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28.\" From: @(#)ifconfig.8 8.3 (Berkeley) 1/5/94
29.\" $FreeBSD: src/sbin/ifconfig/ifconfig.8,v 1.85 2004/07/27 09:51:49 yar Exp $
30.\" $DragonFly: src/sbin/ifconfig/ifconfig.8,v 1.8 2005/10/13 10:57:50 swildner Exp $
31.\"
32.Dd July 26, 2004
33.Dt IFCONFIG 8
34.Os
35.Sh NAME
36.Nm ifconfig
37.Nd configure network interface parameters
38.Sh SYNOPSIS
39.Nm
40.Op Fl L
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 Ar address_family
60.Nm
61.Fl l
62.Op Fl d
63.Op Fl u
64.Op Ar address_family
65.Nm
66.Op Fl L
67.Op Fl d
68.Op Fl m
69.Op Fl u
70.Op Fl C
71.Sh DESCRIPTION
72The
73.Nm
74utility is used to assign an address
75to a network interface and/or configure
76network interface parameters.
77The
78.Nm
79utility must be used at boot time to define the network address
80of each interface present on a machine; it may also be used at
81a later time to redefine an interface's address
82or other operating parameters.
83.Pp
84The following options are available:
85.Bl -tag -width indent
86.It Ar address
87For the
88.Tn DARPA Ns -Internet
89family,
90the address is either a host name present in the host name data
91base,
92.Xr hosts 5 ,
93or a
94.Tn DARPA
95Internet address expressed in the Internet standard
96.Dq dot notation .
97.Pp
98It is also possible to use the CIDR notation (also known as the
99slash notation) to include the netmask.
100That is, one can specify an address like
101.Li 192.168.0.1/16 .
102.Pp
103For
104.Dq inet6
105family, it is also possible to specify the prefix length using the slash
106notation, like
107.Li ::1/128 .
108See the
109.Cm prefixlen
110parameter below for more information.
111.\" For the Xerox Network Systems(tm) family,
112.\" addresses are
113.\" .Ar net:a.b.c.d.e.f ,
114.\" where
115.\" .Ar net
116.\" is the assigned network number (in decimal),
117.\" and each of the six bytes of the host number,
118.\" .Ar a
119.\" through
120.\" .Ar f ,
121.\" are specified in hexadecimal.
122.\" The host number may be omitted on IEEE 802 protocol
123.\" (Ethernet, FDDI, and Token Ring) interfaces,
124.\" which use the hardware physical address,
125.\" and on interfaces other than the first.
126.\" For the
127.\" .Tn ISO
128.\" family, addresses are specified as a long hexadecimal string,
129.\" as in the Xerox family.
130.\" However, two consecutive dots imply a zero
131.\" byte, and the dots are optional, if the user wishes to (carefully)
132.\" count out long strings of digits in network byte order.
133.Pp
134The link-level
135.Pq Dq link
136address
137is specified as a series of colon-separated hex digits.
138This can be used to
139e.g.\& set a new MAC address on an ethernet interface, though the
140mechanism used is not ethernet-specific.
141If the interface is already
142up when this option is used, it will be briefly brought down and
143then brought back up again in order to ensure that the receive
144filter in the underlying ethernet hardware is properly reprogrammed.
145.It Ar address_family
146Specify the
147address family
148which affects interpretation of the remaining parameters.
149Since an interface can receive transmissions in differing protocols
150with different naming schemes, specifying the address family is recommended.
151The address or protocol families currently
152supported are
153.Dq inet ,
154.Dq inet6 ,
155.Dq atalk ,
156.Dq ipx ,
157.\" .Dq iso ,
158and
159.Dq link .
160.\" and
161.\" .Dq ns .
162The default is
163.Dq inet .
164.Dq ether
165and
166.Dq lladdr
167are synonyms for
168.Dq link .
169.It Ar dest_address
170Specify the address of the correspondent on the other end
171of a point to point link.
172.It Ar interface
173This
174parameter is a string of the form
175.Dq name unit ,
176for example,
177.Dq Li ed0 .
178.El
179.Pp
180The following parameters may be set with
181.Nm :
182.Bl -tag -width indent
183.It Cm add
184Another name for the
185.Cm alias
186parameter.
