xref: /freebsd/sbin/ifconfig/ifconfig.8 (revision 8847579c57d6aff2b3371c707dce7a2cee8389aa)
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28.\"     From: @(#)ifconfig.8	8.3 (Berkeley) 1/5/94
29.\" $FreeBSD$
30.\"
31.Dd June 23, 2006
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.Nm
75.Op Fl g Ar groupname
76.Sh DESCRIPTION
77The
78.Nm
79utility is used to assign an address
80to a network interface and/or configure
81network interface parameters.
82The
83.Nm
84utility must be used at boot time to define the network address
85of each interface present on a machine; it may also be used at
86a later time to redefine an interface's address
87or other operating parameters.
88.Pp
89The following options are available:
90.Bl -tag -width indent
91.It Ar address
92For the
93.Tn DARPA Ns -Internet
94family,
95the address is either a host name present in the host name data
96base,
97.Xr hosts 5 ,
98or a
99.Tn DARPA
100Internet address expressed in the Internet standard
101.Dq dot notation .
102.Pp
103It is also possible to use the CIDR notation (also known as the
104slash notation) to include the netmask.
105That is, one can specify an address like
106.Li 192.168.0.1/16 .
107.Pp
108For
109.Dq inet6
110family, it is also possible to specify the prefix length using the slash
111notation, like
112.Li ::1/128 .
113See the
114.Cm prefixlen
115parameter below for more information.
116.\" For the Xerox Network Systems(tm) family,
117.\" addresses are
118.\" .Ar net:a.b.c.d.e.f ,
119.\" where
120.\" .Ar net
121.\" is the assigned network number (in decimal),
122.\" and each of the six bytes of the host number,
123.\" .Ar a
124.\" through
125.\" .Ar f ,
126.\" are specified in hexadecimal.
127.\" The host number may be omitted on IEEE 802 protocol
128.\" (Ethernet, FDDI, and Token Ring) interfaces,
129.\" which use the hardware physical address,
130.\" and on interfaces other than the first.
131.\" For the
132.\" .Tn ISO
133.\" family, addresses are specified as a long hexadecimal string,
134.\" as in the Xerox family.
135.\" However, two consecutive dots imply a zero
136.\" byte, and the dots are optional, if the user wishes to (carefully)
137.\" count out long strings of digits in network byte order.
138.Pp
139The link-level
140.Pq Dq link
141address
142is specified as a series of colon-separated hex digits.
143This can be used to
144e.g.\& set a new MAC address on an ethernet interface, though the
145mechanism used is not ethernet-specific.
146If the interface is already
147up when this option is used, it will be briefly brought down and
148then brought back up again in order to ensure that the receive
149filter in the underlying ethernet hardware is properly reprogrammed.
150.It Ar address_family
151Specify the
152address family
153which affects interpretation of the remaining parameters.
154Since an interface can receive transmissions in differing protocols
155with different naming schemes, specifying the address family is recommended.
156The address or protocol families currently
157supported are
158.Dq inet ,
159.Dq inet6 ,
160.Dq atalk ,
161.Dq ipx ,
162.\" .Dq iso ,
163and
164.Dq link .
165.\" and
166.\" .Dq ns .
167The default is
168.Dq inet .
169.Dq ether
170and
171.Dq lladdr
172are synonyms for
173.Dq link .
174.It Ar dest_address
175Specify the address of the correspondent on the other end
176of a point to point link.
177.It Ar interface
178This
179parameter is a string of the form
180.Dq name unit ,
181for example,
182.Dq Li ed0 .
183.It Ar groupname
184List the interfaces in the given group.
185.El
186.Pp
187The following parameters may be set with
188.Nm :
189.Bl -tag -width indent
190.It Cm add
191Another name for the
192.Cm alias
193parameter.
194Introduced for compatibility
195with
196.Bsx .
197.It Cm alias
198Establish an additional network address for this interface.
199This is sometimes useful when changing network numbers, and
200one wishes to accept packets addressed to the old interface.
201If the address is on the same subnet as the first network address
202for this interface, a non-conflicting netmask must be given.
203Usually
204.Li 0xffffffff
205is most appropriate.
206.It Fl alias
207Remove the network address specified.
208This would be used if you incorrectly specified an alias, or it
209was no longer needed.
210If you have incorrectly set an NS address having the side effect
211of specifying the host portion, removing all NS addresses will
212allow you to respecify the host portion.
213.It Cm anycast
214(Inet6 only.)
215Specify that the address configured is an anycast address.
216Based on the current specification,
217only routers may configure anycast addresses.
218Anycast address will not be used as source address of any of outgoing
219IPv6 packets.
220.It Cm arp
221Enable the use of the Address Resolution Protocol
222.Pq Xr arp 4
223in mapping
224between network level addresses and link level addresses (default).
225This is currently implemented for mapping between
226.Tn DARPA
227Internet
228addresses and
229.Tn IEEE
230802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses).
231.It Fl arp
232Disable the use of the Address Resolution Protocol
233.Pq Xr arp 4 .
234.It Cm staticarp
235If the Address Resolution Protocol is enabled,
236the host will only reply to requests for its addresses,
237and will never send any requests.
238.It Fl staticarp
239If the Address Resolution Protocol is enabled,
240the host will perform normally,
241sending out requests and listening for replies.
242.It Cm broadcast
243(Inet only.)
244Specify the address to use to represent broadcasts to the
245network.
246The default broadcast address is the address with a host part of all 1's.
247.It Cm debug
248Enable driver dependent debugging code; usually, this turns on
249extra console error logging.
250.It Fl debug
251Disable driver dependent debugging code.
