Dq group . 270Any interface can be in multiple groups. 271.Pp 272Cloned interfaces are members of their interface family group by default. 273For example, a PPP interface such as 274.Em ppp0 275is a member of the PPP interface family group, 276.Em ppp . 277.\" The interface(s) that the default route(s) point to are members of the 278.\" .Em egress 279.\" interface group. 280.It Cm -group Ar group-name 281Remove the interface from the given 282.Dq group . 283.It Cm eui64 284(Inet6 only.) 285Fill interface index 286(lowermost 64bit of an IPv6 address) 287automatically. 288.It Cm media Ar type 289If the driver supports the media selection system, set the media type 290of the interface to 291.Ar type . 292Some interfaces support the mutually exclusive use of one of several 293different physical media connectors. 294For example, a 10Mbit/s Ethernet 295interface might support the use of either 296.Tn AUI 297or twisted pair connectors. 298Setting the media type to 299.Cm 10base5/AUI 300would change the currently active connector to the AUI port. 301Setting it to 302.Cm 10baseT/UTP 303would activate twisted pair. 304Refer to the interfaces' driver 305specific documentation or man page for a complete list of the 306available types. 307.It Cm mediaopt Ar opts 308If the driver supports the media selection system, set the specified 309media options on the interface. 310The 311.Ar opts 312argument 313is a comma delimited list of options to apply to the interface. 314Refer to the interfaces' driver specific man page for a complete 315list of available options. 316.It Fl mediaopt Ar opts 317If the driver supports the media selection system, disable the 318specified media options on the interface. 319.It Cm mode Ar mode 320If the driver supports the media selection system, set the specified 321operating mode on the interface to 322.Ar mode . 323For IEEE 802.11 wireless interfaces that support multiple operating modes 324this directive is used to select between 802.11a 325.Pq Cm 11a , 326802.11b 327.Pq Cm 11b , 328and 802.11g 329.Pq Cm 11g 330operating modes. 331.It Cm name Ar name 332Set the interface name to 333.Ar name . 334.It Cm rss 335If the driver supports receive side scaling, 336enable receive side scaling on the interface. 337.It Fl rss 338If the driver supports receive side scaling, 339disable receive side scaling on the interface. 340.It Cm rxcsum , txcsum 341If the driver supports user-configurable checksum offloading, 342enable receive (or transmit) checksum offloading on the interface. 343Some drivers may not be able to enable these flags independently 344of each other, so setting one may also set the other. 345The driver will offload as much checksum work as it can reliably 346support, the exact level of offloading varies between drivers. 347.It Fl rxcsum , txcsum 348If the driver supports user-configurable checksum offloading, 349disable receive (or transmit) checksum offloading on the interface. 350These settings may not always be independent of each other. 351.It Cm tso 352If the driver supports TCP segmentation offloading, 353enable TCP segmentation offloading on the interface. 354.It Fl tso 355If the driver supports TCP segmentation offloading, 356disable TCP segmentation offloading on the interface. 357.It Cm vlanmtu , vlanhwtag 358If the driver offers user-configurable VLAN support, enable 359reception of extended frames or tag processing in hardware, 360respectively. 361Note that this must be issued on a physical interface associated with 362.Xr vlan 4 , 363not on a 364.Xr vlan 4 365interface itself. 366.It Fl vlanmtu , vlanhwtag 367If the driver offers user-configurable VLAN support, disable 368reception of extended frames or tag processing in hardware, 369respectively. 370.It Cm pollcpu Ar cpu 371Deprecated, use polling or npolling instead. 372.It Cm polling , npolling 373Turn on 374.Xr polling 4 375feature and disable interrupts on the interface, if the driver supports 376this mode. 377.It Fl polling , npolling 378Turn off 379.Xr polling 4 380feature and enable interrupt mode on the interface. 381.It Cm create 382Create the specified network pseudo-device. 383If the interface is given without a unit number, try to create a new 384device with an arbitrary unit number. 385If creation of an arbitrary device is successful, the new device name is 386printed to standard output unless the interface is renamed or destroyed 387in the same 388.Nm 389invocation. 390.It Cm destroy 391Destroy the specified network pseudo-device. 392.It Cm plumb 393Another name for the 394.Cm create 395parameter. 396Included for 397.Tn Solaris 398compatibility. 399.It Cm unplumb 400Another name for the 401.Cm destroy 402parameter. 403Included for 404.Tn Solaris 405compatibility. 406.It Cm metric Ar n 407Set the routing metric of the interface to 408.Ar n , 409default 0. 410The routing metric is used by the routing protocol 411.Pq Xr routed 8 . 412Higher metrics have the effect of making a route 413less favorable; metrics are counted as additional hops 414to the destination network or host. 415.It Cm mtu Ar n 416Set the maximum transmission unit of the interface to 417.Ar n , 418default is interface specific. 419The MTU is used to limit the size of packets that are transmitted on an 420interface. 421Not all interfaces support setting the MTU, and some interfaces have 422range restrictions. 423.It Cm tsolen Ar n 424Set the maximum amount of data 425that TCP segmentation offloading is allowed to aggregate to 426.Ar n , 427the default value is interface specific. 428This setting only takes effect on interfaces 429that support TCP segmentation offloading. 430.It Cm netmask Ar mask 431.\" (Inet and ISO.) 432(Inet only.) 433Specify how much of the address to reserve for subdividing 434networks into sub-networks. 435The mask includes the network part of the local address 436and the subnet part, which is taken from the host field of the address. 437The mask can be specified as a single hexadecimal number 438with a leading 439.Ql 0x , 440with a dot-notation Internet address, 441or with a pseudo-network name listed in the network table 442.Xr networks 5 . 443The mask contains 1's for the bit positions in the 32-bit address 444which are to be used for the network and subnet parts, 445and 0's for the host part. 446The mask should contain at least the standard network portion, 447and the subnet field should be contiguous with the network 448portion. 449.Pp 450The netmask can also be specified in CIDR notation after the address. 451See the 452.Ar address 453option above for more information. 454.It Cm autoconf 455(Inet6 only.) 456Enable autoconfiguration. 457.It Fl autoconf 458Disable autoconfiguration. 459.It Cm pltime Ar n 460(Inet6 only.) 461Set preferred lifetime for the address. 462.It Cm vltime Ar n 463(Inet6 only.) 464Set valid lifetime for the address. 465.It Cm prefixlen Ar len 466(Inet6 only.) 467Specify that 468.Ar len 469bits are reserved for subdividing networks into sub-networks. 470The 471.Ar len 472must be integer, and for syntactical reason it must be between 0 to 128. 473It is almost always 64 under the current IPv6 assignment rule. 474If the parameter is omitted, 64 is used. 475.Pp 476The prefix can also be specified using the slash notation after the address. 477See the 478.Ar address 479option above for more information. 480.It Cm deprecated 481(Inet6 only.) 482Set the IPv6 deprecated address bit. 483.It Fl deprecated 484(Inet6 only.) 485Clear the IPv6 deprecated address bit. 486.It Cm tentative 487(Inet6 only.) 488Set the IPv6 tentative address bit. 489.It Fl tentative 490(Inet6 only.) 491Clear the IPv6 tentative address bit. 492.\" see 493.\" Xr eon 5 . 494.\" .It Cm nsellength Ar n 495.\" .Pf ( Tn ISO 496.\" only) 497.\" This specifies a trailing number of bytes for a received 498.\" .Tn NSAP 499.\" used for local identification, the remaining leading part of which is 500.\" taken to be the 501.\" .Tn NET 502.\" (Network Entity Title). 503.\" The default value is 1, which is conformant to US 504.\" .Tn GOSIP . 505.\" When an ISO address is set in an ifconfig command, 506.\" it is really the 507.\" .Tn NSAP 508.\" which is being specified. 509.\" For example, in 510.\" .Tn US GOSIP , 511.\" 20 hex digits should be 512.\" specified in the 513.\" .Tn ISO NSAP 514.\" to be assigned to the interface. 515.\" There is some evidence that a number different from 1 may be useful 516.\" for 517.\" .Tn AFI 518.\" 37 type addresses. 519.It Cm range Ar netrange 520Under appletalk, set the interface to respond to a 521.Ar netrange 522of the form 523.Ar startnet Ns - Ns Ar endnet . 524Appletalk uses this scheme instead of 525netmasks though 526.Dx 527implements it internally as a set of netmasks. 528.It Cm remove 529Another name for the 530.Fl alias 531parameter. 532Introduced for compatibility 533with 534.Bsx . 535.It Cm phase 536The argument following this specifies the version (phase) of the 537Appletalk network attached to the interface. 538Values of 1 or 2 are permitted. 539.Sm off 540.It Cm link Op Cm 0 No - Cm 2 541.Sm on 542Enable special processing of the link level of the interface. 543These three options are interface specific in actual effect, however, 544they are in general used to select special modes of operation. 545An example 546of this is to enable SLIP compression, or to select the connector type 547for some Ethernet cards. 