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 Ns Op Cm / Ns Ar prefixlength 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 75.Nm Ifconfig 76is used to assign an address 77to a network interface and/or configure 78network interface parameters. 79.Nm Ifconfig 80must be used at boot time to define the network address 81of each interface present on a machine; it may also be used at 82a later time to redefine an interface's address 83or other operating parameters. 84.Pp 85The following options are available: 86.Bl -tag -width indent 87.It Ar address 88For the 89.Tn DARPA Ns -Internet 90family, 91the address is either a host name present in the host name data 92base, 93.Xr hosts 5 , 94or a 95.Tn DARPA 96Internet address expressed in the Internet standard 97.Dq dot notation . 98.Pp 99It is also possible to use the CIDR notation (also known as the 100slash notation) to include the netmask. 101That is, one can specify an address like 102.Li 192.168.0.1/16 . 103.\" For the Xerox Network Systems(tm) family, 104.\" addresses are 105.\" .Ar net:a.b.c.d.e.f , 106.\" where 107.\" .Ar net 108.\" is the assigned network number (in decimal), 109.\" and each of the six bytes of the host number, 110.\" .Ar a 111.\" through 112.\" .Ar f , 113.\" are specified in hexadecimal. 114.\" The host number may be omitted on IEEE 802 protocol 115.\" (Ethernet, FDDI, and Token Ring) interfaces, 116.\" which use the hardware physical address, 117.\" and on interfaces other than the first. 118.\" For the 119.\" .Tn ISO 120.\" family, addresses are specified as a long hexadecimal string, 121.\" as in the Xerox family. 122.\" However, two consecutive dots imply a zero 123.\" byte, and the dots are optional, if the user wishes to (carefully) 124.\" count out long strings of digits in network byte order. 125.It Ar address_family 126Specify the 127address family 128which affects interpretation of the remaining parameters. 129Since an interface can receive transmissions in differing protocols 130with different naming schemes, specifying the address family is recommended. 131The address or protocol families currently 132supported are 133.Dq inet , 134.Dq inet6 , 135.Dq atalk , 136.Dq ether , 137.\" .Dq iso , 138and 139.Dq ipx . 140.\" and 141.\" .Dq ns . 142.It Ar dest_address 143Specify the address of the correspondent on the other end 144of a point to point link. 145.It Ar interface 146This 147parameter is a string of the form 148.Dq name unit , 149for example, 150.Dq Li ed0 . 151.El 152.Pp 153The following parameters may be set with 154.Nm : 155.Bl -tag -width indent 156.It Cm add 157Another name for the 158.Cm alias 159parameter. 160Introduced for compatibility 161with 162.Bsx . 163.It Cm alias 164Establish an additional network address for this interface. 165This is sometimes useful when changing network numbers, and 166one wishes to accept packets addressed to the old interface. 167If the address is on the same subnet as the first network address 168for this interface, a netmask of 169.Li 0xffffffff 170has to be specified. 171.It Fl alias 172Remove the network address specified. 173This would be used if you incorrectly specified an alias, or it 174was no longer needed. 175If you have incorrectly set an NS address having the side effect 176of specifying the host portion, removing all NS addresses will 177allow you to respecify the host portion. 178.It Cm anycast 179(Inet6 only.) 180Specify that the address configured is an anycast address. 181Based on the current specification, 182only routers may configure anycast addresses. 183Anycast address will not be used as source address of any of outgoing 184IPv6 packets. 185.It Cm arp 186Enable the use of the Address Resolution Protocol 187.Pq Xr arp 4 188in mapping 189between network level addresses and link level addresses (default). 190This is currently implemented for mapping between 191.Tn DARPA 192Internet 193addresses and 194.Tn IEEE 195802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses). 196.It Fl arp 197Disable the use of the Address Resolution Protocol 198.Pq Xr arp 4 . 