252.It Cm promisc
253Put interface into permanently promiscuous mode.
254.It Fl promisc
255Disable permanently promiscuous mode.
256.It Cm delete
257Another name for the
258.Fl alias
259parameter.
260.It Cm down
261Mark an interface
262.Dq down .
263When an interface is marked
264.Dq down ,
265the system will not attempt to
266transmit messages through that interface.
267If possible, the interface will be reset to disable reception as well.
268This action does not automatically disable routes using the interface.
269.It Cm group Ar group-name
270Assign the interface to a
271.Dq group .
272Any interface can be in multiple groups.
273.Pp
274Cloned interfaces are members of their interface family group by default.
275For example, a PPP interface such as
276.Em ppp0
277is a member of the PPP interface family group,
278.Em ppp .
279.\" The interface(s) the default route(s) point to are members of the
280.\" .Em egress
281.\" interface group.
282.It Cm -group Ar group-name
283Remove the interface from the given
284.Dq group .
285.It Cm eui64
286(Inet6 only.)
287Fill interface index
288(lowermost 64bit of an IPv6 address)
289automatically.
290.It Cm ipdst
291This is used to specify an Internet host who is willing to receive
292IP packets encapsulating IPX packets bound for a remote network.
293An apparent point to point link is constructed, and
294the address specified will be taken as the IPX address and network
295of the destination.
296.It Cm maclabel Ar label
297If Mandatory Access Control support is enabled in the kernel,
298set the MAC label to
299.Ar label .
300.\" (see
301.\" .Xr maclabel 7 ) .
302.It Cm media Ar type
303If the driver supports the media selection system, set the media type
304of the interface to
305.Ar type .
306Some interfaces support the mutually exclusive use of one of several
307different physical media connectors.
308For example, a 10Mbit/s Ethernet
309interface might support the use of either
310.Tn AUI
311or twisted pair connectors.
312Setting the media type to
313.Cm 10base5/AUI
314would change the currently active connector to the AUI port.
315Setting it to
316.Cm 10baseT/UTP
317would activate twisted pair.
318Refer to the interfaces' driver
319specific documentation or man page for a complete list of the
320available types.
321.It Cm mediaopt Ar opts
322If the driver supports the media selection system, set the specified
323media options on the interface.
324The
325.Ar opts
326argument
327is a comma delimited list of options to apply to the interface.
328Refer to the interfaces' driver specific man page for a complete
329list of available options.
330.It Fl mediaopt Ar opts
331If the driver supports the media selection system, disable the
332specified media options on the interface.
333.It Cm mode Ar mode
334If the driver supports the media selection system, set the specified
335operating mode on the interface to
336.Ar mode .
337For IEEE 802.11 wireless interfaces that support multiple operating modes
338this directive is used to select between 802.11a
339.Pq Cm 11a ,
340802.11b
341.Pq Cm 11b ,
342and 802.11g
343.Pq Cm 11g
344operating modes.
345.It Cm name Ar name
346Set the interface name to
347.Ar name .
348.It Cm rxcsum , txcsum
349If the driver supports user-configurable checksum offloading,
350enable receive (or transmit) checksum offloading on the interface.
351Some drivers may not be able to enable these flags independently
352of each other, so setting one may also set the other.
353The driver will offload as much checksum work as it can reliably
354support, the exact level of offloading varies between drivers.
355.It Fl rxcsum , txcsum
356If the driver supports user-configurable checksum offloading,
357disable receive (or transmit) checksum offloading on the interface.
358These settings may not always be independent of each other.
359.It Cm vlanmtu , vlanhwtag
360If the driver offers user-configurable VLAN support, enable
361reception of extended frames or tag processing in hardware,
362respectively.
363Note that this must be issued on a physical interface associated with
364.Xr vlan 4 ,
365not on a
366.Xr vlan 4
367interface itself.
368.It Fl vlanmtu , vlanhwtag
369If the driver offers user-configurable VLAN support, disable
370reception of extended frames or tag processing in hardware,
371respectively.
372.It Cm polling
373Turn on
374.Xr polling 4
375feature and disable interrupts on the interface, if driver supports
376this mode.
377.It Fl polling
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 addition 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 netmask Ar mask
424.\" (Inet and ISO.)
425(Inet only.)
426Specify how much of the address to reserve for subdividing
427networks into sub-networks.
428The mask includes the network part of the local address
429and the subnet part, which is taken from the host field of the address.
430The mask can be specified as a single hexadecimal number
431with a leading
432.Ql 0x ,
433with a dot-notation Internet address,
434or with a pseudo-network name listed in the network table
435.Xr networks 5 .
436The mask contains 1's for the bit positions in the 32-bit address
437which are to be used for the network and subnet parts,
438and 0's for the host part.
439The mask should contain at least the standard network portion,
440and the subnet field should be contiguous with the network
441portion.
442.Pp
443The netmask can also be specified in CIDR notation after the address.
444See the
445.Ar address
446option above for more information.
447.It Cm prefixlen Ar len
448(Inet6 only.)
449Specify that
450.Ar len
451bits are reserved for subdividing networks into sub-networks.
452The
453.Ar len
454must be integer, and for syntactical reason it must be between 0 to 128.
455It is almost always 64 under the current IPv6 assignment rule.
456If the parameter is omitted, 64 is used.
457.Pp
458The prefix can also be specified using the slash notation after the address.
459See the
460.Ar address
461option above for more information.
462.\" see
463.\" Xr eon 5 .
464.\" .It Cm nsellength Ar n
465.\" .Pf ( Tn ISO
466.\" only)
467.\" This specifies a trailing number of bytes for a received
468.\" .Tn NSAP
469.\" used for local identification, the remaining leading part of which is
470.\" taken to be the
471.\" .Tn NET
472.\" (Network Entity Title).