548Refer to the man page for the specific driver 549for more information. 550.Sm off 551.It Fl link Op Cm 0 No - Cm 2 552.Sm on 553Disable special processing at the link level with the specified interface. 554.It Cm compress 555Another name for the 556.Cm link0 557parameter. 558.It Cm normal 559Another name for the 560.Fl link0 561parameter. 562.It Cm noicmp 563Another name for the 564.Cm link1 565parameter. 566.It Cm monitor 567Put the interface in monitor mode. 568No packets are transmitted, and received packets are discarded after 569.Xr bpf 4 570processing. 571.It Fl monitor 572Take the interface out of monitor mode. 573.It Cm up 574Mark an interface 575.Dq up . 576This may be used to enable an interface after an 577.Dq Nm Cm down . 578It happens automatically when setting the first address on an interface. 579If the interface was reset when previously marked down, 580the hardware will be re-initialized. 581.El 582.Pp 583The following parameters are specific to cloning 584IEEE 802.11 wireless interfaces with the 585.Cm create 586request: 587.Bl -tag -width indent 588.It Cm wlandev Ar device 589Use 590.Ar device 591as the parent for the cloned device. 592.It Cm wlanmode Ar mode 593Specify the operating mode for this cloned device. 594.Ar mode 595is one of 596.Cm sta , 597.Cm ahdemo 598(or 599.Cm adhoc-demo ), 600.Cm ibss , 601(or 602.Cm adhoc ), 603.Cm ap , 604(or 605.Cm hostap ), 606.Cm wds , 607.Cm tdma , 608.Cm mesh , 609and 610.Cm monitor . 611The operating mode of a cloned interface cannot be changed. 612The 613.Cm tdma 614mode is actually implemented as an 615.Cm adhoc-demo 616interface with special properties. 617.It Cm wlanbssid Ar bssid 618The 802.11 mac address to use for the bssid. 619This must be specified at create time for a legacy 620.Cm wds 621device. 622.It Cm wlanaddr Ar address 623The local mac address. 624If this is not specified then a mac address will automatically be assigned 625to the cloned device. 626Typically this address is the same as the address of the parent device 627but if the 628.Cm bssid 629parameter is specified then the driver will craft a unique address for 630the device (if supported). 631.It Cm wdslegacy 632Mark a 633.Cm wds 634device as operating in ``legacy mode''. 635Legacy 636.Cm wds 637devices have a fixed peer relationship and do not, for example, roam 638if their peer stops communicating. 639For completeness a Dynamic WDS (DWDS) interface may marked as 640.Fl wdslegacy . 641.It Cm bssid 642Request a unique local mac address for the cloned device. 643This is only possible if the device supports multiple mac addresses. 644To force use of the parent's mac address use 645.Fl bssid . 646.It Cm beacons 647Mark the cloned interface as depending on hardware support to 648track received beacons. 649To have beacons tracked in software use 650.Fl beacons . 651For 652.Cm hostap 653mode 654.Fl beacons 655can also be used to indicate no beacons should 656be transmitted; this can be useful when creating a WDS configuration but 657.Cm wds 658interfaces can only be created as companions to an access point. 659.El 660.Pp 661The following parameters are specific to IEEE 802.11 wireless interfaces 662cloned with a 663.Cm create 664operation: 665.Bl -tag -width indent 666.It Cm ampdu 667Enable sending and receiving AMPDU frames when using 802.11n (default). 668The 802.11n specification states a compliant station must be capable 669of receiving AMPDU frames but transmission is optional. 670Use 671.Fl ampdu 672to disable all use of AMPDU with 802.11n. 673For testing and/or to work around interoperability problems one can use 674.Cm ampdutx 675and 676.Cm ampdurx 677to control use of AMPDU in one direction. 678.It Cm ampdudensity Ar density 679Set the AMPDU density parameter used when operating with 802.11n. 680This parameter controls the inter-packet gap for AMPDU frames. 681The sending device normally controls this setting but a receiving station 682may request wider gaps. 683Legal values for 684.Ar density 685are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds). 686A value of 687.Cm - 688is treated the same as 0. 689.It Cm ampdulimit Ar limit 690Set the limit on packet size for receiving AMPDU frames when operating 691with 802.11n. 692Legal values for 693.Ar limit 694are 8192, 16384, 32768, and 65536 but one can also specify 695just the unique prefix: 8, 16, 32, 64. 696Note the sender may limit the size of AMPDU frames to be less 697than the maximum specified by the receiving station. 698.It Cm amsdu 699Enable sending and receiving AMSDU frames when using 802.11n. 700By default AMSDU is received but not transmitted. 701Use 702.Fl amsdu 703to disable all use of AMSDU with 802.11n. 704For testing and/or to work around interoperability problems one can use 705.Cm amsdutx 706and 707.Cm amsdurx 708to control use of AMSDU in one direction. 709.It Cm amsdulimit Ar limit 710Set the limit on packet size for sending and receiving AMSDU frames 711when operating with 802.11n. 712Legal values for 713.Ar limit 714are 7935 and 3839 (bytes). 715Note the sender may limit the size of AMSDU frames to be less 716than the maximum specified by the receiving station. 717Note also that devices are not required to support the 7935 limit, 718only 3839 is required by the specification and the larger value 719may require more memory to be dedicated to support functionality 720that is rarely used. 721.It Cm apbridge 722When operating as an access point, pass packets between 723wireless clients directly (default). 724To instead let them pass up through the 725system and be forwarded using some other mechanism, use 726.Fl apbridge . 727Disabling the internal bridging 728is useful when traffic is to be processed with 729packet filtering. 730.It Cm authmode Ar mode 731Set the desired authentication mode in infrastructure mode. 732Not all adapters support all modes. 733The set of 734valid modes is 735.Cm none , open , shared 736(shared key), 737.Cm 8021x 738(IEEE 802.1x), 739and 740.Cm wpa 741(IEEE WPA/WPA2/802.11i). 742The 743.Cm 8021x 744and 745.Cm wpa 746modes are only useful when using an authentication service 747(a supplicant for client operation or an authenticator when 748operating as an access point). 749Modes are case insensitive. 750.It Cm bgscan 751Enable background scanning when operating as a station. 752Background scanning is a technique whereby a station associated to 753an access point will temporarily leave the channel to scan for 754neighboring stations. 755This allows a station to maintain a cache of nearby access points 756so that roaming between access points can be done without 757a lengthy scan operation. 758Background scanning is done only when a station is not busy and 759any outbound traffic will cancel a scan operation. 760Background scanning should never cause packets to be lost though 761there may be some small latency if outbound traffic interrupts a 762scan operation. 763By default background scanning is enabled if the device is capable. 764To disable background scanning, use 765.Fl bgscan . 766Background scanning is controlled by the 767.Cm bgscanidle 768and 769.Cm bgscanintvl 770parameters. 771Background scanning must be enabled for roaming; this is an artifact 772of the current implementation and may not be required in the future. 773.It Cm bgscanidle Ar idletime 774Set the minimum time a station must be idle (not transmitting or 775receiving frames) before a background scan is initiated. 776The 777.Ar idletime 778parameter is specified in milliseconds. 779By default a station must be idle at least 250 milliseconds before 780a background scan is initiated. 781The idle time may not be set to less than 100 milliseconds. 782.It Cm bgscanintvl Ar interval 783Set the interval at which background scanning is attempted. 784The 785.Ar interval 786parameter is specified in seconds. 787By default a background scan is considered every 300 seconds (5 minutes). 788The 789.Ar interval 790may not be set to less than 15 seconds. 791.It Cm bintval Ar interval 792Set the interval at which beacon frames are sent when operating in 793ad-hoc or ap mode. 794The 795.Ar interval 796parameter is specified in TU's (1024 usecs). 797By default beacon frames are transmitted every 100 TU's. 798.It Cm bmissthreshold Ar count 799Set the number of consecutive missed beacons at which the station 800will attempt to roam (i.e., search for a new access point). 801The 802.Ar count 803parameter must be in the range 1 to 255; though the 804upper bound may be reduced according to device capabilities. 805The default threshold is 7 consecutive missed beacons; but 806this may be overridden by the device driver. 807Another name for the 808.Cm bmissthreshold 809parameter is 810.Cm bmiss . 811.It Cm bssid Ar address 812Specify the MAC address of the access point to use when operating 813as a station in a BSS network. 814This overrides any automatic selection done by the system. 815To disable a previously selected access point, supply 816.Cm any , none , 817or 818.Cm - 819for the address. 820This option is useful when more than one access point uses the same SSID. 821Another name for the 822.Cm bssid 823parameter is 824.Cm ap . 825.It Cm burst 826Enable packet bursting. 827Packet bursting is a transmission technique whereby the wireless 828medium is acquired once to send multiple frames and the interframe 829spacing is reduced. 830This technique can significantly increase throughput by reducing 831transmission overhead. 