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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgment: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" From: @(#)ifconfig.8 8.3 (Berkeley) 1/5/94 33.\" $FreeBSD$ 34.\" 35.Dd July 2, 2001 36.Dt IFCONFIG 8 37.Os 38.Sh NAME 39.Nm ifconfig 40.Nd configure network interface parameters 41.Sh SYNOPSIS 42.Nm 43.Op Fl L 44.Op Fl m 45.Ar interface 46.Op Cm create 47.Op Ar address_family 48.Oo 49.Ar address 50.Op Ar dest_address 51.Oc 52.Op Ar parameters 53.Nm 54.Ar interface 55.Cm destroy 56.Nm 57.Fl a 58.Op Fl L 59.Op Fl d 60.Op Fl m 61.Op Fl u 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 m 72.Op Fl u 73.Op Fl C 74.Sh DESCRIPTION 75The 76.Nm 77utility is used to assign an address 78to a network interface and/or configure 79network interface parameters. 80The 81.Nm 82utility must be used at boot time to define the network address 83of each interface present on a machine; it may also be used at 84a later time to redefine an interface's address 85or other operating parameters. 86.Pp 87The following options are available: 88.Bl -tag -width indent 89.It Ar address 90For the 91.Tn DARPA Ns -Internet 92family, 93the address is either a host name present in the host name data 94base, 95.Xr hosts 5 , 96or a 97.Tn DARPA 98Internet address expressed in the Internet standard 99.Dq dot notation . 100.Pp 101It is also possible to use the CIDR notation (also known as the 102slash notation) to include the netmask. 103That is, one can specify an address like 104.Li 192.168.0.1/16 . 105.Pp 106For 107.Dq inet6 108family, it is also possible to specify the prefix length using the slash 109notation, like 110.Li ::1/128 . 111See the 112.Cm prefixlen 113parameter below for more information. 114.\" For the Xerox Network Systems(tm) family, 115.\" addresses are 116.\" .Ar net:a.b.c.d.e.f , 117.\" where 118.\" .Ar net 119.\" is the assigned network number (in decimal), 120.\" and each of the six bytes of the host number, 121.\" .Ar a 122.\" through 123.\" .Ar f , 124.\" are specified in hexadecimal. 125.\" The host number may be omitted on IEEE 802 protocol 126.\" (Ethernet, FDDI, and Token Ring) interfaces, 127.\" which use the hardware physical address, 128.\" and on interfaces other than the first. 129.\" For the 130.\" .Tn ISO 131.\" family, addresses are specified as a long hexadecimal string, 132.\" as in the Xerox family. 133.\" However, two consecutive dots imply a zero 134.\" byte, and the dots are optional, if the user wishes to (carefully) 135.\" count out long strings of digits in network byte order. 136.Pp 137The link-level 138.Pq Dq link 139address 140is specified as a series of colon-separated hex digits. 141This can be used to 142e.g. set a new MAC address on an ethernet interface, though the 143mechanism used is not ethernet-specific. 144If the interface is already 145up when this option is used, it will be briefly brought down and 146then brought back up again in order to ensure that the receive 147filter in the underlying ethernet hardware is properly reprogrammed. 148.It Ar address_family 149Specify the 150address family 151which affects interpretation of the remaining parameters. 152Since an interface can receive transmissions in differing protocols 153with different naming schemes, specifying the address family is recommended. 154The address or protocol families currently 155supported are 156.Dq inet , 157.Dq inet6 , 158.Dq atalk , 159.Dq ipx , 160.\" .Dq iso , 161and 162.Dq link . 163.\" and 164.\" .Dq ns . 165The default is 166.Dq inet . 167.Dq ether 168and 169.Dq lladdr 170are synonyms for 171.Dq link . 172.It Ar dest_address 173Specify the address of the correspondent on the other end 174of a point to point link. 175.It Ar interface 176This 177parameter is a string of the form 178.Dq name unit , 179for example, 180.Dq Li ed0 . 181.El 182.Pp 183The following parameters may be set with 184.Nm : 185.Bl -tag -width indent 186.It Cm add 187Another name for the 188.Cm alias 189parameter. 190Introduced for compatibility 191with 192.Bsx . 193.It Cm alias 194Establish an additional network address for this interface. 195This is sometimes useful when changing network numbers, and 196one wishes to accept packets addressed to the old interface. 197If the address is on the same subnet as the first network address 198for this interface, a non-conflicting netmask must be given. 