473.\" The default value is 1, which is conformant to US
474.\" .Tn GOSIP .
475.\" When an ISO address is set in an ifconfig command,
476.\" it is really the
477.\" .Tn NSAP
478.\" which is being specified.
479.\" For example, in
480.\" .Tn US GOSIP ,
481.\" 20 hex digits should be
482.\" specified in the
483.\" .Tn ISO NSAP
484.\" to be assigned to the interface.
485.\" There is some evidence that a number different from 1 may be useful
486.\" for
487.\" .Tn AFI
488.\" 37 type addresses.
489.It Cm range Ar netrange
490Under appletalk, set the interface to respond to a
491.Ar netrange
492of the form
493.Ar startnet Ns - Ns Ar endnet .
494Appletalk uses this scheme instead of
495netmasks though
496.Fx
497implements it internally as a set of netmasks.
498.It Cm remove
499Another name for the
500.Fl alias
501parameter.
502Introduced for compatibility
503with
504.Bsx .
505.It Cm phase
506The argument following this specifies the version (phase) of the
507Appletalk network attached to the interface.
508Values of 1 or 2 are permitted.
509.Sm off
510.It Cm link Op Cm 0 No - Cm 2
511.Sm on
512Enable special processing of the link level of the interface.
513These three options are interface specific in actual effect, however,
514they are in general used to select special modes of operation.
515An example
516of this is to enable SLIP compression, or to select the connector type
517for some Ethernet cards.
518Refer to the man page for the specific driver
519for more information.
520.Sm off
521.It Fl link Op Cm 0 No - Cm 2
522.Sm on
523Disable special processing at the link level with the specified interface.
524.It Cm monitor
525Put the interface in monitor mode.
526No packets are transmitted, and received packets are discarded after
527.Xr bpf 4
528processing.
529.It Fl monitor
530Take the interface out of monitor mode.
531.It Cm up
532Mark an interface
533.Dq up .
534This may be used to enable an interface after an
535.Dq Nm Cm down .
536It happens automatically when setting the first address on an interface.
537If the interface was reset when previously marked down,
538the hardware will be re-initialized.
539.El
540.Pp
541The following parameters are specific to IEEE 802.11 wireless interfaces:
542.Bl -tag -width indent
543.It Cm apbridge
544When operating as an access point, pass packets between
545wireless clients directly (default).
546To instead let them pass up through the
547system and be forwarded using some other mechanism, use
548.Fl apbridge .
549Disabling the internal bridging
550is useful when traffic is to be processed with
551packet filtering.
552.It Cm authmode Ar mode
553Set the desired authentication mode in infrastructure mode.
554Not all adaptors support all modes.
555The set of
556valid modes is
557.Cm none , open , shared
558(shared key),
559.Cm 8021x
560(IEEE 802.1x),
561and
562.Cm wpa
563(IEEE WPA/WPA2/802.11i).
564The
565.Cm 8021x
566and
567.Cm wpa
568modes are only useful when using an authentication service
569(a supplicant for client operation or an authenticator when
570operating as an access point).
571Modes are case insensitive.
572.It Cm bintval Ar interval
573Set the interval at which beacon frames are sent when operating in
574ad-hoc or ap mode.
575The
576.Ar interval
577parameter is specified in TU's (1/1024 msecs).
578By default beacon frames are transmitted every 100 TU's.
579.It Cm bssid Ar address
580Specify the MAC address of the access point to use when operating
581as a station in a BSS network.
582This overrides any automatic selection done by the system.
583To disable a previously selected access point, supply
584.Cm any , none ,
585or
586.Cm -
587for the address.
588This option is useful when more than one access points have the same SSID.
589Another name for the
590.Cm bssid
591parameter is
592.Cm ap .
593.It Cm burst
594Enable packet bursting.
595Packet bursting is a transmission technique whereby the wireless
596medium is acquired once to send multiple frames and the interframe
597spacing is reduced.
598This technique can significantly increase throughput by reducing
599transmission overhead.
600Packet bursting is supported by the 802.11e QoS specification
601and some devices that do not support QoS may still be capable.
602By default packet bursting is enabled if a device is capable
603of doing it.
604To disable packet bursting, use
605.Fl burst .
606.It Cm chanlist Ar channels
607Set the desired channels to use when scanning for access
608points, neighbors in an IBSS network, or looking for unoccupied
609channels when operating as an access point.
610The set of channels is specified as a comma-separated list with
611each element in the list representing either a single channel number or a range
612of the form
613.Dq Li a-b .
614Channel numbers must be in the range 1 to 255 and be permissible
615according to the operating characteristics of the device.
616.It Cm channel Ar number
617Set a single desired channel.
618Channels range from 1 to 255, but the exact selection available
619depends on the region your adaptor was manufactured for.
620Setting
621the channel to
622.Li 0 ,
623.Cm any ,
624or
625.Cm -
626will give you the default for your adaptor.
627Some
628adaptors ignore this setting unless you are in ad-hoc mode.
629Alternatively the frequency, in megahertz, may be specified
630instead of the channel number.
631.It Cm deftxkey Ar index
632Set the default key to use for transmission.
633Typically this is only set when using WEP encryption.
634The
635.Cm weptxkey
636is an alias for this request; it is provided for backwards compatibility.
637.It Cm dtimperiod Ar period
638Set the
639DTIM
640period for transmitting buffered multicast data frames when
641operating in ap mode.
642The
643.Ar period
644specifies the number of beacon intervals between DTIM
645and must be in the range 1 to 15.