187Introduced for compatibility
188with
189.Bsx .
190.It Cm alias
191Establish an additional network address for this interface.
192This is sometimes useful when changing network numbers, and
193one wishes to accept packets addressed to the old interface.
194If the address is on the same subnet as the first network address
195for this interface, a non-conflicting netmask must be given.
196Usually
197.Li 0xffffffff
198is most appropriate.
199.It Fl alias
200Remove the network address specified.
201This would be used if you incorrectly specified an alias, or it
202was no longer needed.
203If you have incorrectly set an NS address having the side effect
204of specifying the host portion, removing all NS addresses will
205allow you to respecify the host portion.
206.It Cm anycast
207(Inet6 only.)
208Specify that the address configured is an anycast address.
209Based on the current specification,
210only routers may configure anycast addresses.
211Anycast address will not be used as source address of any of outgoing
212IPv6 packets.
213.It Cm arp
214Enable the use of the Address Resolution Protocol
215.Pq Xr arp 4
216in mapping
217between network level addresses and link level addresses (default).
218This is currently implemented for mapping between
219.Tn DARPA
220Internet
221addresses and
222.Tn IEEE
223802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses).
224.It Fl arp
225Disable the use of the Address Resolution Protocol
226.Pq Xr arp 4 .
227.It Cm broadcast
228(Inet only.)
229Specify the address to use to represent broadcasts to the
230network.
231The default broadcast address is the address with a host part of all 1's.
232.It Cm debug
233Enable driver dependent debugging code; usually, this turns on
234extra console error logging.
235.It Fl debug
236Disable driver dependent debugging code.
237.It Cm polling
238Enable
239.Xr polling 4
240for the interface.
241.It Fl polling
242Disable
243.Xr polling 4
244for the interface.
245.It Cm promisc
246Put interface into permanently promiscuous mode.
247.It Fl promisc
248Disable permanently promiscuous mode.
249.It Cm delete
250Another name for the
251.Fl alias
252parameter.
253.It Cm down
254Mark an interface
255.Dq down .
256When an interface is marked
257.Dq down ,
258the system will not attempt to
259transmit messages through that interface.
260If possible, the interface will be reset to disable reception as well.
261This action does not automatically disable routes using the interface.
262.It Cm eui64
263(Inet6 only.)
264Fill interface index
265(lowermost 64bit of an IPv6 address)
266automatically.
267.\" .It Cm ipdst
268.\" This is used to specify an Internet host who is willing to receive
269.\" ip packets encapsulating NS packets bound for a remote network.
270.\" An apparent point to point link is constructed, and
271.\" the address specified will be taken as the NS address and network
272.\" of the destination.
273.\" IP encapsulation of
274.\" .Tn CLNP
275.\" packets is done differently.
276.It Cm media Ar type
277If the driver supports the media selection system, set the media type
278of the interface to
279.Ar type .
280Some interfaces support the mutually exclusive use of one of several
281different physical media connectors.
282For example, a 10Mb/s Ethernet
283interface might support the use of either
284.Tn AUI
285or twisted pair connectors.
286Setting the media type to
287.Dq Li 10base5/AUI
288would change the currently active connector to the AUI port.
289Setting it to
290.Dq Li 10baseT/UTP
291would activate twisted pair.
292Refer to the interfaces' driver
293specific documentation or man page for a complete list of the
294available types.
295.It Cm mediaopt Ar opts
296If the driver supports the media selection system, set the specified
297media options on the interface.
298The
299.Ar opts
300argument
301is a comma delimited list of options to apply to the interface.
302Refer to the interfaces' driver specific man page for a complete
303list of available options.
304.It Fl mediaopt Ar opts
305If the driver supports the media selection system, disable the
306specified media options on the interface.
307.It Cm mode Ar mode
308If the driver supports the media selection system, set the specified
309operating mode on the interface to
310.Ar mode .
311For IEEE 802.11 wireless interfaces that support multiple operating modes
312this directive is used to select between 802.11a
313.Pq Dq Li 11a ,
314802.11b
315.Pq Dq Li 11b ,
316and 802.11g
317.Pq Dq Li 11g
318operating modes.
319.It Cm name Ar name
320Set the interface name to
321.Ar name .