199Usually 200.Li 0xffffffff 201is most appropriate. 202.It Fl alias 203Remove the network address specified. 204This would be used if you incorrectly specified an alias, or it 205was no longer needed. 206If you have incorrectly set an NS address having the side effect 207of specifying the host portion, removing all NS addresses will 208allow you to respecify the host portion. 209.It Cm anycast 210(Inet6 only.) 211Specify that the address configured is an anycast address. 212Based on the current specification, 213only routers may configure anycast addresses. 214Anycast address will not be used as source address of any of outgoing 215IPv6 packets. 216.It Cm arp 217Enable the use of the Address Resolution Protocol 218.Pq Xr arp 4 219in mapping 220between network level addresses and link level addresses (default). 221This is currently implemented for mapping between 222.Tn DARPA 223Internet 224addresses and 225.Tn IEEE 226802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). 227.It Fl arp 228Disable the use of the Address Resolution Protocol 229.Pq Xr arp 4 . 230.It Cm broadcast 231(Inet only.) 232Specify the address to use to represent broadcasts to the 233network. 234The default broadcast address is the address with a host part of all 1's. 235.It Cm debug 236Enable driver dependent debugging code; usually, this turns on 237extra console error logging. 238.It Fl debug 239Disable driver dependent debugging code. 240.It Cm promisc 241Put interface into permanently promiscuous mode. 242.It Fl promisc 243Disable permanently promiscuous mode. 244.It Cm delete 245Another name for the 246.Fl alias 247parameter. 248.It Cm down 249Mark an interface 250.Dq down . 251When an interface is marked 252.Dq down , 253the system will not attempt to 254transmit messages through that interface. 255If possible, the interface will be reset to disable reception as well. 256This action does not automatically disable routes using the interface. 257.It Cm eui64 258(Inet6 only.) 259Fill interface index 260(lowermost 64bit of an IPv6 address) 261automatically. 262.\" .It Cm ipdst 263.\" This is used to specify an Internet host who is willing to receive 264.\" ip packets encapsulating NS packets bound for a remote network. 265.\" An apparent point to point link is constructed, and 266.\" the address specified will be taken as the NS address and network 267.\" of the destination. 268.\" IP encapsulation of 269.\" .Tn CLNP 270.\" packets is done differently. 271.It Cm media Ar type 272If the driver supports the media selection system, set the media type 273of the interface to 274.Ar type . 275Some interfaces support the mutually exclusive use of one of several 276different physical media connectors. 277For example, a 10Mb/s Ethernet 278interface might support the use of either 279.Tn AUI 280or twisted pair connectors. 281Setting the media type to 282.Dq 10base5/AUI 283would change the currently active connector to the AUI port. 284Setting it to 285.Dq 10baseT/UTP 286would activate twisted pair. 287Refer to the interfaces' driver 288specific documentation or man page for a complete list of the 289available types. 290.It Cm mediaopt Ar opts 291If the driver supports the media selection system, set the specified 292media options on the interface. 293The 294.Ar opts 295argument 296is a comma delimited list of options to apply to the interface. 297Refer to the interfaces' driver specific man page for a complete 298list of available options. 299.It Fl mediaopt Ar opts 300If the driver supports the media selection system, disable the 301specified media options on the interface. 302.It Cm tunnel Ar src_addr dest_addr 303(IP tunnel devices only.) 304Configure the physical source and destination address for IP tunnel 305interfaces 306.Pq Xr gif 4 . 307The arguments 308.Ar src_addr 309and 310.Ar dest_addr 311are interpreted as the outer source/destination for the encapsulating 312IPv4/IPv6 header. 313.It Cm deletetunnel 314Unconfigure the physical source and destination address for IP tunnel 315interfaces previously configured with 316.Cm tunnel . 317.It Cm create 318Create the specified network pseudo-device. 319If the interface is given without a unit number, try to create a new 320device with an arbitrary unit number. 321If creation of an arbitrary device is successful, the new device name is 322printed to standard output. 323.It Cm destroy 324Destroy the specified network pseudo-device. 