646By default DTIM is 1 (i.e., DTIM occurs at each beacon).
647.It Cm fragthreshold Ar length
648Set the threshold for which transmitted frames are broken into fragments.
649The
650.Ar length
651argument is the frame size in bytes and must be in the range 256 to 2346.
652Setting
653.Ar length
654to
655.Li 2346 ,
656.Cm any ,
657or
658.Cm -
659disables transmit fragmentation.
660Not all adaptors honor the fragmentation threshold.
661.It Cm hidessid
662When operating as an access point, do not broadcast the SSID
663in beacon frames or respond to probe request frames unless
664they are directed to the ap (i.e., they include the ap's SSID).
665By default, the SSID is included in beacon frames and
666undirected probe request frames are answered.
667To re-enable the broadcast of the SSID etc., use
668.Fl hidessid .
669.It Cm list active
670Display the list of channels available for use taking into account
671any restrictions set with the
672.Cm chanlist
673directive.
674See the description of
675.Cm list chan
676for more information.
677.It Cm list caps
678Display the adaptor's capabilities, including the operating
679modes supported.
680.It Cm list chan
681Display the list of channels available for use.
682Channels are shown with their IEEE channel number, equivalent
683frequency, and usage modes.
684Channels identified as
685.Ql 11g
686are also usable in
687.Ql 11b
688mode.
689Channels identified as
690.Ql 11a Turbo
691may be used only for Atheros' Static Turbo mode
692.Pq specified with Cm mediaopt turbo .
693Channels marked with a
694.Ql *
695have a regulatory constraint that they be passively scanned.
696This means a station is not permitted to transmit on the channel until
697it identifies the channel is being used for 802.11 communication;
698typically by hearing a beacon frame from an access point operating
699on the channel.
700.Cm list freq
701is another way of requesting this information.
702.It Cm list mac
703Display the current MAC Access Control List state.
704Each address is prefixed with a character that indicates the
705current policy applied to it:
706.Ql +
707indicates the address is allowed access,
708.Ql -
709indicates the address is denied access,
710.Ql *
711indicates the address is present but the current policy open
712(so the ACL is not consulted).
713.It Cm list scan
714Display the access points and/or ad-hoc neighbors
715located in the vicinity.
716This information may be updated automatically by the adaptor
717and/or with a
718.Cm scan
719request.
720.Cm list ap
721is another way of requesting this information.
722.It Cm list sta
723When operating as an access point display the stations that are
724currently associated.
725When operating in ad-hoc mode display stations identified as
726neighbors in the IBSS.
727Capabilities advertised by the stations are described under
728the
729.Cm scan
730request.
731Depending on the capabilities of the stations the following
732flags can be included in the output:
733.Bl -tag -width 3n
734.It Li A
735Authorized.
736Indicates that the station is permitted to send/receive data frames.
737.It Li E
738Extended Rate Phy (ERP).
739Indicates that the station is operating in an 802.11g network
740using extended transmit rates.
741.It Li P
742Power Save.
743Indicates that the station is operating in power save mode.
744.It Li Q
745Quality of Service (QoS).
746Indicates that the station is using QoS encapsulation for
747data frame.
748QoS encapsulation is enabled only when WME mode is enabled.
749.El
750.It Cm list wme
751Display the current parameters to use when operating in WME mode.
752When WME mode is enabled for an adaptor this information will be
753displayed with the regular status; this command is mostly useful
754for examining parameters when WME mode is disabled.
755See the description of the
756.Cm wme
757directive for information on the various parameters.
758.It Cm mcastrate Ar rate
759Set the rate for transmitting multicast/broadcast frames.
760Rates are specified as megabits/second in decimal; e.g. 5.5 for 5.5 Mb/s.
761This rate should be valid for the current operating conditions;
762if an invalid rate is specified drivers are free to chose an
763appropriate rate.
764.It Cm powersave
765Enable powersave operation.
766When operating as a client, the station will conserve power by
767periodically turning off the radio and listening for
768messages from the access point telling it there are packets waiting.
769The station must then retrieve the packets.
770When operating as an access point, the station must honor power
771save operation of associated clients.
772Not all devices support power save operation, either as a client
773or as an access point.
774Use
775.Fl powersave
776to disable powersave operation.
777.It Cm powersavesleep Ar sleep
778Set the desired max powersave sleep time in milliseconds.
779.It Cm protmode Ar technique
780For interfaces operating in 802.11g, use the specified
781.Ar technique
782for protecting OFDM frames in a mixed 11b/11g network.
783The set of valid techniques is
784.Cm off , cts
785(CTS to self),
786and
787.Cm rtscts
788(RTS/CTS).
789Technique names are case insensitive.
790.It Cm pureg
791When operating as an access point in 802.11g mode allow only
79211g-capable stations to associate (11b-only stations are not
793permitted to associate).
794To allow both 11g and 11b-only stations to associate, use
795.Fl pureg .
796.It Cm roaming Ar mode
797When operating as a station, control how the system will
798behave when communication with the current access point
799is broken.
800The
801.Ar mode
802argument may be one of
803.Cm device
804(leave it to the hardware device to decide),
805.Cm auto
806(handle either in the device or the operating system\[em]as appropriate),
807.Cm manual
808(do nothing until explicitly instructed).
809By default, the device is left to handle this if it is
810capable; otherwise, the operating system will automatically
811attempt to reestablish communication.
812Manual mode is mostly useful when an application wants to
813control the selection of an access point.
814.It Cm rtsthreshold Ar length
815Set the threshold for which
816transmitted frames are preceded by transmission of an
817RTS
818control frame.