199.It Cm broadcast 200(Inet only.) 201Specify the address to use to represent broadcasts to the 202network. 203The default broadcast address is the address with a host part of all 1's. 204.It Cm debug 205Enable driver dependent debugging code; usually, this turns on 206extra console error logging. 207.It Fl debug 208Disable driver dependent debugging code. 209.It Cm delete 210Another name for the 211.Fl alias 212parameter. 213.It Cm down 214Mark an interface 215.Dq down . 216When an interface is marked 217.Dq down , 218the system will not attempt to 219transmit messages through that interface. 220If possible, the interface will be reset to disable reception as well. 221This action does not automatically disable routes using the interface. 222.It Cm ether 223Another name for the 224.Cm lladdr 225parameter. 226.\" .It Cm ipdst 227.\" This is used to specify an Internet host who is willing to receive 228.\" ip packets encapsulating NS packets bound for a remote network. 229.\" An apparent point to point link is constructed, and 230.\" the address specified will be taken as the NS address and network 231.\" of the destination. 232.\" IP encapsulation of 233.\" .Tn CLNP 234.\" packets is done differently. 235.It Cm lladdr Ar addr 236Set the link-level address on an interface. 237This can be used to 238e.g. set a new MAC address on an ethernet interface, though the 239mechanism used is not ethernet-specific. 240The address 241.Ar addr 242is specified as a series of colon-separated hex digits. 243If the interface is already 244up when this option is used, it will be briefly brought down and 245then brought back up again in order to ensure that the receive 246filter in the underlying ethernet hardware is properly reprogrammed. 247.It Cm media Ar type 248If the driver supports the media selection system, set the media type 249of the interface to 250.Ar type . 251Some interfaces support the mutually exclusive use of one of several 252different physical media connectors. 253For example, a 10Mb/s Ethernet 254interface might support the use of either 255.Tn AUI 256or twisted pair connectors. 257Setting the media type to 258.Dq 10base5/AUI 259would change the currently active connector to the AUI port. 260Setting it to 261.Dq 10baseT/UTP 262would activate twisted pair. 263Refer to the interfaces' driver 264specific documentation or man page for a complete list of the 265available types. 266.It Cm mediaopt Ar opts 267If the driver supports the media selection system, set the specified 268media options on the interface. 269The 270.Ar opts 271argument 272is a comma delimited list of options to apply to the interface. 273Refer to the interfaces' driver specific man page for a complete 274list of available options. 275.It Fl mediaopt Ar opts 276If the driver supports the media selection system, disable the 277specified media options on the interface. 278.It Cm tunnel Ar src_addr dest_addr 279(IP tunnel devices only.) 280Configure the physical source and destination address for IP tunnel 281interfaces 282.Pq Xr gif 4 . 283The arguments 284.Ar src_addr 285and 286.Ar dest_addr 287are interpreted as the outer source/destination for the encapsulating 288IPv4/IPv6 header. 289.It Cm deletetunnel 290Unconfigure the physical source and destination address for IP tunnel 291interfaces previously configured with 292.Cm tunnel . 293.It Cm create 294Create the specified network pseudo-device. 295If the interface is given without a unit number, try to create a new 296device with an arbitrary unit number. 297If creation of an arbitrary device is sucessful, the new device name is 298printed to standard output. 299.It Cm destroy 300Destroy the specified network pseudo-device. 301.It Cm plumb 302Another name for the 303.Cm create 304parameter. 305Included for 306.Tn Solaris 307compatibility. 308.It Cm unplumb 309Another name for the 310.Cm destroy 311parameter. 312Included for 313.Tn Solaris 314compatibility. 315.It Cm vlan Ar vlan_tag 316If the interface is a vlan pseudo interface, set the vlan tag value 317to 318.Ar vlan_tag . 