325.It Cm plumb 326Another name for the 327.Cm create 328parameter. 329Included for 330.Tn Solaris 331compatibility. 332.It Cm unplumb 333Another name for the 334.Cm destroy 335parameter. 336Included for 337.Tn Solaris 338compatibility. 339.It Cm vlan Ar vlan_tag 340If the interface is a vlan pseudo interface, set the vlan tag value 341to 342.Ar vlan_tag . 343This value is a 16-bit number which is used to create an 802.1Q 344vlan header for packets sent from the vlan interface. 345Note that 346.Cm vlan 347and 348.Cm vlandev 349must both be set at the same time. 350.It Cm vlandev Ar iface 351If the interface is a vlan pseudo device, associate physical interface 352.Ar iface 353with it. 354Packets transmitted through the vlan interface will be 355diverted to the specified physical interface 356.Ar iface 357with 802.1Q vlan encapsulation. 358Packets with 802.1Q encapsulation received 359by the parent interface with the correct vlan tag will be diverted to 360the associated vlan pseudo-interface. 361The vlan interface is assigned a 362copy of the parent interface's flags and the parent's ethernet address. 363The 364.Cm vlandev 365and 366.Cm vlan 367must both be set at the same time. 368If the vlan interface already has 369a physical interface associated with it, this command will fail. 370To 371change the association to another physical interface, the existing 372association must be cleared first. 373.Pp 374Note: if the 375.Cm link0 376flag is set on the vlan interface, the vlan pseudo 377interface's behavior changes: the 378.Cm link0 379tells the vlan interface that the 380parent interface supports insertion and extraction of vlan tags on its 381own (usually in firmware) and that it should pass packets to and from 382the parent unaltered. 383.It Fl vlandev Ar iface 384If the driver is a vlan pseudo device, disassociate the physical interface 385.Ar iface 386from it. 387This breaks the link between the vlan interface and its parent, 388clears its vlan tag, flags and its link address and shuts the interface down. 389.It Cm metric Ar n 390Set the routing metric of the interface to 391.Ar n , 392default 0. 393The routing metric is used by the routing protocol 394.Pq Xr routed 8 . 395Higher metrics have the effect of making a route 396less favorable; metrics are counted as addition hops 397to the destination network or host. 398.It Cm mtu Ar n 399Set the maximum transmission unit of the interface to 400.Ar n , 401default is interface specific. 402The MTU is used to limit the size of packets that are transmitted on an 403interface. 404Not all interfaces support setting the MTU, and some interfaces have 405range restrictions. 406.It Cm netmask Ar mask 407.\" (Inet and ISO.) 408(Inet only.) 409Specify how much of the address to reserve for subdividing 410networks into sub-networks. 411The mask includes the network part of the local address 412and the subnet part, which is taken from the host field of the address. 413The mask can be specified as a single hexadecimal number 414with a leading 415.Ql 0x , 416with a dot-notation Internet address, 417or with a pseudo-network name listed in the network table 418.Xr networks 5 . 419The mask contains 1's for the bit positions in the 32-bit address 420which are to be used for the network and subnet parts, 421and 0's for the host part. 422The mask should contain at least the standard network portion, 423and the subnet field should be contiguous with the network 424portion. 425.Pp 426The netmask can also be specified in CIDR notation after the address. 427See the 428.Ar address 429option above for more information. 430.It Cm prefixlen Ar len 431(Inet6 only.) 432Specify that 433.Ar len 434bits are reserved for subdividing networks into sub-networks. 435The 436.Ar len 437must be integer, and for syntactical reason it must be between 0 to 128. 438It is almost always 64 under the current IPv6 assignment rule. 439If the parameter is omitted, 64 is used. 440.Pp 441The prefix can also be specified using the slash notation after the address. 442See the 443.Ar address 444option above for more information. 445.\" see 446.\" Xr eon 5 . 447.\" .It Cm nsellength Ar n 448.\" .Pf ( Tn ISO 449.\" only) 450.\" This specifies a trailing number of bytes for a received 451.\" .Tn NSAP 452.\" used for local identification, the remaining leading part of which is 453.\" taken to be the 454.\" .Tn NET 455.