819The
820.Ar length
821argument
822is the frame size in bytes and must be in the range 1 to 2346.
823Setting
824.Ar length
825to
826.Li 2346 ,
827.Cm any ,
828or
829.Cm -
830disables transmission of RTS frames.
831Not all adaptors support setting the RTS threshold.
832.It Cm ssid Ar ssid
833Set the desired Service Set Identifier (aka network name).
834The SSID is a string up to 32 characters
835in length and may be specified as either a normal string or in
836hexadecimal when preceded by
837.Ql 0x .
838Additionally, the SSID may be cleared by setting it to
839.Ql - .
840.It Cm scan
841Initiate a scan of neighboring stations, wait for it to complete, and
842display all stations found.
843Only the super-user can initiate a scan.
844Depending on the capabilities of the APs, the following
845flags can be included in the output:
846.Bl -tag -width 3n
847.It Li A
848Channel Agility.
849Indicates that the station support channel hopping as described by the
850IEEE 802.11b specification.
851.It Li B
852Packet Binary Convolution Code (PBCC).
853A modulation alternative to the standard OFDM method.
854.It Dv C
855Pollreq
856.It Dv c
857Pollable
858.It Dv D
859Direct Sequence Spread Spectrum (DSSSOFDM).
860Indicates the the station supports DSSS modulation.
861.It Li E
862Extended Service Set (ESS).
863Indicates that the station is part of an infrastructure network
864(in contrast to an IBSS/ad-hoc network).
865.It Li I
866IBSS/ad-hoc network.
867Indicates that the station is part of an ad-hoc network
868(in contrast to an ESS network).
869.It Li P
870Privacy.
871Data confidentiality is required for all data frames
872exchanged within the BSS.
873This means that this BSS requires the station to
874use cryptographic means such as WEP, TKIP or AES-CCMP to
875encrypt/decrypt data frames being exchanged with others.
876.It Dv R
877Robust Security Network (RSN).
878Indicates that the station supports the IEEE 802.11i authentication
879and key management protocol.
880.It Li S
881Short Preamble.
882Indicates that the network is using short preambles (defined
883in 802.11b High Rate/DSSS PHY, short preamble utilizes a
88456 bit sync field in contrast to a 128 bit field used in long
885preamble mode).
886.It Li s
887Short slot time.
888Indicates that the network is using a short slot time.
889.El
890.Pp
891The
892.Cm list scan
893request can be used to show recent scan results without
894initiating a new scan.
895.It Cm stationname Ar name
896Set the name of this station.
897It appears that the station name is not really part of the IEEE 802.11
898protocol though all interfaces seem to support it.
899As such it only
900seems to be meaningful to identical or virtually identical equipment.
901Setting the station name is identical in syntax to setting the SSID.
902.It Cm txpower Ar power
903Set the power used to transmit frames.
904The
905.Ar power
906argument
907is a unitless value in the range 0 to 100 that is interpreted
908by drivers to derive a device-specific value.
909Out of range values are truncated.
910Typically only a few discreet power settings are available and
911the driver will use the setting closest to the specified value.
912Not all adaptors support changing the transmit power.
913.It Cm wepmode Ar mode
914Set the desired WEP mode.
915Not all adaptors support all modes.
916The set of valid modes is
917.Cm off , on ,
918and
919.Cm mixed .
920The
921.Cm mixed
922mode explicitly tells the adaptor to allow association with access
923points which allow both encrypted and unencrypted traffic.
924On these adaptors,
925.Cm on
926means that the access point must only allow encrypted connections.
927On other adaptors,
928.Cm on
929is generally another name for
930.Cm mixed .
931Modes are case insensitive.
932.It Cm weptxkey Ar index
933Set the WEP key to be used for transmission.
934This is the same as setting the default transmission key with
935.Cm deftxkey .
936.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key
937Set the selected WEP key.
938If an
939.Ar index
940is not given, key 1 is set.
941A WEP key will be either 5 or 13
942characters (40 or 104 bits) depending of the local network and the
943capabilities of the adaptor.
944It may be specified either as a plain
945string or as a string of hexadecimal digits preceded by
946.Ql 0x .
947For maximum portability, hex keys are recommended;
948the mapping of text keys to WEP encryption is usually driver-specific.
949In particular, the
950.Tn Windows
951drivers do this mapping differently to
952.Fx .
953A key may be cleared by setting it to
954.Ql - .
955If WEP is supported then there are at least four keys.
956Some adaptors support more than four keys.
957If that is the case, then the first four keys
958(1-4) will be the standard temporary keys and any others will be adaptor
959specific keys such as permanent keys stored in NVRAM.
960.It Cm wme
961Enable Wireless Multimedia Extensions (WME) support, if available,
962for the specified interface.
963WME is a subset of the IEEE 802.11e standard to support the
964efficient communication of realtime and multimedia data.
965To disable WME support, use
966.Fl wme .
967.Pp
968The following parameters are meaningful only when WME support is in use.
969Parameters are specified per-AC (Access Category) and
970split into those that are used by a station when acting
971as an access point and those for client stations in the BSS.
972The latter are received from the access point and may not be changed
973(at the station).
974The following Access Categories are recognized:
975.Pp
976.Bl -tag -width ".Cm AC_BK" -compact
977.It Cm AC_BE
978(or
979.Cm BE )
980best effort delivery,
981.It Cm AC_BK
982(or
983.Cm BK )
984background traffic,
985.It Cm AC_VI
986(or
987.Cm VI )
988video traffic,
989.It Cm AC_VO
990(or
991.Cm VO )
992voice traffic.
993.El
994.Pp
995AC parameters are case-insensitive.