322.It Cm rxcsum , txcsum
323If the driver supports user-configurable checksum offloading,
324enable receive (or transmit) checksum offloading on the interface.
325Some drivers may not be able to enable these flags independently
326of each other, so setting one may also set the other.
327The driver will offload as much checksum work as it can reliably
328support, the exact level of offloading varies between drivers.
329.\".It Fl rxcsum , Fl txcsum
330.\"If the driver supports user-configurable checksum offloading,
331.\"disable receive (or transmit) checksum offloading on the interface.
332.\"These settings may not always be independent of each other.
333.\".It Cm polling
334.\"If the driver has user-configurable
335.\".Xr polling 4
336.\"support, select the polling mode on the interface.
337.\".It Fl polling
338.\"If the driver has user-configurable
339.\".Xr polling 4
340.\"support, select the interrupt mode on the interface.
341.It Cm tunnel Ar src_addr dest_addr
342(IP tunnel devices only.)
343Configure the physical source and destination address for IP tunnel
344interfaces
345.Pq Xr gif 4 .
346The arguments
347.Ar src_addr
348and
349.Ar dest_addr
350are interpreted as the outer source/destination for the encapsulating
351IPv4/IPv6 header.
352.It Cm deletetunnel
353Unconfigure the physical source and destination address for IP tunnel
354interfaces previously configured with
355.Cm tunnel .
356.It Cm create
357Create the specified network pseudo-device.
358If the interface is given without a unit number, try to create a new
359device with an arbitrary unit number.
360If creation of an arbitrary device is successful, the new device name is
361printed to standard output.
362.It Cm destroy
363Destroy the specified network pseudo-device.
364.It Cm plumb
365Another name for the
366.Cm create
367parameter.
368Included for
369.Tn Solaris
370compatibility.
371.It Cm unplumb
372Another name for the
373.Cm destroy
374parameter.
375Included for
376.Tn Solaris
377compatibility.
378.It Cm vlan Ar vlan_tag
379If the interface is a
380.Xr vlan 4
381pseudo interface, set the VLAN tag value
382to
383.Ar vlan_tag .
384This value is a 16-bit number which is used to create an 802.1Q
385VLAN header for packets sent from the
386.Xr vlan 4
387interface.
388Note that
389.Cm vlan
390and
391.Cm vlandev
392must both be set at the same time.
393.It Cm vlandev Ar iface
394If the interface is a
395.Xr vlan 4
396pseudo device, associate physical interface
397.Ar iface
398with it.
399Packets transmitted through the
400.Xr vlan 4
401interface will be
402diverted to the specified physical interface
403.Ar iface
404with 802.1Q VLAN encapsulation.
405Packets with 802.1Q encapsulation received
406by the parent interface with the correct VLAN tag will be diverted to
407the associated
408.Xr vlan 4
409pseudo-interface.
410The
411.Xr vlan 4
412interface is assigned a
413copy of the parent interface's flags and the parent's ethernet address.
414The
415.Cm vlandev
416and
417.Cm vlan
418must both be set at the same time.
419If the
420.Xr vlan 4
421interface already has
422a physical interface associated with it, this command will fail.
423To
424change the association to another physical interface, the existing
425association must be cleared first.
426.Pp
427Note: if the hardware tagging capability
428is set on the parent interface, the
429.Xr vlan 4
430pseudo
431interface's behavior changes:
432the
433.Xr vlan 4
434interface recognizes that the
435parent interface supports insertion and extraction of VLAN tags on its
436own (usually in firmware) and that it should pass packets to and from
437the parent unaltered.
438.It Fl vlandev Ar iface
439If the driver is a
440.Xr vlan 4
441pseudo device, disassociate the physical interface
442.Ar iface
443from it.
444This breaks the link between the
445.Xr vlan 4
446interface and its parent,
447clears its VLAN tag, flags and its link address and shuts the interface down.
448.It Cm vlanmtu , vlanhwtag
449If the driver offers user-configurable VLAN support, enable
450reception of extended frames or tag processing in hardware,
451respectively.
452Note that this must be issued on a physical interface associated with
453.Xr vlan 4 ,
454not on a
455.Xr vlan 4
456interface itself.