832Packet bursting is supported by the 802.11e QoS specification 833and some devices that do not support QoS may still be capable. 834By default packet bursting is enabled if a device is capable 835of doing it. 836To disable packet bursting, use 837.Fl burst . 838.It Cm chanlist Ar channels 839Set the desired channels to use when scanning for access 840points, neighbors in an IBSS network, or looking for unoccupied 841channels when operating as an access point. 842The set of channels is specified as a comma-separated list with 843each element in the list representing either a single channel number or a range 844of the form 845.Dq Li a-b . 846Channel numbers must be in the range 1 to 255 and be permissible 847according to the operating characteristics of the device. 848.It Cm channel Ar number 849Set a single desired channel. 850Channels range from 1 to 255, but the exact selection available 851depends on the region your adaptor was manufactured for. 852Setting 853the channel to 854.Li any , 855or 856.Cm - 857will clear any desired channel and, if the device is marked up, 858force a scan for a channel to operate on. 859Alternatively the frequency, in megahertz, may be specified 860instead of the channel number. 861.Pp 862When there are several ways to use a channel the channel 863number/frequency may be appended with attributes to clarify. 864For example, if a device is capable of operating on channel 6 865with 802.11n and 802.11g then one can specify that g-only use 866should be used by specifying ``6:g''. 867Similarly the channel width can be specified by appending it 868with ``/''; e.g. ``6/40'' specifies a 40MHz wide channel, 869These attributes can be combined as in: ``6:ht/40''. 870The full set of flags specified following a `:'' are: 871.Cm a 872(802.11a), 873.Cm b 874(802.11b), 875.Cm d 876(Atheros Dynamic Turbo mode), 877.Cm g 878(802.11g), 879.Cm h 880or 881.Cm n 882(802.11n aka HT), 883.Cm s 884(Atheros Static Turbo mode), 885and 886.Cm t 887(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt''). 888The full set of channel widths following a '/' are: 889.Cm 5 890(5MHz aka quarter-rate channel), 891.Cm 10 892(10MHz aka half-rate channel), 893.Cm 20 894(20MHz mostly for use in specifying ht20), 895and 896.Cm 40 897(40MHz mostly for use in specifying ht40), 898In addition, 899a 40MHz HT channel specification may include the location 900of the extension channel by appending ``+'' or ``-'' for above and below, 901respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation 902with the center channel at frequency 2437 and the extension channel above. 903.It Cm country Ar name 904Set the country code to use in calculating the regulatory constraints 905for operation. 906In particular the set of available channels, how the wireless device 907will operation on the channels, and the maximum transmit power that 908can be used on a channel are defined by this setting. 909Country/Region codes are specified as a 2-character abbreviation 910defined by ISO 3166 or using a longer, but possibly ambiguous, spelling; 911e.g. "ES" and "Spain". 912The set of country codes are taken from /etc/regdomain.xml and can also 913be viewed with the ``list countries'' request. 914Note that not all devices support changing the country code from a default 915setting; typically stored in EEPROM. 916See also 917.Cm regdomain , 918.Cm indoor , 919.Cm outdoor , 920and 921.Cm anywhere . 922.It Cm dfs 923Enable Dynamic Frequency Selection (DFS) as specified in 802.11h. 924DFS embodies several facilities including detection of overlapping 925radar signals, dynamic transmit power control, and channel selection 926according to a least-congested criteria. 927DFS support is mandatory for some 5Ghz frequencies in certain 928locales (e.g. ETSI). 929By default DFS is enabled according to the regulatory definitions 930specified in /etc/regdomain.xml and the current country code, regdomain, 931and channel. 932Note the underlying device (and driver) must support radar detection 933for full DFS support to work. 934To be fully compliant with the local regulatory agency frequencies that 935require DFS should not be used unless it is fully supported. 936Use 937.Fl dfs 938to disable this functionality for testing. 939.It Cm dotd 940Enable support for the 802.11d specification (default). 941When this support is enabled in station mode, beacon frames that advertise 942a country code different than the currently configured country code will 943cause an event to be dispatched to user applications. 944This event can be used by the station to adopt that country code and 945operate according to the associated regulatory constraints. 946When operating as an access point with 802.11d enabled the beacon and 947probe response frames transmitted will advertise the current regulatory 948domain settings. 949To disable 802.11d use 950.Fl dotd . 951.It Cm doth 952Enable 802.11h support including spectrum management. 953When 802.11h is enabled beacon and probe response frames will have 954the SpectrumMgt bit set in the capabilities field and 955country and power constraint information elements will be present. 956802.11h support also includes handling Channel Switch Announcements (CSA) 957which are a mechanism to coordinate channel changes by an access point. 958By default 802.11h is enabled if the device is capable. 959To disable 802.11h use 960.Fl doth . 961.It Cm deftxkey Ar index 962Set the default key to use for transmission. 963Typically this is only set when using WEP encryption. 964Note that you must set a default transmit key 965for the system to know which key to use in encrypting outbound traffic. 966The 967.Cm weptxkey 968is an alias for this request; it is provided for backwards compatibility. 969.It Cm dtimperiod Ar period 970Set the 971DTIM 972period for transmitting buffered multicast data frames when 973operating in ap mode. 974The 975.Ar period 976specifies the number of beacon intervals between DTIM 977and must be in the range 1 to 15. 978By default DTIM is 1 (i.e., DTIM occurs at each beacon). 979.It Cm dturbo 980Enable the use of Atheros Dynamic Turbo mode when communicating with 981another Dynamic Turbo-capable station. 982Dynamic Turbo mode is an Atheros-specific mechanism by which 983stations switch between normal 802.11 operation and a ``boosted'' 984mode in which a 40MHz wide channel is used for communication. 985Stations using Dynamic Turbo mode operate boosted only when the 986channel is free of non-dturbo stations; when a non-dturbo station 987is identified on the channel all stations will automatically drop 988back to normal operation. 989By default, Dynamic Turbo mode is not enabled, even if the device is capable. 990Note that turbo mode (dynamic or static) is only allowed on some 991channels depending on the regulatory constraints; use the 992.Cm list chan 993command to identify the channels where turbo mode may be used. 994To disable Dynamic Turbo mode use 995.Fl dturbo . 996.It Cm dwds 997Enable Dynamic WDS (DWDS) support. 998DWDS is a facility by which 4-address traffic can be carried between 999stations operating in infrastructure mode. 1000A station first associates to an access point and authenticates using 1001normal procedures (e.g. WPA). 1002Then 4-address frames are passed to carry traffic for stations 1003operating on either side of the wireless link. 1004DWDS extends the normal WDS mechanism by leveraging existing security 1005protocols and eliminating static binding. 1006.Pp 1007When DWDS is enabled on an access point 4-address frames received from 1008an authorized station will generate a ``DWDS discovery'' event to user 1009applications. 1010This event should be used to create a WDS interface that is bound 1011to the remote station (and usually plumbed into a bridge). 1012Once the WDS interface is up and running 4-address traffic then logically 1013flows through that interface. 1014.Pp 1015When DWDS is enabled on a station, traffic with a destination address 1016different from the peer station are encapsulated in a 4-address frame 1017and transmitted to the peer. 1018All 4-address traffic uses the security information of the stations 1019(e.g. cryptographic keys). 1020A station is associated using 802.11n facilities may transport 10214-address traffic using these same mechanisms; this depends on available 1022resources and capabilities of the device. 1023The DWDS implementation guards against layer 2 routing loops of 1024multicast traffic. 1025.It Cm ff 1026Enable the use of Atheros Fast Frames when communicating with 1027another Fast Frames-capable station. 1028Fast Frames are an encapsulation technique by which two 802.3 1029frames are transmitted in a single 802.11 frame. 1030This can noticeably improve throughput but requires that the 1031receiving station understand how to decapsulate the frame. 1032Fast frame use is negotiated using the Atheros 802.11 vendor-specific 1033protocol extension so enabling use is safe when communicating with 1034non-Atheros devices. 1035By default, use of fast frames is enabled if the device is capable. 1036To explicitly disable fast frames, use 1037.Fl ff . 1038.It Cm fragthreshold Ar length 1039Set the threshold for which transmitted frames are broken into fragments. 1040The 1041.Ar length 1042argument is the frame size in bytes and must be in the range 256 to 2346. 