996Traffic classification is done in the operating system using the
997vlan priority associated with data frames or the
998ToS (Type of Service) indication in IP-encapsulated frames.
999If neither information is present, traffic is assigned to the
1000Best Effort (BE) category.
1001.Bl -tag -width indent
1002.It Cm ack Ar ac
1003Set the ACK policy for QoS transmissions by the local station;
1004this controls whether or not data frames transmitted by a station
1005require an ACK response from the receiving station.
1006To disable waiting for an ACK use
1007.Fl ack .
1008This parameter is applied only to the local station.
1009.It Cm acm Ar ac
1010Enable the Admission Control Mandatory (ACM) mechanism
1011for transmissions by the local station.
1012To disable the ACM use
1013.Fl acm .
1014On stations in a BSS this parameter is read-only and indicates
1015the setting received from the access point.
1016NB: ACM is not supported right now.
1017.It Cm aifs Ar ac Ar count
1018Set the Arbitration Inter Frame Spacing (AIFS)
1019channel access parameter to use for transmissions
1020by the local station.
1021On stations in a BSS this parameter is read-only and indicates
1022the setting received from the access point.
1023.It Cm cwmin Ar ac Ar count
1024Set the CWmin channel access parameter to use for transmissions
1025by the local station.
1026On stations in a BSS this parameter is read-only and indicates
1027the setting received from the access point.
1028.It Cm cwmax Ar ac Ar count
1029Set the CWmax channel access parameter to use for transmissions
1030by the local station.
1031On stations in a BSS this parameter is read-only and indicates
1032the setting received from the access point.
1033.It Cm txoplimit Ar ac Ar limit
1034Set the Transmission Opportunity Limit channel access parameter
1035to use for transmissions by the local station.
1036This parameter defines an interval of time when a WME station
1037has the right to initiate transmissions onto the wireless medium.
1038On stations in a BSS this parameter is read-only and indicates
1039the setting received from the access point.
1040.It Cm bss:aifs Ar ac Ar count
1041Set the AIFS channel access parameter to send to stations in a BSS.
1042This parameter is meaningful only when operating in ap mode.
1043.It Cm bss:cwmin Ar ac Ar count
1044Set the CWmin channel access parameter to send to stations in a BSS.
1045This parameter is meaningful only when operating in ap mode.
1046.It Cm bss:cwmax Ar ac Ar count
1047Set the CWmax channel access parameter to send to stations in a BSS.
1048This parameter is meaningful only when operating in ap mode.
1049.It Cm bss:txoplimit Ar ac Ar limit
1050Set the TxOpLimit channel access parameter to send to stations in a BSS.
1051This parameter is meaningful only when operating in ap mode.
1052.El
1053.El
1054.Pp
1055The following parameters support an optional access control list
1056feature available with some adaptors when operating in ap mode; see
1057.Xr wlan_acl 4 .
1058This facility allows an access point to accept/deny association
1059requests based on the MAC address of the station.
1060Note that this feature does not significantly enhance security
1061as MAC address spoofing is easy to do.
1062.Bl -tag -width indent
1063.It Cm mac:add Ar address
1064Add the specified MAC address to the database.
1065Depending on the policy setting association requests from the
1066specified station will be allowed or denied.
1067.It Cm mac:allow
1068Set the ACL policy to permit association only by
1069stations registered in the database.
1070.It Cm mac:del Ar address
1071Delete the specified MAC address from the database.
1072.It Cm mac:deny
1073Set the ACL policy to deny association only by
1074stations registered in the database.
1075.It Cm mac:kick Ar address
1076Force the specified station to be deauthenticated.
1077This typically is done to block a station after updating the
1078address database.
1079.It Cm mac:open
1080Set the ACL policy to allow all stations to associate.
1081.It Cm mac:flush
1082Delete all entries in the database.
1083.El
1084.Pp
1085The following parameters are for compatibility with other systems:
1086.Bl -tag -width indent
1087.It Cm nwid Ar ssid
1088Another name for the
1089.Cm ssid
1090parameter.
1091Included for
1092.Nx
1093compatibility.
1094.It Cm station Ar name
1095Another name for the
1096.Cm stationname
1097parameter.
1098Included for
1099.Bsx
1100compatibility.
1101.It Cm wep
1102Another way of saying
1103.Cm wepmode on .
1104Included for
1105.Bsx
1106compatibility.
1107.It Fl wep
1108Another way of saying
1109.Cm wepmode off .
1110Included for
1111.Bsx
1112compatibility.
1113.It Cm nwkey key
1114Another way of saying:
1115.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" .
1116Included for
1117.Nx
1118compatibility.
1119.It Cm nwkey Xo
1120.Sm off
1121.Ar n : k1 , k2 , k3 , k4
1122.Sm on
1123.Xc
1124Another way of saying
1125.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" .
1126Included for
1127.Nx
1128compatibility.
1129.It Fl nwkey
1130Another way of saying
1131.Cm wepmode off .
1132Included for
1133.Nx
1134compatibility.
1135.El
1136.Pp
1137The following parameters are specific to bridge interfaces:
1138.Bl -tag -width indent
1139.It Cm addm Ar interface
1140Add the interface named by
1141.Ar interface
1142as a member of the bridge.
1143The interface is put into promiscuous mode
1144so that it can receive every packet sent on the network.
1145.It Cm deletem Ar interface
1146Remove the interface named by
1147.Ar interface
1148from the bridge.
1149Promiscuous mode is disabled on the interface when
1150it is removed from the bridge.
1151.It Cm maxaddr Ar size
1152Set the size of the bridge address cache to
1153.Ar size .