457.It Fl vlanmtu , Fl vlanhwtag
458If the driver offers user-configurable VLAN support, disable
459reception of extended frames or tag processing in hardware,
460respectively.
461.It Cm metric Ar n
462Set the routing metric of the interface to
463.Ar n ,
464default 0.
465The routing metric is used by the routing protocol
466.Pq Xr routed 8 .
467Higher metrics have the effect of making a route
468less favorable; metrics are counted as addition hops
469to the destination network or host.
470.It Cm mtu Ar n
471Set the maximum transmission unit of the interface to
472.Ar n ,
473default is interface specific.
474The MTU is used to limit the size of packets that are transmitted on an
475interface.
476Not all interfaces support setting the MTU, and some interfaces have
477range restrictions.
478.It Cm netmask Ar mask
479.\" (Inet and ISO.)
480(Inet only.)
481Specify how much of the address to reserve for subdividing
482networks into sub-networks.
483The mask includes the network part of the local address
484and the subnet part, which is taken from the host field of the address.
485The mask can be specified as a single hexadecimal number
486with a leading
487.Ql 0x ,
488with a dot-notation Internet address,
489or with a pseudo-network name listed in the network table
490.Xr networks 5 .
491The mask contains 1's for the bit positions in the 32-bit address
492which are to be used for the network and subnet parts,
493and 0's for the host part.
494The mask should contain at least the standard network portion,
495and the subnet field should be contiguous with the network
496portion.
497.Pp
498The netmask can also be specified in CIDR notation after the address.
499See the
500.Ar address
501option above for more information.
502.It Cm prefixlen Ar len
503(Inet6 only.)
504Specify that
505.Ar len
506bits are reserved for subdividing networks into sub-networks.
507The
508.Ar len
509must be integer, and for syntactical reason it must be between 0 to 128.
510It is almost always 64 under the current IPv6 assignment rule.
511If the parameter is omitted, 64 is used.
512.Pp
513The prefix can also be specified using the slash notation after the address.
514See the
515.Ar address
516option above for more information.
517.\" see
518.\" Xr eon 5 .
519.\" .It Cm nsellength Ar n
520.\" .Pf ( Tn ISO
521.\" only)
522.\" This specifies a trailing number of bytes for a received
523.\" .Tn NSAP
524.\" used for local identification, the remaining leading part of which is
525.\" taken to be the
526.\" .Tn NET
527.\" (Network Entity Title).
528.\" The default value is 1, which is conformant to US
529.\" .Tn GOSIP .
530.\" When an ISO address is set in an ifconfig command,
531.\" it is really the
532.\" .Tn NSAP
533.\" which is being specified.
534.\" For example, in
535.\" .Tn US GOSIP ,
536.\" 20 hex digits should be
537.\" specified in the
538.\" .Tn ISO NSAP
539.\" to be assigned to the interface.
540.\" There is some evidence that a number different from 1 may be useful
541.\" for
542.\" .Tn AFI
543.\" 37 type addresses.
544.It Cm range Ar netrange
545Under appletalk, set the interface to respond to a
546.Ar netrange
547of the form
548.Ar startnet Ns - Ns Ar endnet .
549Appletalk uses this scheme instead of
550netmasks though
551.Fx
552implements it internally as a set of netmasks.
553.It Cm remove
554Another name for the
555.Fl alias
556parameter.
557Introduced for compatibility
558with
559.Bsx .
560.It Cm phase
561The argument following this specifies the version (phase) of the
562Appletalk network attached to the interface.
563Values of 1 or 2 are permitted.
564.Sm off
565.It Cm link Op Cm 0 No - Cm 2
566.Sm on
567Enable special processing of the link level of the interface.
568These three options are interface specific in actual effect, however,
569they are in general used to select special modes of operation.
570An example
571of this is to enable SLIP compression, or to select the connector type
572for some Ethernet cards.
573Refer to the man page for the specific driver
574for more information.
575.Sm off
576.It Fl link Op Cm 0 No - Cm 2
577.Sm on
578Disable special processing at the link level with the specified interface.
579.\".It Cm monitor
580.\"Put the interface in monitor mode.
581.\"No packets are transmitted, and received packets are discarded after
582.\".Xr bpf 4
583.\"processing.