319This value is a 16-bit number which is used to create an 802.1Q 320vlan header for packets sent from the vlan interface. 321Note that 322.Cm vlan 323and 324.Cm vlandev 325must both be set at the same time. 326.It Cm vlandev Ar iface 327If the interface is a vlan pseudo device, associate physical interface 328.Ar iface 329with it. 330Packets transmitted through the vlan interface will be 331diverted to the specified physical interface 332.Ar iface 333with 802.1Q vlan encapsulation. 334Packets with 802.1Q encapsulation received 335by the parent interface with the correct vlan tag will be diverted to 336the associated vlan pseudo-interface. 337The vlan interface is assigned a 338copy of the parent interface's flags and the parent's ethernet address. 339The 340.Cm vlandev 341and 342.Cm vlan 343must both be set at the same time. 344If the vlan interface already has 345a physical interface associated with it, this command will fail. 346To 347change the association to another physical interface, the existing 348association must be cleared first. 349.Pp 350Note: if the 351.Cm link0 352flag is set on the vlan interface, the vlan pseudo 353interface's behavior changes: the 354.Cm link0 355tells the vlan interface that the 356parent interface supports insertion and extraction of vlan tags on its 357own (usually in firmware) and that it should pass packets to and from 358the parent unaltered. 359.It Fl vlandev Ar iface 360If the driver is a vlan pseudo device, disassociate the physical interface 361.Ar iface 362from it. 363This breaks the link between the vlan interface and its parent, 364clears its vlan tag, flags and its link address and shuts the interface down. 365.It Cm metric Ar n 366Set the routing metric of the interface to 367.Ar n , 368default 0. 369The routing metric is used by the routing protocol 370.Pq Xr routed 8 . 371Higher metrics have the effect of making a route 372less favorable; metrics are counted as addition hops 373to the destination network or host. 374.It Cm mtu Ar n 375Set the maximum transmission unit of the interface to 376.Ar n , 377default is interface specific. 378The MTU is used to limit the size of packets that are transmitted on an 379interface. 380Not all interfaces support setting the MTU, and some interfaces have 381range restrictions. 382.It Cm netmask Ar mask 383.\" (Inet and ISO.) 384(Inet only.) 385Specify how much of the address to reserve for subdividing 386networks into sub-networks. 387The mask includes the network part of the local address 388and the subnet part, which is taken from the host field of the address. 389The mask can be specified as a single hexadecimal number 390with a leading 391.Ql 0x , 392with a dot-notation Internet address, 393or with a pseudo-network name listed in the network table 394.Xr networks 5 . 395The mask contains 1's for the bit positions in the 32-bit address 396which are to be used for the network and subnet parts, 397and 0's for the host part. 398The mask should contain at least the standard network portion, 399and the subnet field should be contiguous with the network 400portion. 401.Pp 402The netmask can also be specified in CIDR notation after the address. 403See the 404.Ar address 405option above for more information. 406.It Cm prefixlen Ar len 407(Inet6 only.) 408Specify that 409.Ar len 410bits are reserved for subdividing networks into sub-networks. 411The 412.Ar len 413must be integer, and for syntactical reason it must be between 0 to 128. 414It is almost always 64 under the current IPv6 assignment rule. 415If the parameter is omitted, 64 is used. 416.\" see 417.\" Xr eon 5 . 418.\" .It Cm nsellength Ar n 419.\" .Pf ( Tn ISO 420.\" only) 421.\" This specifies a trailing number of bytes for a received 422.\" .Tn NSAP 423.\" used for local identification, the remaining leading part of which is 424.\" taken to be the 425.\" .Tn NET 426.\" (Network Entity Title). 427.\" The default value is 1, which is conformant to US 428.\" .Tn GOSIP . 429.\" When an ISO address is set in an ifconfig command, 430.\" it is really the 431.\" .Tn NSAP 432.