1043Setting 1044.Ar length 1045to 1046.Li 2346 , 1047.Cm any , 1048or 1049.Cm - 1050disables transmit fragmentation. 1051Not all adapters honor the fragmentation threshold. 1052.It Cm hidessid 1053When operating as an access point, do not broadcast the SSID 1054in beacon frames or respond to probe request frames unless 1055they are directed to the ap (i.e., they include the ap's SSID). 1056By default, the SSID is included in beacon frames and 1057undirected probe request frames are answered. 1058To re-enable the broadcast of the SSID etc., use 1059.Fl hidessid . 1060.It Cm ht 1061Enable use of High Throughput (HT) when using 802.11n (default). 1062The 802.11n specification includes mechanisms for operation 1063on 20MHz and 40MHz wide channels using different signalling mechanisms 1064than specified in 802.11b, 802.11g, and 802.11a. 1065Stations negotiate use of these facilities, termed HT20 and HT40, 1066when they associate. 1067To disable all use of 802.11n use 1068.Fl ht . 1069To disable use of HT20 (e.g. to force only HT40 use) use 1070.Fl ht20 . 1071To disable use of HT40 use 1072.Fl ht40 . 1073.Pp 1074HT configuration is used to ``auto promote'' operation 1075when several choices are available. 1076For example, if a station associates to an 11n-capable access point 1077it controls whether the station uses legacy operation, HT20, or HT40. 1078When an 11n-capable device is setup as an access point and 1079Auto Channel Selection is used to locate a channel to operate on, 1080HT configuration controls whether legacy, HT20, or HT40 operation is setup 1081on the selected channel. 1082If a fixed channel is specified for a station then HT configuration can 1083be given as part of the channel specification; e.g. 6:ht/20 to setup 1084HT20 operation on channel 6. 1085.It Cm htcompat 1086Enable use of compatibility support for pre-802.11n devices (default). 1087The 802.11n protocol specification went through several incompatible iterations. 1088Some vendors implemented 11n support to older specifications that 1089will not interoperate with a purely 11n-compliant station. 1090In particular the information elements included in management frames 1091for old devices are different. 1092When compatibility support is enabled both standard and compatible data 1093will be provided. 1094Stations that associate using the compatibility mechanisms are flagged 1095in ``list sta''. 1096To disable compatibility support use 1097.Fl htcompat . 1098.It Cm htprotmode Ar technique 1099For interfaces operating in 802.11n, use the specified 1100.Ar technique 1101for protecting HT frames in a mixed legacy/HT network. 1102The set of valid techniques is 1103.Cm off , 1104and 1105.Cm rts 1106(RTS/CTS, default). 1107Technique names are case insensitive. 1108.It Cm inact 1109Enable inactivity processing for stations associated to an 1110access point (default). 1111When operating as an access point the 802.11 layer monitors 1112the activity of each associated station. 1113When a station is inactive for 5 minutes it will send several 1114``probe frames'' to see if the station is still present. 1115If no response is received then the station is deauthenticated. 1116Applications that prefer to handle this work can disable this 1117facility by using 1118.Fl inact . 1119.It Cm indoor 1120Set the location to use in calculating regulatory constraints. 1121The location is also advertised in beacon and probe response frames 1122when 802.11d is enabled with 1123.Cm dotd . 1124See also 1125.Cm outdoor , 1126.Cm anywhere , 1127.Cm country , 1128and 1129.Cm regdomain . 1130.It Cm list active 1131Display the list of channels available for use taking into account 1132any restrictions set with the 1133.Cm chanlist 1134directive. 1135See the description of 1136.Cm list chan 1137for more information. 1138.It Cm list caps 1139Display the adaptor's capabilities, including the operating 1140modes supported. 1141.It Cm list chan 1142Display the list of channels available for use. 1143Channels are shown with their IEEE channel number, equivalent 1144frequency, and usage modes. 1145Channels identified as 1146.Ql 11g 1147are also usable in 1148.Ql 11b 1149mode. 1150Channels identified as 1151.Ql 11a Turbo 1152may be used only for Atheros' Static Turbo mode 1153(specified with 1154.Cm mediaopt turbo ) . 1155Channels marked with a 1156.Ql * 1157have a regulatory constraint that they be passively scanned. 1158This means a station is not permitted to transmit on the channel until 1159it identifies the channel is being used for 802.11 communication; 1160typically by hearing a beacon frame from an access point operating 1161on the channel. 1162.Cm list freq 1163is another way of requesting this information. 1164By default a compacted list of channels is displayed; if the 1165.Fl v 1166option is specified then all channels are shown. 1167.It Cm list countries 1168Display the set of country codes and regulatory domains that can be 1169used in regulatory configuration. 1170.It Cm list mac 1171Display the current MAC Access Control List state. 1172Each address is prefixed with a character that indicates the 1173current policy applied to it: 1174.Ql + 1175indicates the address is allowed access, 1176.Ql - 1177indicates the address is denied access, 1178.Ql * 1179indicates the address is present but the current policy open 1180(so the ACL is not consulted). 1181.It Cm list mesh 1182Displays the mesh routing table, used for forwarding packets on a mesh 1183network. 1184.It Cm list regdomain 1185Display the current regulatory settings including the available channels 1186and transmit power caps. 1187.It Cm list roam 1188Display the parameters that govern roaming operation. 1189.It Cm list txparam 1190Display the parameters that govern transmit operation. 1191.It Cm list txpower 1192Display the transmit power caps for each channel. 1193.It Cm list scan 1194Display the access points and/or ad-hoc neighbors 1195located in the vicinity. 1196This information may be updated automatically by the adapter 1197with a 1198.Cm scan 1199request or through background scanning. 1200Depending on the capabilities of the stations the following 1201flags can be included in the output: 1202.Bl -tag -width 3n 1203.It Li A 1204Authorized. 1205Indicates that the station is permitted to send/receive data frames. 1206.It Li E 1207Extended Rate Phy (ERP). 1208Indicates that the station is operating in an 802.11g network 1209using extended transmit rates. 1210.It Li H 1211High Throughput (HT). 1212Indicates that the station is using HT transmit rates. 1213If a `+' follows immediately after then the station associated 1214using deprecated mechanisms supported only when 1215.Cm htcompat 1216is enabled. 1217.It Li P 1218Power Save. 1219Indicates that the station is operating in power save mode. 1220.It Li Q 1221Quality of Service (QoS). 1222Indicates that the station is using QoS encapsulation for 1223data frame. 1224QoS encapsulation is enabled only when WME mode is enabled. 1225.It Li T 1226Transitional Security Network (TSN). 1227Indicates that the station associated using TSN; see also 1228.Cm tsn 1229below. 1230.It Li W 1231Wi-Fi Protected Setup (WPS). 1232Indicates that the station associated using WPS. 1233.El 1234.Pp 1235By default interesting information elements captured from the neighboring 1236stations are displayed at the end of each row. 1237Possible elements include: 1238.Cm WME 1239(station supports WME), 1240.Cm WPA 1241(station supports WPA), 1242.Cm WPS 1243(station supports WPS), 1244.Cm RSN 1245(station supports 802.11i/RSN), 1246.Cm HTCAP 1247(station supports 802.11n/HT communication), 1248.Cm ATH 1249(station supports Atheros protocol extensions), 1250.Cm VEN 1251(station supports unknown vendor-specific extensions). 1252If the 1253.Fl v 1254flag is used all the information elements and their 1255contents will be shown. 1256Specifying the 1257.Fl v 1258flag also enables display of long SSIDs. 1259The 1260.Cm list ap 1261command is another way of requesting this information. 1262.It Cm list sta 1263When operating as an access point display the stations that are 1264currently associated. 1265When operating in ad-hoc mode display stations identified as 1266neighbors in the IBSS. 1267When operating in mesh mode display stations identified as 1268neighbors in the MBSS. 1269When operating in station mode display the access point. 1270Capabilities advertised by the stations are described under 1271the 1272.Cm scan 1273request. 1274Depending on the capabilities of the stations the following 1275flags can be included in the output: 1276.Bl -tag -width 3n 1277.It Li A 1278Authorized. 1279Indicates that the station is permitted to send/receive data frames. 1280.It Li E 1281Extended Rate Phy (ERP). 1282Indicates that the station is operating in an 802.11g network 1283using extended transmit rates. 1284.It Li H 1285High Throughput (HT). 1286Indicates that the station is using HT transmit rates. 1287If a `+' follows immediately after then the station associated 1288using deprecated mechanisms supported only when 1289.Cm htcompat 1290is enabled. 1291.It Li P 1292Power Save. 1293Indicates that the station is operating in power save mode. 1294.It Li Q 1295Quality of Service (QoS). 1296Indicates that the station is using QoS encapsulation for 1297data frame. 1298QoS encapsulation is enabled only when WME mode is enabled. 1299.It Li T 1300Transitional Security Network (TSN). 