584.\".It Fl monitor
585.\"Take the interface out of monitor mode.
586.It Cm up
587Mark an interface
588.Dq up .
589This may be used to enable an interface after an
590.Dq Nm Cm down .
591It happens automatically when setting the first address on an interface.
592If the interface was reset when previously marked down,
593the hardware will be re-initialized.
594.It Cm ssid Ar ssid
595For IEEE 802.11 wireless interfaces, set the desired Service Set
596Identifier (aka network name).
597The SSID is a string up to 32 characters
598in length and may be specified as either a normal string or in
599hexadecimal when proceeded by
600.Ql 0x .
601Additionally, the SSID may be cleared by setting it to
602.Ql - .
603.It Cm nwid Ar ssid
604Another name for the
605.Cm ssid
606parameter.
607Included for
608.Nx
609compatibility.
610.It Cm stationname Ar name
611For IEEE 802.11 wireless interfaces, set the name of this station.
612It appears that the station name is not really part of the IEEE 802.11
613protocol though all interfaces seem to support it.
614As such it only
615seems to be meaningful to identical or virtually identical equipment.
616Setting the station name is identical in syntax to setting the SSID.
617.It Cm station Ar name
618Another name for the
619.Cm stationname
620parameter.
621Included for
622.Bsx
623compatibility.
624.It Cm channel Ar number
625For IEEE 802.11 wireless interfaces, set the desired channel.
626Channels range from 1 to 14, but the exact selection available
627depends on the region your adaptor was manufactured for.
628Setting
629the channel to 0 will give you the default for your adaptor.
630Many
631adaptors ignore this setting unless you are in ad-hoc mode.
632.It Cm authmode Ar mode
633For IEEE 802.11 wireless interfaces, set the desired authentication mode
634in infrastructure mode.
635Not all adaptors support all modes.
636The set of
637valid modes is
638.Dq Li none ,
639.Dq Li open ,
640and
641.Dq Li shared .
642Modes are case insensitive.
643.It Cm powersave
644For IEEE 802.11 wireless interfaces, enable powersave mode.
645.It Fl powersave
646For IEEE 802.11 wireless interfaces, disable powersave mode.
647.It Cm powersavesleep Ar sleep
648For IEEE 802.11 wireless interfaces, set the desired max powersave sleep
649time in milliseconds.
650.It Cm protmode Ar technique
651For IEEE 802.11 wireless interfaces operating in 11g, use the specified
652.Ar technique
653for protecting OFDM frames in a mixed 11b/11g network.
654The set of valid techniques is
655.Dq Li off ,
656.Dq Li cts
657(CTS to self),
658and
659.Dq Li rtscts
660(RTS/CTS).
661Technique names are case insensitive.
662.It Cm rtsthreshold Ar length
663For IEEE 802.11 wireless interfaces, set the threshold for which
664transmitted frames are preceded by transmission of an
665RTS
666control frame.
667The
668.Ar length
669argument
670is the frame size in bytes and must be in the range 1 to 2312.
671Not all adaptors support setting the RTS threshold.
672.It Cm txpower Ar power
673For IEEE 802.11 wireless interfaces, set the power used to transmit frames.
674The
675.Ar power
676argument
677is a unitless value in the range 0 to 100 that is interpreted
678by drivers to derive a device-specific value.
679Out of range values are truncated.
680Typically only a few discreet power settings are available and
681the driver will use the setting closest to the specified value.
682Not all adaptors support changing the transmit power.
683.It Cm wepmode Ar mode
684For IEEE 802.11 wireless interfaces, set the desired WEP mode.
685Not all adaptors support all modes.
686The set of valid modes is
687.Dq Li off ,
688.Dq Li on ,
689and
690.Dq Li mixed .
691The
692.Dq Li mixed
693mode explicitly tells the adaptor to allow association with access
694points which allow both encrypted and unencrypted traffic.
695On these adaptors,
696.Dq Li on
697means that the access point must only allow encrypted connections.
698On other adaptors,
699.Dq Li on
700is generally another name for
701.Dq Li mixed .
702Modes are case insensitive.
703.It Cm weptxkey Ar index
704For IEEE 802.11 wireless interfaces, set the WEP key to be used for
705transmission.