\" which is being specified. 433.\" For example, in 434.\" .Tn US GOSIP , 435.\" 20 hex digits should be 436.\" specified in the 437.\" .Tn ISO NSAP 438.\" to be assigned to the interface. 439.\" There is some evidence that a number different from 1 may be useful 440.\" for 441.\" .Tn AFI 442.\" 37 type addresses. 443.It Cm range Ar netrange 444Under appletalk, set the interface to respond to a 445.Ar netrange 446of the form 447.Ar startnet Ns - Ns Ar endnet . 448Appletalk uses this scheme instead of 449netmasks though 450.Fx 451implements it internally as a set of netmasks. 452.It Cm remove 453Another name for the 454.Fl alias 455parameter. 456Introduced for compatibility 457with 458.Bsx . 459.It Cm phase 460The argument following this specifies the version (phase) of the 461Appletalk network attached to the interface. 462Values of 1 or 2 are permitted. 463.Sm off 464.It Cm link Op Cm 0 No - Cm 2 465.Sm on 466Enable special processing of the link level of the interface. 467These three options are interface specific in actual effect, however, 468they are in general used to select special modes of operation. 469An example 470of this is to enable SLIP compression, or to select the connector type 471for some Ethernet cards. 472Refer to the man page for the specific driver 473for more information. 474.Sm off 475.It Fl link Op Cm 0 No - Cm 2 476.Sm on 477Disable special processing at the link level with the specified interface. 478.It Cm up 479Mark an interface 480.Dq up . 481This may be used to enable an interface after an 482.Dq Nm Cm down . 483It happens automatically when setting the first address on an interface. 484If the interface was reset when previously marked down, 485the hardware will be re-initialized. 486.It Cm ssid Ar ssid 487For IEEE 802.11 wireless interfaces, set the desired Service Set 488Identifier (aka network name). 489The SSID is a string up to 32 characters 490in length and may be specified as either a normal string or in 491hexadecimal when proceeded by 492.Ql 0x . 493Additionally, the SSID may be cleared by setting it to 494.Ql - . 495.It Cm nwid Ar ssid 496Another name for the 497.Cm ssid 498parameter. 499Included for 500.Nx 501compatibility. 502.It Cm stationname Ar name 503For IEEE 802.11 wireless interfaces, set the name of this station. 504It appears that the station name is not really part of the IEEE 802.11 505protocol though all interfaces seem to support it. 506As such it only 507seems to be meaningful to identical or virtually identical equipment. 508Setting the station name is identical in syntax to setting the SSID. 509.It Cm station Ar name 510Another name for the 511.Cm stationname 512parameter. 513Included for 514.Bsx 515compatibility. 516.It Cm channel Ar number 517For IEEE 802.11 wireless interfaces, set the desired channel. 518Channels range from 1 to 14, but the exact selection available 519depends on the region your adaptor was manufactured for. 520Setting 521the channel to 0 will give you the default for your adaptor. 522Many 523adaptors ignore this setting unless you are in ad-hoc mode. 524.It Cm authmode Ar mode 525For IEEE 802.11 wireless interfaces, set the desired authentication mode 526in infrastructure mode. 527Not all adaptors support all modes. 528The set of 529valid modes is 530.Dq none , 531.Dq open , 532and 533.Dq shared . 534Modes are case insensitive. 535.It Cm powersave 536For IEEE 802.11 wireless interfaces, enable powersave mode. 537.It Fl powersave 538For IEEE 802.11 wireless interfaces, disable powersave mode. 539.It Cm powersavesleep Ar sleep 540For IEEE 802.11 wireless interfaces, set the desired max powersave sleep 541time in milliseconds. 542.It Cm wepmode Ar mode 543For IEEE 802.11 wireless interfaces, set the desired WEP mode. 544Not all adaptors support all modes. 545The set of valid modes is 546.Dq off , 547.Dq on , 548and 549.Dq mixed . 550.Dq Mixed 551mode explicitly tells the adaptor to allow association with access 552points which allow both encrypted and unencrypted traffic. 553On these adaptors, 554.Dq on 555means that the access point must only allow encrypted connections. 