1301Indicates that the station associated using TSN; see also 1302.Cm tsn 1303below. 1304.It Li W 1305Wi-Fi Protected Setup (WPS). 1306Indicates that the station associated using WPS. 1307.El 1308.Pp 1309By default information elements received from associated stations 1310are displayed in a short form; the 1311.Fl v 1312flag causes this information to be displayed symbolically. 1313.It Cm list wme 1314Display the current channel parameters to use when operating in WME mode. 1315If the 1316.Fl v 1317option is specified then both channel and BSS parameters are displayed 1318for each AC (first channel, then BSS). 1319When WME mode is enabled for an adaptor this information will be 1320displayed with the regular status; this command is mostly useful 1321for examining parameters when WME mode is disabled. 1322See the description of the 1323.Cm wme 1324directive for information on the various parameters. 1325.It Cm lscan 1326A variant of 1327.Cm scan 1328(see below) that displays long SSIDs. 1329.It Cm maxretry Ar count 1330Set the maximum number of tries to use in sending unicast frames. 1331The default setting is 6 but drivers may override this with a value 1332they choose. 1333.It Cm mcastrate Ar rate 1334Set the rate for transmitting multicast/broadcast frames. 1335Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1336This rate should be valid for the current operating conditions; 1337if an invalid rate is specified drivers are free to choose an 1338appropriate rate. 1339.It Cm mgtrate Ar rate 1340Set the rate for transmitting management and/or control frames. 1341Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1342.It Cm outdoor 1343Set the location to use in calculating regulatory constraints. 1344The location is also advertised in beacon and probe response frames 1345when 802.11d is enabled with 1346.Cm dotd . 1347See also 1348.Cm anywhere , 1349.Cm country , 1350.Cm indoor , 1351and 1352.Cm regdomain . 1353.It Cm powersave 1354Enable powersave operation. 1355When operating as a client, the station will conserve power by 1356periodically turning off the radio and listening for 1357messages from the access point telling it there are packets waiting. 1358The station must then retrieve the packets. 1359Not all devices support power save operation as a client. 1360The 802.11 specification requires that all access points support 1361power save but some drivers do not. 1362Use 1363.Fl powersave 1364to disable powersave operation when operating as a client. 1365.It Cm powersavemode Ar mode 1366Set powersave mode. 1367The set of valid modes is 1368.Cm off 1369(same as 1370.Fl powersave ) , 1371.Cm on 1372(same as 1373.Cm powersave ) , 1374and 1375.Cm cam 1376(same as 1377.Cm powersave ) . 1378.It Cm powersavesleep Ar sleep 1379Set the desired max powersave sleep time in TU's (1024 usecs). 1380By default the max powersave sleep time is 100 TU's. 1381.It Cm protmode Ar technique 1382For interfaces operating in 802.11g, use the specified 1383.Ar technique 1384for protecting OFDM frames in a mixed 11b/11g network. 1385The set of valid techniques is 1386.Cm off , cts 1387(CTS to self), 1388and 1389.Cm rtscts 1390(RTS/CTS). 1391Technique names are case insensitive. 1392Not all devices support 1393.Cm cts 1394as a protection technique. 1395.It Cm pureg 1396When operating as an access point in 802.11g mode allow only 139711g-capable stations to associate (11b-only stations are not 1398permitted to associate). 1399To allow both 11g and 11b-only stations to associate, use 1400.Fl pureg . 1401.It Cm puren 1402When operating as an access point in 802.11n mode allow only 1403HT-capable stations to associate (legacy stations are not 1404permitted to associate). 1405To allow both HT and legacy stations to associate, use 1406.Fl puren . 1407.It Cm regdomain Ar sku 1408Set the regulatory domain to use in calculating the regulatory constraints 1409for operation. 1410In particular the set of available channels, how the wireless device 1411will operation on the channels, and the maximum transmit power that 1412can be used on a channel are defined by this setting. 1413Regdomain codes (SKU's) are taken from /etc/regdomain.xml and can also 1414be viewed with the ``list countries'' request. 1415Note that not all devices support changing the regdomain from a default 1416setting; typically stored in EEPROM. 1417See also 1418.Cm country , 1419.Cm indoor , 1420.Cm outdoor , 1421and 1422.Cm anywhere . 1423.It Cm rifs 1424Enable use of Reduced InterFrame Spacing (RIFS) when operating in 802.11n 1425on an HT channel. 1426Note that RIFS must be supported by both the station and access point 1427for it to be used. 1428To disable RIFS use 1429.Fl rifs . 1430.It Cm roam:rate Ar rate 1431Set the threshold for controlling roaming when operating in a BSS. 1432The 1433.Ar rate 1434parameter specifies the transmit rate in megabits 1435at which roaming should be considered. 1436If the current transmit rate 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 rate threshold; the default values are: 144512 Mb/s (11a), 2 Mb/s (11b), 2 Mb/s (11g), MCS 1 (11na, 11ng). 1446.It Cm roam:rssi Ar rssi 1447Set the threshold for controlling roaming when operating in a BSS. 1448The 1449.Ar rssi 1450parameter specifies the receive signal strength in dBm units 1451at which roaming should be considered. 1452If the current rssi drops below this setting and background scanning 1453is enabled, then the system will check if a more desirable access point is 1454available and switch over to it. 1455The current scan cache contents are used if they are considered 1456valid according to the 1457.Cm scanvalid 1458parameter; otherwise a background scan operation is triggered before 1459any selection occurs. 1460Each channel type has a separate rssi threshold; the default values are 1461all 7 dBm. 1462.It Cm roaming Ar mode 1463When operating as a station, control how the system will 1464behave when communication with the current access point 1465is broken. 1466The 1467.Ar mode 1468argument may be one of 1469.Cm device 1470(leave it to the hardware device to decide), 1471.Cm auto 1472(handle either in the device or the operating system\[em]as appropriate), 1473.Cm manual 1474(do nothing until explicitly instructed). 1475By default, the device is left to handle this if it is 1476capable; otherwise, the operating system will automatically 1477attempt to reestablish communication. 1478Manual mode is used by applications such as 1479.Xr wpa_supplicant 8 1480that want to control the selection of an access point. 1481.It Cm rtsthreshold Ar length 1482Set the threshold for which 1483transmitted frames are preceded by transmission of an 1484RTS 1485control frame. 1486The 1487.Ar length 1488argument 1489is the frame size in bytes and must be in the range 1 to 2346. 1490Setting 1491.Ar length 1492to 1493.Li 2346 , 1494.Cm any , 1495or 1496.Cm - 1497disables transmission of RTS frames. 1498Not all adapters support setting the RTS threshold. 1499.It Cm scan 1500Initiate a scan of neighboring stations, wait for it to complete, and 1501display all stations found. 1502Only the super-user can initiate a scan. 1503See 1504.Cm list scan 1505for information on the display. 1506By default a background scan is done; otherwise a foreground 1507scan is done and the station may roam to a different access point. 1508The 1509.Cm list scan 1510request can be used to show recent scan results without 1511initiating a new scan. 1512.It Cm scanvalid Ar threshold 1513Set the maximum time the scan cache contents are considered valid; 1514i.e. will be used without first triggering a scan operation to 1515refresh the data. 1516The 1517.Ar threshold 1518parameter is specified in seconds and defaults to 60 seconds. 1519The minimum setting for 1520.Ar threshold 1521is 10 seconds. 1522One should take care setting this threshold; if it is set too low 1523then attempts to roam to another access point may trigger unnecessary 1524background scan operations. 1525.It Cm shortgi 1526Enable use of Short Guard Interval when operating in 802.11n 1527on an HT channel. 1528NB: this currently enables Short GI on both HT40 and HT20 channels. 1529To disable Short GI use 1530.Fl shortgi . 1531.It Cm smps 1532Enable use of Static Spatial Multiplexing Power Save (SMPS) 1533when operating in 802.11n. 1534A station operating with Static SMPS maintains only a single 1535receive chain active (this can significantly reduce power consumption). 1536To disable SMPS use 1537.Fl smps . 1538.It Cm smpsdyn 1539Enable use of Dynamic Spatial Multiplexing Power Save (SMPS) 1540when operating in 802.11n. 1541A station operating with Dynamic SMPS maintains only a single 1542receive chain active but switches to multiple receive chains when it 1543receives an RTS frame (this can significantly reduce power consumption). 1544Note that stations cannot distinguish between RTS/CTS intended to 1545enable multiple receive chains and those used for other purposes. 1546To disable SMPS use 1547.Fl smps . 1548.It Cm ssid Ar ssid 1549Set the desired Service Set Identifier (aka network name). 1550The SSID is a string up to 32 characters 1551in length and may be specified as either a normal string or in 1552hexadecimal when preceded by 1553.Ql 0x . 1554Additionally, the SSID may be cleared by setting it to 1555.Ql - . 1556.It Cm tdmaslot Ar slot 1557When operating with TDMA, use the specified 1558.Ar slot 1559configuration. 