\" (Network Entity Title). 456.\" The default value is 1, which is conformant to US 457.\" .Tn GOSIP . 458.\" When an ISO address is set in an ifconfig command, 459.\" it is really the 460.\" .Tn NSAP 461.\" which is being specified. 462.\" For example, in 463.\" .Tn US GOSIP , 464.\" 20 hex digits should be 465.\" specified in the 466.\" .Tn ISO NSAP 467.\" to be assigned to the interface. 468.\" There is some evidence that a number different from 1 may be useful 469.\" for 470.\" .Tn AFI 471.\" 37 type addresses. 472.It Cm range Ar netrange 473Under appletalk, set the interface to respond to a 474.Ar netrange 475of the form 476.Ar startnet Ns - Ns Ar endnet . 477Appletalk uses this scheme instead of 478netmasks though 479.Fx 480implements it internally as a set of netmasks. 481.It Cm remove 482Another name for the 483.Fl alias 484parameter. 485Introduced for compatibility 486with 487.Bsx . 488.It Cm phase 489The argument following this specifies the version (phase) of the 490Appletalk network attached to the interface. 491Values of 1 or 2 are permitted. 492.Sm off 493.It Cm link Op Cm 0 No - Cm 2 494.Sm on 495Enable special processing of the link level of the interface. 496These three options are interface specific in actual effect, however, 497they are in general used to select special modes of operation. 498An example 499of this is to enable SLIP compression, or to select the connector type 500for some Ethernet cards. 501Refer to the man page for the specific driver 502for more information. 503.Sm off 504.It Fl link Op Cm 0 No - Cm 2 505.Sm on 506Disable special processing at the link level with the specified interface. 507.It Cm monitor 508.Sm on 509Put the interface in monitor mode. 510No packets are transmitted and received packets are discarded after 511.Xr bpf 4 512processing. 513.Sm off 514.It Fl monitor 515.Sm on 516Take the interface out of monitor mode. 517.Sm off 518.It Cm up 519Mark an interface 520.Dq up . 521This may be used to enable an interface after an 522.Dq Nm Cm down . 523It happens automatically when setting the first address on an interface. 524If the interface was reset when previously marked down, 525the hardware will be re-initialized. 526.It Cm ssid Ar ssid 527For IEEE 802.11 wireless interfaces, set the desired Service Set 528Identifier (aka network name). 529The SSID is a string up to 32 characters 530in length and may be specified as either a normal string or in 531hexadecimal when proceeded by 532.Ql 0x . 533Additionally, the SSID may be cleared by setting it to 534.Ql - . 535.It Cm nwid Ar ssid 536Another name for the 537.Cm ssid 538parameter. 539Included for 540.Nx 541compatibility. 542.It Cm stationname Ar name 543For IEEE 802.11 wireless interfaces, set the name of this station. 544It appears that the station name is not really part of the IEEE 802.11 545protocol though all interfaces seem to support it. 546As such it only 547seems to be meaningful to identical or virtually identical equipment. 548Setting the station name is identical in syntax to setting the SSID. 549.It Cm station Ar name 550Another name for the 551.Cm stationname 552parameter. 553Included for 554.Bsx 555compatibility. 556.It Cm channel Ar number 557For IEEE 802.11 wireless interfaces, set the desired channel. 558Channels range from 1 to 14, but the exact selection available 559depends on the region your adaptor was manufactured for. 560Setting 561the channel to 0 will give you the default for your adaptor. 562Many 563adaptors ignore this setting unless you are in ad-hoc mode. 564.It Cm authmode Ar mode 565For IEEE 802.11 wireless interfaces, set the desired authentication mode 566in infrastructure mode. 567Not all adaptors support all modes. 568The set of 569valid modes is 570.Dq none , 571.Dq open , 572and 573.Dq shared . 574Modes are case insensitive. 575.It Cm powersave 576For IEEE 802.11 wireless interfaces, enable powersave mode. 577.It Fl powersave 578For IEEE 802.11 wireless interfaces, disable powersave mode. 579.It Cm powersavesleep Ar sleep 580For IEEE 802.11 wireless interfaces, set the desired max powersave sleep 581time in milliseconds. 582.It Cm wepmode Ar mode 583For IEEE 802.11 wireless interfaces, set the desired WEP mode. 584Not all adaptors support all modes. 585The set of valid modes is 586.Dq off , 587.Dq on , 588and 589.Dq mixed . 590.Dq Mixed 591mode explicitly tells the adaptor to allow association with access 592points which allow both encrypted and unencrypted traffic. 