1154The default is 100 entries.
1155.It Cm timeout Ar seconds
1156Set the timeout of address cache entries to
1157.Ar seconds
1158seconds.
1159If
1160.Ar seconds
1161is zero, then address cache entries will not be expired.
1162The default is 240 seconds.
1163.It Cm addr
1164Display the addresses that have been learned by the bridge.
1165.It Cm static Ar interface-name Ar address
1166Add a static entry into the address cache pointing to
1167.Ar interface-name .
1168Static entries are never aged out of the cache or re-placed, even if the
1169address is seen on a different interface.
1170.It Cm deladdr Ar address
1171Delete
1172.Ar address
1173from the address cache.
1174.It Cm flush
1175Delete all dynamically-learned addresses from the address cache.
1176.It Cm flushall
1177Delete all addresses, including static addresses, from the address cache.
1178.It Cm discover Ar interface
1179Mark an interface as a
1180.Dq discovering
1181interface.
1182When the bridge has no address cache entry
1183(either dynamic or static)
1184for the destination address of a packet,
1185the bridge will forward the packet to all
1186member interfaces marked as
1187.Dq discovering .
1188This is the default for all interfaces added to a bridge.
1189.It Cm -discover Ar interface
1190Clear the
1191.Dq discovering
1192attribute on a member interface.
1193For packets without the
1194.Dq discovering
1195attribute, the only packets forwarded on the interface are broadcast
1196or multicast packets and packets for which the destination address
1197is known to be on the interface's segment.
1198.It Cm learn Ar interface
1199Mark an interface as a
1200.Dq learning
1201interface.
1202When a packet arrives on such an interface, the source
1203address of the packet is entered into the address cache as being a
1204destination address on the interface's segment.
1205This is the default for all interfaces added to a bridge.
1206.It Cm -learn Ar interface
1207Clear the
1208.Dq learning
1209attribute on a member interface.
1210.It Cm span Ar interface
1211Add the interface named by
1212.Ar interface
1213as a span port on the bridge.
1214Span ports transmit a copy of every frame received by the bridge.
1215This is most useful for snooping a bridged network passively on
1216another host connected to one of the span ports of the bridge.
1217.It Cm -span Ar interface
1218Delete the interface named by
1219.Ar interface
1220from the list of span ports of the bridge.
1221.It Cm stp Ar interface
1222Enable Spanning Tree protocol on
1223.Ar interface .
1224The
1225.Xr if_bridge 4
1226driver has support for the IEEE 802.1D Spanning Tree protocol (STP).
1227Spanning Tree is used to detect and remove loops in a network topology.
1228.It Cm -stp Ar interface
1229Disable Spanning Tree protocol on
1230.Ar interface .
1231This is the default for all interfaces added to a bridge.
1232.It Cm maxage Ar seconds
1233Set the time that a Spanning Tree protocol configuration is valid.
1234The default is 20 seconds.
1235The minimum is 1 second and the maximum is 255 seconds.
1236.It Cm fwddelay Ar seconds
1237Set the time that must pass before an interface begins forwarding
1238packets when Spanning Tree is enabled.
1239The default is 15 seconds.
1240The minimum is 1 second and the maximum is 255 seconds.
1241.It Cm hellotime Ar seconds
1242Set the time between broadcasting of Spanning Tree protocol
1243configuration messages.
1244The default is 2 seconds.
1245The minimum is 1 second and the maximum is 255 seconds.
1246.It Cm priority Ar value
1247Set the bridge priority for Spanning Tree.
1248The default is 32768.
1249The minimum is 0 and the maximum is 65536.
1250.It Cm ifpriority Ar interface Ar value
1251Set the Spanning Tree priority of
1252.Ar interface
1253to
1254.Ar value .
1255The default is 128.
1256The minimum is 0 and the maximum is 255.
1257.It Cm ifpathcost Ar interface Ar value
1258Set the Spanning Tree path cost of
1259.Ar interface
1260to
1261.Ar value .
1262The default is 55.
1263The minimum is 0 and the maximum is 65535.
1264.El
1265.Pp
1266The following parameters are specific to IP tunnel interfaces,
1267.Xr gif 4 :
1268.Bl -tag -width indent
1269.It Cm tunnel Ar src_addr dest_addr
1270Configure the physical source and destination address for IP tunnel
1271interfaces.
1272The arguments
1273.Ar src_addr
1274and
1275.Ar dest_addr
1276are interpreted as the outer source/destination for the encapsulating
1277IPv4/IPv6 header.
1278.It Fl tunnel
1279Unconfigure the physical source and destination address for IP tunnel
1280interfaces previously configured with
1281.Cm tunnel .
1282.It Cm deletetunnel
1283Another name for the
1284.Fl tunnel
1285parameter.
1286.El
1287.Pp
1288The following parameters are specific to
1289.Xr pfsync 4
1290interfaces:
1291.Bl -tag -width indent
1292.It Cm maxupd Ar n
1293Set the maximum number of updates for a single state which
1294can be collapsed into one.
1295This is an 8-bit number; the default value is 128.
1296.El
1297.Pp
1298The following parameters are specific to
1299.Xr vlan 4
1300interfaces:
1301.Bl -tag -width indent
1302.It Cm vlan Ar vlan_tag
1303Set the VLAN tag value to
1304.Ar vlan_tag .
1305This value is a 16-bit number which is used to create an 802.1Q
1306VLAN header for packets sent from the
1307.Xr vlan 4
1308interface.
1309Note that
1310.Cm vlan
1311and
1312.Cm vlandev
1313must both be set at the same time.
1314.It Cm vlandev Ar iface
1315Associate the physical interface
1316.Ar iface
1317with a
1318.Xr vlan 4
1319interface.