1560The 1561.Ar slot 1562is a number between 0 and the maximum number of slots in the BSS. 1563Note that a station configured as slot 0 is a master and 1564will broadcast beacon frames advertising the BSS; 1565stations configured to use other slots will always 1566scan to locate a master before they ever transmit. 1567By default 1568.Cm tdmaslot 1569is set to 1. 1570.It Cm tdmaslotcnt Ar cnt 1571When operating with TDMA, setup a BSS with 1572.Ar cnt 1573slots. 1574The slot count may be at most 8. 1575The current implementation is only tested with two stations 1576(i.e. point to point applications). 1577This setting is only meaningful when a station is configured as slot 0; 1578other stations adopt this setting from the BSS they join. 1579By default 1580.Cm tdmaslotcnt 1581is set to 2. 1582.It Cm tdmaslotlen Ar len 1583When operating with TDMA, setup a BSS such that each station has a slot 1584.Ar len 1585microseconds long. 1586The slot length must be at least 150 microseconds (1/8 TU) 1587and no more than 65 milliseconds. 1588Note that setting too small a slot length may result in poor channel 1589bandwidth utilization due to factors such as timer granularity and 1590guard time. 1591This setting is only meaningful when a station is configured as slot 0; 1592other stations adopt this setting from the BSS they join. 1593By default 1594.Cm tdmaslotlen 1595is set to 10 milliseconds. 1596.It Cm tdmabintval Ar intval 1597When operating with TDMA, setup a BSS such that beacons are transmitted every 1598.Ar intval 1599superframes to synchronize the TDMA slot timing. 1600A superframe is defined as the number of slots times the slot length; e.g. 1601a BSS with two slots of 10 milliseconds has a 20 millisecond superframe. 1602The beacon interval may not be zero. 1603A lower setting of 1604.Cm tdmabintval 1605causes the timers to be resynchronized more often; this can be help if 1606significant timer drift is observed. 1607By default 1608.Cm tdmabintval 1609is set to 5. 1610.It Cm tsn 1611When operating as an access point with WPA/802.11i allow legacy 1612stations to associate using static key WEP and open authentication. 1613To disallow legacy station use of WEP, use 1614.Fl tsn . 1615.It Cm txpower Ar power 1616Set the power used to transmit frames. 1617The 1618.Ar power 1619argument is specified in .5 dBm units. 1620Out of range values are truncated. 1621Typically only a few discreet power settings are available and 1622the driver will use the setting closest to the specified value. 1623Not all adapters support changing the transmit power. 1624.It Cm ucastrate Ar rate 1625Set a fixed rate for transmitting unicast frames. 1626Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s. 1627This rate should be valid for the current operating conditions; 1628if an invalid rate is specified drivers are free to choose an 1629appropriate rate. 1630.It Cm wepmode Ar mode 1631Set the desired WEP mode. 1632Not all adapters support all modes. 1633The set of valid modes is 1634.Cm off , on , 1635and 1636.Cm mixed . 1637The 1638.Cm mixed 1639mode explicitly tells the adaptor to allow association with access 1640points which allow both encrypted and unencrypted traffic. 1641On these adapters, 1642.Cm on 1643means that the access point must only allow encrypted connections. 1644On other adapters, 1645.Cm on 1646is generally another name for 1647.Cm mixed . 1648Modes are case insensitive. 1649.It Cm weptxkey Ar index 1650Set the WEP key to be used for transmission. 1651This is the same as setting the default transmission key with 1652.Cm deftxkey . 1653.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 1654Set the selected WEP key. 1655If an 1656.Ar index 1657is not given, key 1 is set. 1658A WEP key will be either 5 or 13 1659characters (40 or 104 bits) depending on the local network and the 1660capabilities of the adaptor. 1661It may be specified either as a plain 1662string or as a string of hexadecimal digits preceded by 1663.Ql 0x . 1664For maximum portability, hex keys are recommended; 1665the mapping of text keys to WEP encryption is usually driver-specific. 1666In particular, the 1667.Tn Windows 1668drivers do this mapping differently to 1669.Fx . 1670A key may be cleared by setting it to 1671.Ql - . 1672If WEP is supported then there are at least four keys. 1673Some adapters support more than four keys. 1674If that is the case, then the first four keys 1675(1-4) will be the standard temporary keys and any others will be adaptor 1676specific keys such as permanent keys stored in NVRAM. 1677.Pp 1678Note that you must set a default transmit key with 1679.Cm deftxkey 1680for the system to know which key to use in encrypting outbound traffic. 1681.It Cm wme 1682Enable Wireless Multimedia Extensions (WME) support, if available, 1683for the specified interface. 1684WME is a subset of the IEEE 802.11e standard to support the 1685efficient communication of realtime and multimedia data. 1686To disable WME support, use 1687.Fl wme . 1688Another name for this parameter is 1689.Cm wmm . 1690.Pp 1691The following parameters are meaningful only when WME support is in use. 1692Parameters are specified per-AC (Access Category) and 1693split into those that are used by a station when acting 1694as an access point and those for client stations in the BSS. 1695The latter are received from the access point and may not be changed 1696(at the station). 1697The following Access Categories are recognized: 1698.Pp 1699.Bl -tag -width ".Cm AC_BK" -compact 1700.It Cm AC_BE 1701(or 1702.Cm BE ) 1703best effort delivery, 1704.It Cm AC_BK 1705(or 1706.Cm BK ) 1707background traffic, 1708.It Cm AC_VI 1709(or 1710.Cm VI ) 1711video traffic, 1712.It Cm AC_VO 1713(or 1714.Cm VO ) 1715voice traffic. 1716.El 1717.Pp 1718AC parameters are case-insensitive. 1719Traffic classification is done in the operating system using the 1720vlan priority associated with data frames or the 1721ToS (Type of Service) indication in IP-encapsulated frames. 1722If neither information is present, traffic is assigned to the 1723Best Effort (BE) category. 1724.Bl -tag -width indent 1725.It Cm ack Ar ac 1726Set the ACK policy for QoS transmissions by the local station; 1727this controls whether or not data frames transmitted by a station 1728require an ACK response from the receiving station. 1729To disable waiting for an ACK use 1730.Fl ack . 1731This parameter is applied only to the local station. 1732.It Cm acm Ar ac 1733Enable the Admission Control Mandatory (ACM) mechanism 1734for transmissions by the local station. 1735To disable the ACM use 1736.Fl acm . 1737On stations in a BSS this parameter is read-only and indicates 1738the setting received from the access point. 1739NB: ACM is not supported right now. 1740.It Cm aifs Ar ac Ar count 1741Set the Arbitration Inter Frame Spacing (AIFS) 1742channel access parameter to use for transmissions 1743by the local station. 1744On stations in a BSS this parameter is read-only and indicates 1745the setting received from the access point. 1746.It Cm cwmin Ar ac Ar count 1747Set the CWmin channel access parameter to use for transmissions 1748by the local station. 1749On stations in a BSS this parameter is read-only and indicates 1750the setting received from the access point. 1751.It Cm cwmax Ar ac Ar count 1752Set the CWmax channel access parameter to use for transmissions 1753by the local station. 1754On stations in a BSS this parameter is read-only and indicates 1755the setting received from the access point. 1756.It Cm txoplimit Ar ac Ar limit 1757Set the Transmission Opportunity Limit channel access parameter 1758to use for transmissions by the local station. 1759This parameter defines an interval of time when a WME station 1760has the right to initiate transmissions onto the wireless medium. 1761On stations in a BSS this parameter is read-only and indicates 1762the setting received from the access point. 1763.It Cm bss:aifs Ar ac Ar count 1764Set the AIFS channel access parameter to send to stations in a BSS. 1765This parameter is meaningful only when operating in ap mode. 1766.It Cm bss:cwmin Ar ac Ar count 1767Set the CWmin channel access parameter to send to stations in a BSS. 1768This parameter is meaningful only when operating in ap mode. 1769.It Cm bss:cwmax Ar ac Ar count 1770Set the CWmax channel access parameter to send to stations in a BSS. 1771This parameter is meaningful only when operating in ap mode. 1772.It Cm bss:txoplimit Ar ac Ar limit 1773Set the TxOpLimit channel access parameter to send to stations in a BSS. 1774This parameter is meaningful only when operating in ap mode. 1775.El 1776.It Cm wps 1777Enable Wireless Privacy Subscriber support. 1778Note that WPS support requires a WPS-capable supplicant. 1779To disable this function use 1780.Fl wps . 1781.El 1782.Pp 1783The following parameters support an optional access control list 1784feature available with some adapters when operating in ap mode; see 1785.Xr wlan_acl 4 . 1786This facility allows an access point to accept/deny association 1787requests based on the MAC address of the station. 1788Note that this feature does not significantly enhance security 1789as MAC address spoofing is easy to do. 1790.Bl -tag -width indent 1791.It Cm mac:add Ar address 1792Add the specified MAC address to the database. 1793Depending on the policy setting association requests from the 1794specified station will be allowed or denied. 