593On these adaptors, 594.Dq on 595means that the access point must only allow encrypted connections. 596On other adaptors, 597.Dq on 598is generally another name for 599.Dq mixed . 600Modes are case insensitive. 601.It Cm weptxkey Ar index 602For IEEE 802.11 wireless interfaces, set the WEP key to be used for 603transmission. 604.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 605For IEEE 802.11 wireless interfaces, set the selected WEP key. 606If an 607.Ar index 608is not given, key 1 is set. 609A WEP key will be either 5 or 13 610characters (40 or 104 bits) depending of the local network and the 611capabilities of the adaptor. 612It may be specified either as a plain 613string or as a string of hexadecimal digits proceeded by 614.Ql 0x . 615For maximum portability, hex keys are recommended; 616the mapping of text keys to WEP encryption is usually driver-specific. 617In particular, the Windows drivers do this mapping differently to 618.Fx . 619A key may be cleared by setting it to 620.Ql - . 621If WEP is supported then there are at least four keys. 622Some adaptors support more than four keys. 623If that is the case, then the first four keys 624(1-4) will be the standard temporary keys and any others will be adaptor 625specific keys such as permanent keys stored in NVRAM. 626.It Cm wep 627Another way of saying 628.Cm wepmode on . 629Included for 630.Bsx 631compatibility. 632.It Fl wep 633Another way of saying 634.Cm wepmode off . 635Included for 636.Bsx 637compatibility. 638.It Cm nwkey key 639Another way of saying: 640.Pp 641.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 642.Pp 643Included for 644.Nx 645compatibility. 646.It Cm nwkey Xo 647.Sm off 648.Ar n : k1 , k2 , k3 , k4 649.Sm on 650.Xc 651Another way of saying 652.Pp 653.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 654.Pp 655Included for 656.Nx 657compatibility. 658.It Fl nwkey 659Another way of saying 660.Cm wepmode off . 661.Pp 662Included for 663.Nx 664compatibility. 665.El 666.Pp 667The 668.Nm 669utility displays the current configuration for a network interface 670when no optional parameters are supplied. 671If a protocol family is specified, 672.Nm 673will report only the details specific to that protocol family. 674.Pp 675If the driver does supports the media selection system, the supported 676media list will be included in the output. 677.Pp 678If the 679.Fl m 680flag is passed before an interface name, 681.Nm 682will display all 683of the supported media for the specified interface. 684If 685.Fl L 686flag is supplied, address lifetime is displayed for IPv6 addresses, 687as time offset string. 688.Pp 689Optionally, the 690.Fl a 691flag may be used instead of an interface name. 692This flag instructs 693.Nm 694to display information about all interfaces in the system. 695The 696.Fl d 697flag limits this to interfaces that are down, and 698.Fl u 699limits this to interfaces that are up. 700When no arguments are given, 701.Fl a 702is implied. 703.Pp 704The 705.Fl l 706flag may be used to list all available interfaces on the system, with 707no other additional information. 708Use of this flag is mutually exclusive 709with all other flags and commands, except for 710.Fl d 711(only list interfaces that are down) 712and 713.Fl u 714(only list interfaces that are up). 715.Pp 716The 717.Fl C 718flag may be used to list all of the interface cloners available on 719the system, with no additional information. 720Use of this flag is mutually exclusive with all other flags and commands. 721.Pp 722Only the super-user may modify the configuration of a network interface. 723.Sh NOTES 724The media selection system is relatively new and only some drivers support 725it (or have need for it). 726.Sh DIAGNOSTICS 727Messages indicating the specified interface does not exist, the 728requested address is unknown, or the user is not privileged and 729tried to alter an interface's configuration. 730.Sh BUGS 731IPv6 link-local addresses are required for several basic communication 732between IPv6 node. 733If they are deleted by 734.Nm 735manually, the kernel might show very strange behavior. 736So, such manual deletions are strongly discouraged. 737.Sh SEE ALSO 738.Xr netstat 1 , 739.Xr netintro 4 , 740.\" .Xr eon 5 , 741.Xr rc 8 , 742.Xr routed 8 743.Sh HISTORY 744The 745.Nm 746utility appeared in 747.Bx 4.2 . 748