1320Packets transmitted through the
1321.Xr vlan 4
1322interface will be
1323diverted to the specified physical interface
1324.Ar iface
1325with 802.1Q VLAN encapsulation.
1326Packets with 802.1Q encapsulation received
1327by the parent interface with the correct VLAN tag will be diverted to
1328the associated
1329.Xr vlan 4
1330pseudo-interface.
1331The
1332.Xr vlan 4
1333interface is assigned a
1334copy of the parent interface's flags and the parent's ethernet address.
1335The
1336.Cm vlandev
1337and
1338.Cm vlan
1339must both be set at the same time.
1340If the
1341.Xr vlan 4
1342interface already has
1343a physical interface associated with it, this command will fail.
1344To
1345change the association to another physical interface, the existing
1346association must be cleared first.
1347.Pp
1348Note: if the hardware tagging capability
1349is set on the parent interface, the
1350.Xr vlan 4
1351pseudo
1352interface's behavior changes:
1353the
1354.Xr vlan 4
1355interface recognizes that the
1356parent interface supports insertion and extraction of VLAN tags on its
1357own (usually in firmware) and that it should pass packets to and from
1358the parent unaltered.
1359.It Fl vlandev Op Ar iface
1360If the driver is a
1361.Xr vlan 4
1362pseudo device, disassociate the parent interface from it.
1363This breaks the link between the
1364.Xr vlan 4
1365interface and its parent,
1366clears its VLAN tag, flags and its link address and shuts the interface down.
1367The
1368.Ar iface
1369argument is useless and hence deprecated.
1370.El
1371.Pp
1372The following parameters are specific to
1373.Xr carp 4
1374interfaces:
1375.Bl -tag -width indent
1376.It Cm advbase Ar seconds
1377Specifies the base of the advertisement interval in seconds.
1378The acceptable values are 1 to 255.
1379The default value is 1.
1380.\" The default value is
1381.\" .Dv CARP_DFLTINTV .
1382.It Cm advskew Ar interval
1383Specifies the skew to add to the base advertisement interval to
1384make one host advertise slower than another host.
1385It is specified in 1/256 of seconds.
1386The acceptable values are 1 to 254.
1387The default value is 0.
1388.It Cm pass Ar phrase
1389Set the authentication key to
1390.Ar phrase .
1391.It Cm vhid Ar n
1392Set the virtual host ID.
1393This is a required setting.
1394Acceptable values are 1 to 255.
1395.El
1396.Pp
1397The
1398.Nm
1399utility displays the current configuration for a network interface
1400when no optional parameters are supplied.
1401If a protocol family is specified,
1402.Nm
1403will report only the details specific to that protocol family.
1404.Pp
1405If the
1406.Fl m
1407flag is passed before an interface name,
1408.Nm
1409will display the capability list and all
1410of the supported media for the specified interface.
1411If
1412.Fl L
1413flag is supplied, address lifetime is displayed for IPv6 addresses,
1414as time offset string.
1415.Pp
1416Optionally, the
1417.Fl a
1418flag may be used instead of an interface name.
1419This flag instructs
1420.Nm
1421to display information about all interfaces in the system.
1422The
1423.Fl d
1424flag limits this to interfaces that are down, and
1425.Fl u
1426limits this to interfaces that are up.
1427When no arguments are given,
1428.Fl a
1429is implied.
1430.Pp
1431The
1432.Fl l
1433flag may be used to list all available interfaces on the system, with
1434no other additional information.
1435Use of this flag is mutually exclusive
1436with all other flags and commands, except for
1437.Fl d
1438(only list interfaces that are down)
1439and
1440.Fl u
1441(only list interfaces that are up).
1442.Pp
1443The
1444.Fl v
1445flag may be used to get more verbose status for an interface.
1446.Pp
1447The
1448.Fl C
1449flag may be used to list all of the interface cloners available on
1450the system, with no additional information.
1451Use of this flag is mutually exclusive with all other flags and commands.
1452.Pp
1453The
1454.Fl k
1455flag causes keying information for the interface, if available, to be
1456printed.
1457For example, the values of 802.11 WEP keys will be printed, if accessible to
1458the current user.
1459This information is not printed by default, as it may be considered
1460sensitive.
1461.Pp
1462Only the super-user may modify the configuration of a network interface.
1463.Sh NOTES
1464The media selection system is relatively new and only some drivers support
1465it (or have need for it).
1466.Sh DIAGNOSTICS
1467Messages indicating the specified interface does not exist, the
1468requested address is unknown, or the user is not privileged and
1469tried to alter an interface's configuration.
1470.Sh SEE ALSO
1471.Xr netstat 1 ,
1472.Xr carp 4 ,
1473.Xr netintro 4 ,
1474.Xr pfsync 4 ,
1475.Xr polling 4 ,
1476.Xr vlan 4 ,
1477.\" .Xr eon 5 ,
1478.Xr rc 8 ,
1479.Xr routed 8 ,
1480.Xr sysctl 8
1481.Sh HISTORY
1482The
1483.Nm
1484utility appeared in
1485.Bx 4.2 .
1486.Sh BUGS
1487Basic IPv6 node operation requires a link-local address on each
1488interface configured for IPv6.
1489Normally, such an address is automatically configured by the
1490kernel on each interface added to the system; this behaviour may
1491be disabled by setting the sysctl MIB variable
1492.Va net.inet6.ip6.auto_linklocal
1493to 0.
1494.Pp
1495If you delete such an address using
1496.Nm ,
1497the kernel may act very oddly.
1498Do this at your own risk.
1499