1795.It Cm mac:allow 1796Set the ACL policy to permit association only by 1797stations registered in the database. 1798.It Cm mac:del Ar address 1799Delete the specified MAC address from the database. 1800.It Cm mac:deny 1801Set the ACL policy to deny association only by 1802stations registered in the database. 1803.It Cm mac:kick Ar address 1804Force the specified station to be deauthenticated. 1805This typically is done to block a station after updating the 1806address database. 1807.It Cm mac:open 1808Set the ACL policy to allow all stations to associate. 1809.It Cm mac:flush 1810Delete all entries in the database. 1811.It Cm mac:radius 1812Set the ACL policy to permit association only by 1813stations approved by a RADIUS server. 1814Note that this feature requires the 1815.Xr hostapd 8 1816program be configured to do the right thing 1817as it handles the RADIUS processing 1818(and marks stations as authorized). 1819.El 1820.Pp 1821The following parameters are related to a wireless interface operating in mesh 1822mode: 1823.Bl -tag -width indent 1824.It Cm meshid Ar meshid 1825Set the desired Mesh Identifier. 1826The Mesh ID is a string up to 32 characters in length. 1827A mesh interface must have a Mesh Identifier specified 1828to reach an operational state. 1829.It Cm meshttl Ar ttl 1830Set the desired ``time to live'' for mesh forwarded packets; 1831this is the number of hops a packet may be forwarded before 1832it is discarded. 1833The default setting for 1834.Cm meshttl 1835is 31. 1836.It Cm meshpeering 1837Enable or disable peering with neighbor mesh stations. 1838Stations must peer before any data packets can be exchanged. 1839By default 1840.Cm meshpeering 1841is enabled. 1842.It Cm meshforward 1843Enable or disable forwarding packets by a mesh interface. 1844By default 1845.Cm meshforward 1846is enabled. 1847.It Cm meshmetric Ar protocol 1848Set the specified 1849.Ar protocol 1850as the link metric protocol used on a mesh network. 1851The default protocol is called 1852.Ar AIRTIME . 1853The mesh interface will restart after changing this setting. 1854.It Cm meshpath Ar protocol 1855Set the specified 1856.Ar protocol 1857as the path selection protocol used on a mesh network. 1858The only available protocol at the moment is called 1859.Ar HWMP 1860(Hybrid Wireless Mesh Protocol). 1861The mesh interface will restart after changing this setting. 1862.It Cm hwmprootmode Ar mode 1863Stations on a mesh network can operate as ``root nodes.'' 1864Root nodes try to find paths to all mesh nodes and advertise themselves 1865regularly. 1866When there is a root mesh node on a network, other mesh nodes can setup 1867paths between themselves faster because they can use the root node 1868to find the destination. 1869This path may not be the best, but on-demand 1870routing will eventually find the best path. 1871The following modes are recognized: 1872.Pp 1873.Bl -tag -width ".Cm PROACTIVE" -compact 1874.It Cm DISABLED 1875Disable root mode. 1876.It Cm NORMAL 1877Send broadcast path requests every two seconds. 1878Nodes on the mesh without a path to this root mesh station with try to 1879discover a path to us. 1880.It Cm PROACTIVE 1881Send broadcast path requests every two seconds and every node must reply 1882with a path reply even if it already has a path to this root mesh station, 1883.It Cm RANN 1884Send broadcast root announcement (RANN) frames. 1885Nodes on the mesh without a path to this root mesh station with try to 1886discover a path to us. 1887.El 1888By default 1889.Cm hwmprootmode 1890is set to 1891.Ar DISABLED . 1892.It Cm hwmpmaxhops Ar cnt 1893Set the maximum number of hops allowed in an HMWP path to 1894.Ar cnt . 1895The default setting for 1896.Cm hwmpmaxhops 1897is 31. 1898.El 1899.Pp 1900The following parameters are for compatibility with other systems: 1901.Bl -tag -width indent 1902.It Cm nwid Ar ssid 1903Another name for the 1904.Cm ssid 1905parameter. 1906Included for 1907.Nx 1908compatibility. 1909.It Cm stationname Ar name 1910Set the name of this station. 1911The station name is not part of the IEEE 802.11 1912protocol though some interfaces support it. 1913As such it only 1914seems to be meaningful to identical or virtually identical equipment. 1915Setting the station name is identical in syntax to setting the SSID. 1916One can also use 1917.Cm station 1918for 1919.Bsx 1920compatibility. 1921.It Cm wep 1922Another way of saying 1923.Cm wepmode on . 1924Included for 1925.Bsx 1926compatibility. 1927.It Fl wep 1928Another way of saying 1929.Cm wepmode off . 1930Included for 1931.Bsx 1932compatibility. 1933.It Cm nwkey key 1934Another way of saying: 1935.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 1936Included for 1937.Nx 1938compatibility. 1939.It Cm nwkey Xo 1940.Sm off 1941.Ar n : k1 , k2 , k3 , k4 1942.Sm on 1943.Xc 1944Another way of saying 1945.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 1946Included for 1947.Nx 1948compatibility. 1949.It Fl nwkey 1950Another way of saying 1951.Cm wepmode off . 1952Included for 1953.Nx 1954compatibility. 1955.El 1956.Pp 1957The following parameters are specific to bridge interfaces: 1958.Bl -tag -width indent 1959.It Cm addm Ar interface 1960Add the interface named by 1961.Ar interface 1962as a member of the bridge. 1963The interface is put into promiscuous mode 1964so that it can receive every packet sent on the network. 1965.It Cm deletem Ar interface 1966Remove the interface named by 1967.Ar interface 1968from the bridge. 1969Promiscuous mode is disabled on the interface when 1970it is removed from the bridge. 1971.It Cm maxaddr Ar size 1972Set the size of the bridge address cache to 1973.Ar size . 1974The default is 100 entries. 1975.It Cm timeout Ar seconds 1976Set the timeout of address cache entries to 1977.Ar seconds 1978seconds. 1979If 1980.Ar seconds 1981is zero, then address cache entries will not be expired. 1982The default is 1200 seconds. 1983.It Cm addr 1984Display the addresses that have been learned by the bridge. 1985.It Cm static Ar interface-name Ar address 1986Add a static entry into the address cache pointing to 1987.Ar interface-name . 1988Static entries are never aged out of the cache or re-placed, even if the 1989address is seen on a different interface. 1990.It Cm deladdr Ar address 1991Delete 1992.Ar address 1993from the address cache. 1994.It Cm flush 1995Delete all dynamically-learned addresses from the address cache. 1996.It Cm flushall 1997Delete all addresses, including static addresses, from the address cache. 1998.It Cm discover Ar interface 1999Mark an interface as a 2000.Dq discovering 2001interface. 2002When the bridge has no address cache entry 2003(either dynamic or static) 2004for the destination address of a packet, 2005the bridge will forward the packet to all 2006member interfaces marked as 2007.Dq discovering . 2008This is the default for all interfaces added to a bridge. 2009.It Fl discover Ar interface 2010Clear the 2011.Dq discovering 2012attribute on a member interface. 2013For packets without the 2014.Dq discovering 2015attribute, the only packets forwarded on the interface are broadcast 2016or multicast packets and packets for which the destination address 2017is known to be on the interface's segment. 2018.It Cm learn Ar interface 2019Mark an interface as a 2020.Dq learning 2021interface. 2022When a packet arrives on such an interface, the source 2023address of the packet is entered into the address cache as being a 2024destination address on the interface's segment. 2025This is the default for all interfaces added to a bridge. 2026.It Fl learn Ar interface 2027Clear the 2028.Dq learning 2029attribute on a member interface. 2030.It Cm span Ar interface 2031Add the interface named by 2032.Ar interface 2033as a span port on the bridge. 2034Span ports transmit a copy of every frame received by the bridge. 2035This is most useful for snooping a bridged network passively on 2036another host connected to one of the span ports of the bridge. 2037.It Fl span Ar interface 2038Delete the interface named by 2039.Ar interface 2040from the list of span ports of the bridge. 2041.It Cm stp Ar interface 2042Enable Spanning Tree protocol on 2043.Ar interface . 2044The 2045.Xr bridge 4 2046driver has support for the IEEE 802.1D Spanning Tree protocol (STP). 2047Spanning Tree is used to detect and remove loops in a network topology. 2048.It Fl stp Ar interface 2049Disable Spanning Tree protocol on 2050.Ar interface . 2051This is the default for all interfaces added to a bridge. 2052.It Cm maxage Ar seconds 2053Set the time that a Spanning Tree protocol configuration is valid. 2054The default is 20 seconds. 2055The minimum is 1 second and the maximum is 255 seconds. 2056.It Cm fwddelay Ar seconds 2057Set the time that must pass before an interface begins forwarding 2058packets when Spanning Tree is enabled. 2059The default is 15 seconds. 2060The minimum is 1 second and the maximum is 255 seconds. 2061.It Cm hellotime Ar seconds 2062Set the time between broadcasting of Spanning Tree protocol 2063configuration messages. 2064The default is 2 seconds. 2065The minimum is 1 second and the maximum is 255 seconds. 2066.It Cm priority Ar value 2067Set the bridge priority for Spanning Tree. 2068The default is 32768. 2069The minimum is 0 and the maximum is 65536. 