556On other adaptors, 557.Dq on 558is generally another name for 559.Dq mixed . 560Modes are case insensitive. 561.It Cm weptxkey Ar index 562For IEEE 802.11 wireless interfaces, set the WEP key to be used for 563transmission. 564.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key 565For IEEE 802.11 wireless interfaces, set the selected WEP key. 566If an 567.Ar index 568is not given, key 1 is set. 569A WEP key will be either 5 or 13 570characters (40 or 104 bits) depending of the local network and the 571capabilities of the adaptor. 572It may be specified either as a plain 573string or as a string of hexadecimal digits proceeded by 574.Ql 0x . 575A key may be cleared by setting it to 576.Ql - . 577If WEP is supported then there are at least four keys. 578Some adaptors support more than four keys. 579If that is the case, then the first four keys 580(1-4) will be the standard temporary keys and any others will be adaptor 581specific keys such as permanent keys stored in NVRAM. 582.It Cm wep 583Another way of saying 584.Cm wepmode on . 585Included for 586.Bsx 587compatibility. 588.It Fl wep 589Another way of saying 590.Cm wepmode off . 591Included for 592.Bsx 593compatibility. 594.It Cm nwkey key 595Another way of saying: 596.Pp 597.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" . 598.Pp 599Included for 600.Nx 601compatibility. 602.It Cm nwkey Xo 603.Sm off 604.Ar n : k1 , k2 , k3 , k4 605.Sm on 606.Xc 607Another way of saying 608.Pp 609.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" . 610.Pp 611Included for 612.Nx 613compatibility. 614.It Fl nwkey 615Another way of saying 616.Cm wepmode off . 617.Pp 618Included for 619.Nx 620compatibility. 621.El 622.Pp 623.Nm Ifconfig 624displays the current configuration for a network interface 625when no optional parameters are supplied. 626If a protocol family is specified, 627.Nm 628will report only the details specific to that protocol family. 629.Pp 630If the driver does supports the media selection system, the supported 631media list will be included in the output. 632.Pp 633If the 634.Fl m 635flag is passed before an interface name, 636.Nm 637will display all 638of the supported media for the specified interface. 639If 640.Fl L 641flag is supplied, address lifetime is displayed for IPv6 addresses, 642as time offset string. 643.Pp 644Optionally, the 645.Fl a 646flag may be used instead of an interface name. 647This flag instructs 648.Nm 649to display information about all interfaces in the system. 650The 651.Fl d 652flag limits this to interfaces that are down, and 653.Fl u 654limits this to interfaces that are up. 655When no arguments are given, 656.Fl a 657is implied. 658.Pp 659The 660.Fl l 661flag may be used to list all available interfaces on the system, with 662no other additional information. 663Use of this flag is mutually exclusive 664with all other flags and commands, except for 665.Fl d 666(only list interfaces that are down) 667and 668.Fl u 669(only list interfaces that are up). 670.Pp 671The 672.Fl C 673flag may be used to list all of the interface cloners available on 674the system, with no additional information. 675Use of this flag is mutually exclusive with all other flags and commands. 676.Pp 677Only the super-user may modify the configuration of a network interface. 678.Sh NOTES 679The media selection system is relatively new and only some drivers support 680it (or have need for it). 681.Sh DIAGNOSTICS 682Messages indicating the specified interface does not exist, the 683requested address is unknown, or the user is not privileged and 684tried to alter an interface's configuration. 685.Sh BUGS 686IPv6 link-local addresses are required for several basic communication 687between IPv6 node. 688If they are deleted by 689.Nm 690manually, the kernel might show very strange behavior. 691So, such manual deletions are strongly discouraged. 692.Sh SEE ALSO 693.Xr netstat 1 , 694.Xr netintro 4 , 695.\" .Xr eon 5 , 696.Xr rc 8 , 697.Xr routed 8 698.Sh HISTORY 699The 700.Nm 701command appeared in 702.Bx 4.2 . 703