706.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key
707For IEEE 802.11 wireless interfaces, set the selected WEP key.
708If an
709.Ar index
710is not given, key 1 is set.
711A WEP key will be either 5 or 13
712characters (40 or 104 bits) depending of the local network and the
713capabilities of the adaptor.
714It may be specified either as a plain
715string or as a string of hexadecimal digits proceeded by
716.Ql 0x .
717For maximum portability, hex keys are recommended;
718the mapping of text keys to WEP encryption is usually driver-specific.
719In particular, the
720.Tn Windows
721drivers do this mapping differently to
722.Fx .
723A key may be cleared by setting it to
724.Ql - .
725If WEP is supported then there are at least four keys.
726Some adaptors support more than four keys.
727If that is the case, then the first four keys
728(1-4) will be the standard temporary keys and any others will be adaptor
729specific keys such as permanent keys stored in NVRAM.
730.It Cm wep
731Another way of saying
732.Cm wepmode on .
733Included for
734.Bsx
735compatibility.
736.It Fl wep
737Another way of saying
738.Cm wepmode off .
739Included for
740.Bsx
741compatibility.
742.It Cm nwkey key
743Another way of saying:
744.Pp
745.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" .
746.Pp
747Included for
748.Nx
749compatibility.
750.It Cm nwkey Xo
751.Sm off
752.Ar n : k1 , k2 , k3 , k4
753.Sm on
754.Xc
755Another way of saying
756.Pp
757.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" .
758.Pp
759Included for
760.Nx
761compatibility.
762.It Fl nwkey
763Another way of saying
764.Cm wepmode off .
765.Pp
766Included for
767.Nx
768compatibility.
769.El
770.Pp
771The
772.Nm
773utility displays the current configuration for a network interface
774when no optional parameters are supplied.
775If a protocol family is specified,
776.Nm
777will report only the details specific to that protocol family.
778.Pp
779If the driver does supports the media selection system, the supported
780media list will be included in the output.
781.Pp
782If the
783.Fl m
784flag is passed before an interface name,
785.Nm
786will display the capability list and all
787of the supported media for the specified interface.
788If
789.Fl L
790flag is supplied, address lifetime is displayed for IPv6 addresses,
791as time offset string.
792.Pp
793Optionally, the
794.Fl a
795flag may be used instead of an interface name.
796This flag instructs
797.Nm
798to display information about all interfaces in the system.
799The
800.Fl d
801flag limits this to interfaces that are down, and
802.Fl u
803limits this to interfaces that are up.
804When no arguments are given,
805.Fl a
806is implied.
807.Pp
808The
809.Fl l
810flag may be used to list all available interfaces on the system, with
811no other additional information.
812Use of this flag is mutually exclusive
813with all other flags and commands, except for
814.Fl d
815(only list interfaces that are down)
816and
817.Fl u
818(only list interfaces that are up).
819.Pp
820The
821.Fl C
822flag may be used to list all of the interface cloners available on
823the system, with no additional information.
824Use of this flag is mutually exclusive with all other flags and commands.
825.Pp
826Only the super-user may modify the configuration of a network interface.
827.Sh NOTES
828The media selection system is relatively new and only some drivers support
829it (or have need for it).
830.Sh DIAGNOSTICS
831Messages indicating the specified interface does not exist, the
832requested address is unknown, or the user is not privileged and
833tried to alter an interface's configuration.
834.Sh BUGS
835Basic IPv6 node operation requires a link-local address on each
836interface configured for IPv6.
837Normally, such an address is automatically configured by the
838kernel on each interface added to the system; this behaviour may
839be disabled by setting the sysctl MIB variable
840.Va net.inet6.ip6.auto_linklocal
841to 0.
842.Pp
843If you delete such an address using
844.Nm ,
845the kernel may act very oddly.
846Do this at your own risk.
847.Sh SEE ALSO
848.Xr netstat 1 ,
849.Xr netintro 4 ,
850.Xr vlan 4 ,
851.\" .Xr eon 5 ,
852.Xr rc 8 ,
853.Xr routed 8 ,
854.Xr sysctl 8
855.Sh HISTORY
856The
857.Nm
858utility appeared in
859.Bx 4.2 .