2070.It Cm ifpriority Ar interface Ar value 2071Set the Spanning Tree priority of 2072.Ar interface 2073to 2074.Ar value . 2075The default is 128. 2076The minimum is 0 and the maximum is 255. 2077.Pp 2078The priority is used to select which interface out of all 2079forwarding and bonded interfaces with the same MAC 2080to output a packet on whe 2081.Cm link2 2082mode is not being used. 2083Note that interfaces in the 'blocking' state do not participate 2084in the priority selection. 2085If the priorities are the same on a non-bonded member, the 2086designated member will be used. 2087.It Cm ifpathcost Ar interface Ar value 2088Set the Spanning Tree path cost of 2089.Ar interface 2090to 2091.Ar value . 2092The default is 55. 2093The minimum is 0 and the maximum is 65535. 2094.Pp 2095The path cost is added to both incoming and outgoing packets on the 2096member, lower values will make the member more valuable. 2097.It Cm ifbondweight Ar interface Ar value 2098Set the number of packets to output on a bonded member before 2099round-robining to the next member. 2100The default is 1. 2101Larger values or different values for each member can be used 2102if bursting would be beneficial or if the outgoing bandwidth 2103on each of the members is asymmetric. 2104For example, one specify a value of 6 on tap0 and 4 on tap1 2105for a 6:4 ratio. 2106Remember that this also controls packet bursting. 2107.It Cm link0 2108The link0 option enables transparent bridging mode. 2109The bridge will make every effort to retain the ethernet header 2110when forwarding packets between interfaces, making the bridging 2111function work more like a hardware bridge device. 2112.It Cm link1 2113The link1 option enables keepalive transmission and automatically 2114places a member into a special blocked mode if no keepalive reception 2115occurs. 2116If either sides of the link uses this option then both sides must use 2117this option. 2118This option is impemented by sending CFG updates on the hello interval 2119to the remote. 2120The link is considered lost after 10 intervals (typically 20 seconds). 2121.It Cm link2 2122The link2 option enables channel bonding (see also ifbondweight). 2123All member interfaces with the same mac address are considered to 2124be in a bonding group. 2125When something like 2126.Xr tap 4 2127is used, you can manually control or copy the mac to create bonding groups. 2128When interface bonding is enabled normally blocked interfaces belonging 2129to the same bonding group as an active forwarding interface will be 2130changed to the bonding state. 2131Both sides of link the member represents must operate in bonding mode 2132for this to work, otherwise the remote end may decide to throw away 2133half your packets. 2134.El 2135.Pp 2136The following parameters are specific to IP tunnel interfaces, 2137.Xr gif 4 : 2138.Bl -tag -width indent 2139.It Cm tunnel Ar src_addr dest_addr 2140Configure the physical source and destination address for IP tunnel 2141interfaces. 2142The arguments 2143.Ar src_addr 2144and 2145.Ar dest_addr 2146are interpreted as the outer source/destination for the encapsulating 2147IPv4/IPv6 header. 2148.It Fl tunnel 2149Unconfigure the physical source and destination address for IP tunnel 2150interfaces previously configured with 2151.Cm tunnel . 2152.It Cm deletetunnel 2153Another name for the 2154.Fl tunnel 2155parameter. 2156.El 2157.Pp 2158The following parameters are specific to 2159.Xr vlan 4 2160interfaces: 2161.Bl -tag -width indent 2162.It Cm vlan Ar vlan_tag 2163Set the VLAN tag value to 2164.Ar vlan_tag . 2165This value is a 16-bit number which is used to create an 802.1Q 2166VLAN header for packets sent from the 2167.Xr vlan 4 2168interface. 2169Note that 2170.Cm vlan 2171and 2172.Cm vlandev 2173must both be set at the same time. 2174.It Cm vlandev Ar iface 2175Associate the physical interface 2176.Ar iface 2177with a 2178.Xr vlan 4 2179interface. 2180Packets transmitted through the 2181.Xr vlan 4 2182interface will be 2183diverted to the specified physical interface 2184.Ar iface 2185with 802.1Q VLAN encapsulation. 2186Packets with 802.1Q encapsulation received 2187by the parent interface with the correct VLAN tag will be diverted to 2188the associated 2189.Xr vlan 4 2190pseudo-interface. 2191The 2192.Xr vlan 4 2193interface is assigned a 2194copy of the parent interface's flags and the parent's ethernet address. 2195The 2196.Cm vlandev 2197and 2198.Cm vlan 2199must both be set at the same time. 2200If the 2201.Xr vlan 4 2202interface already has 2203a physical interface associated with it, this command will fail. 2204To 2205change the association to another physical interface, the existing 2206association must be cleared first. 2207.Pp 2208Note: if the hardware tagging capability 2209is set on the parent interface, the 2210.Xr vlan 4 2211pseudo 2212interface's behavior changes: 2213the 2214.Xr vlan 4 2215interface recognizes that the 2216parent interface supports insertion and extraction of VLAN tags on its 2217own (usually in firmware) and that it should pass packets to and from 2218the parent unaltered. 2219.It Fl vlandev Op Ar iface 2220If the driver is a 2221.Xr vlan 4 2222pseudo device, disassociate the parent interface from it. 2223This breaks the link between the 2224.Xr vlan 4 2225interface and its parent, 2226clears its VLAN tag, flags and its link address and shuts the interface down. 2227The 2228.Ar iface 2229argument is useless and hence deprecated. 2230.El 2231.Pp 2232The following parameters are specific to 2233.Xr carp 4 2234interfaces: 2235.Bl -tag -width indent 2236.It Cm advbase Ar seconds 2237Specifies the base of the advertisement interval in seconds. 2238The acceptable values are 1 to 255. 2239The default value is 1. 2240.\" The default value is 2241.\" .Dv CARP_DFLTINTV . 2242.It Cm advskew Ar interval 2243Specifies the skew to add to the base advertisement interval to 2244make one host advertise slower than another host. 2245It is specified in 1/256 of seconds. 2246The acceptable values are 1 to 254. 2247The default value is 0. 2248.It Cm pass Ar phrase 2249Set the authentication key to 2250.Ar phrase . 2251.It Cm vhid Ar n 2252Set the virtual host ID. 2253This is a required setting. 2254Acceptable values are 1 to 255. 2255.El 2256.Pp 2257The 2258.Nm 2259utility displays the current configuration for a network interface 2260when no optional parameters are supplied. 2261If a protocol family is specified, 2262.Nm 2263will report only the details specific to that protocol family. 2264.Pp 2265If the 2266.Fl m 2267flag is passed before an interface name, 2268.Nm 2269will display the capability list, 2270the maximum amount of data 2271that TCP segmentation offloading is allowed to aggregate and 2272all of the supported media for the specified interface. 2273If 2274.Fl L 2275flag is supplied, address lifetime is displayed for IPv6 addresses, 2276as time offset string. 2277.Pp 2278Optionally, the 2279.Fl a 2280flag may be used instead of an interface name. 2281This flag instructs 2282.Nm 2283to display information about all interfaces in the system. 2284The 2285.Fl d 2286flag limits this to interfaces that are down, and 2287.Fl u 2288limits this to interfaces that are up. 2289When no arguments are given, 2290.Fl a 2291is implied. 2292.Pp 2293The 2294.Fl l 2295flag may be used to list all available interfaces on the system, with 2296no other additional information. 2297Use of this flag is mutually exclusive 2298with all other flags and commands, except for 2299.Fl d 2300(only list interfaces that are down) 2301and 2302.Fl u 2303(only list interfaces that are up). 2304.Pp 2305The 2306.Fl v 2307flag may be used to get more verbose status for an interface. 2308.Pp 2309The 2310.Fl C 2311flag may be used to list all of the interface cloners available on 2312the system, with no additional information. 2313Use of this flag is mutually exclusive with all other flags and commands. 2314.Pp 2315The 2316.Fl k 2317flag causes keying information for the interface, if available, to be 2318printed. 2319For example, the values of 802.11 WEP keys will be printed, if accessible to 2320the current user. 2321This information is not printed by default, as it may be considered 2322sensitive. 2323.Pp 2324If the network interface driver is not present in the kernel then 2325.Nm 2326will attempt to load it. 2327The 2328.Fl n 2329flag disables this behavior. 2330.Pp 2331Only the super-user may modify the configuration of a network interface. 2332.Sh DIAGNOSTICS 2333Messages indicating the specified interface does not exist, the 2334requested address is unknown, or the user is not privileged and 2335tried to alter an interface's configuration. 2336.Sh SEE ALSO 2337.Xr netstat 1 , 2338.Xr carp 4 , 2339.Xr ifmedia 4 , 2340.Xr netintro 4 , 2341.Xr polling 4 , 2342.Xr vlan 4 , 2343.\" .Xr eon 5 , 2344.Xr rc 8 , 2345.Xr routed 8 , 2346.Xr sysctl 8 2347.Sh HISTORY 2348The 2349.Nm 2350utility appeared in 2351.Bx 4.2 . 2352.Sh BUGS 2353Basic IPv6 node operation requires a link-local address on each 2354interface configured for IPv6. 2355Normally, such an address is automatically configured by the 2356kernel on each interface added to the system; this behaviour may 2357be disabled by setting the sysctl MIB variable 2358.Va net.inet6.ip6.auto_linklocal 2359to 0. 2360.Pp 2361If you delete such an address using 2362.Nm , 2363the kernel may act very odd. 2364Do this at your own risk. 2365