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 acknowledgement: 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.\" @(#)route.8 8.3 (Berkeley) 3/19/94 33.\" $FreeBSD: src/sbin/route/route.8,v 1.17.2.9 2003/02/24 00:56:43 trhodes Exp $ 34.\" 35.Dd June 8, 2001 36.Dt ROUTE 8 37.Os 38.Sh NAME 39.Nm route 40.Nd manually manipulate the routing tables 41.Sh SYNOPSIS 42.Nm 43.Op Fl dnqtv 44.Op Fl c Ar cpu 45.Ar command 46.Oo 47.Op Ar modifiers 48.Ar args 49.Oc 50.Sh DESCRIPTION 51The 52.Nm 53utility is used to manually manipulate the network 54routing tables. It normally is not needed, as a 55system routing table management daemon such as 56.Xr routed 8 , 57should tend to this task. 58.Pp 59The 60.Nm 61utility supports a limited number of general options, 62but a rich command language, enabling the user to specify 63any arbitrary request that could be delivered via the 64programmatic interface discussed in 65.Xr route 4 . 66.Pp 67The following options are available: 68.Bl -tag -width indent 69.It Fl c Ar cpu 70On SMP systems the route table is replicated. This option allows the 71route table for a specific cpu to be accessed and exists primarily 72for debugging purposes. 73.It Fl n 74Bypass attempts to print host and network names symbolically 75when reporting actions. (The process of translating between symbolic 76names and numerical equivalents can be quite time consuming, and 77may require correct operation of the network; thus it may be expedient 78to forget this, especially when attempting to repair networking operations). 79.It Fl v 80(verbose) Print additional details. 81.It Fl q 82Suppress all output from the 83.Cm add , delete , 84and 85.Cm flush 86commands. 87.It Fl w 88Print the full width of the data being represented even if it would overflow 89the column. 90.El 91.Pp 92The 93.Nm 94utility provides six commands: 95.Pp 96.Bl -tag -width Fl -compact 97.It Cm add 98Add a route. 99.It Cm flush 100Remove all routes. 101.It Cm delete 102Delete a specific route. 103.It Cm change 104Change aspects of a route (such as its gateway). 105.It Cm get 106Lookup and display the route for a destination. 107.It Cm show 108Print out the route table similar to "netstat \-r" (see 109.Xr netstat 1 ) . 110.It Cm monitor 111Continuously report any changes to the routing information base, 112routing lookup misses, or suspected network partitionings. 113.El 114.Pp 115The monitor command has the syntax: 116.Pp 117.Bd -ragged -offset indent -compact 118.Nm 119.Op Fl n 120.Cm monitor 121.Ed 122.Pp 123The flush command has the syntax: 124.Pp 125.Bd -ragged -offset indent -compact 126.Nm 127.Op Fl n 128.Cm flush 129.Op Ar family 130.Ed 131.Pp 132If the 133.Cm flush 134command is specified, 135.Nm 136will ``flush'' the routing tables of all gateway entries. 137When the address family may is specified by any of the 138.Fl osi , 139.Fl xns , 140.Fl inet6 , 141or 142.Fl inet 143modifiers, only routes having destinations with addresses in the 144delineated family will be deleted. 145.Pp 146The other commands have the following syntax: 147.Pp 148.Bd -ragged -offset indent -compact 149.Nm 150.Op Fl n 151.Ar command 152.Op Fl net No \&| Fl host 153.Ar destination gateway 154.Op Ar netmask 155.Ed 156.Pp 157where 158.Ar destination 159is the destination host or network, 160.Ar gateway 161is the next-hop intermediary via which packets should be routed. 162Routes to a particular host may be distinguished from those to 163a network by interpreting the Internet address specified as the 164.Ar destination 165argument. 166The optional modifiers 167.Fl net 168and 169.Fl host 170force the destination to be interpreted as a network or a host, respectively. 171Otherwise, if the 172.Ar destination 173has a 174.Dq local address part 175of 176INADDR_ANY 177.Pq Li 0.0.0.0 , 178or if the 179.Ar destination 180is the symbolic name of a network, then the route is 181assumed to be to a network; otherwise, it is presumed to be a 182route to a host. 183Optionally, the 184.Ar destination 185could also be specified in the 186.Ar net Ns / Ns Ar bits 187format. 188.Pp 189For example, 190.Li 128.32 191is interpreted as 192.Fl host Li 128.0.0.32 ; 193.Li 128.32.130 194is interpreted as 195.Fl host Li 128.32.0.130 ; 196.Fl net Li 128.32 197is interpreted as 198.Li 128.32.0.0; 199.Fl net Li 128.32.130 200is interpreted as 201.Li 128.32.130.0; 202and 203.Li 192.168.64/20 204is interpreted as 205.Fl net Li 192.168.64 Fl netmask Li 255.255.240.0 . 206.Pp 207A 208.Ar destination 209of 210.Ar default 211is a synonym for 212.Fl net Li 0.0.0.0 , 213which is the default route. 214.Pp 215If the destination is directly reachable 216via an interface requiring 217no intermediary system to act as a gateway, the 218.Fl interface 219modifier should be specified; 220the gateway given is the address of this host on the common network, 221indicating the interface to be used for transmission. 222Alternately, if the interface is point to point the name of the interface 223itself may be given, in which case the route remains valid even 224if the local or remote addresses change. 225.Pp 226The optional modifiers 227.Fl mpls , 228.Fl xns , 229.Fl osi , 230and 231.Fl link 232specify that all subsequent addresses are in the 233.Tn MPLS , 234.Tn XNS , 235or 236.Tn OSI 237address families, 238or are specified as link-level addresses, 239and the names must be numeric specifications rather than 240symbolic names. 241.Pp 242The optional 243.Fl netmask 244modifier is intended 245to achieve the effect of an 246.Tn OSI 247.Tn ESIS 248redirect with the netmask option, 249or to manually add subnet routes with 250netmasks different from that of the implied network interface 251(as would otherwise be communicated using the OSPF or ISIS routing protocols). 252One specifies an additional ensuing address parameter 253(to be interpreted as a network mask). 254The implicit network mask generated in the AF_INET case 255can be overridden by making sure this option follows the destination parameter. 256.Pp 257For 258.Dv AF_INET6 , 259the 260.Fl prefixlen 261qualifier 262is available instead of the 263.Fl mask 264qualifier because non-continuous masks are not allowed in IPv6. 265For example, 266.Fl prefixlen Li 32 267specifies network mask of 268.Li ffff:ffff:0000:0000:0000:0000:0000:0000 269to be used. 270The default value of prefixlen is 64 to get along with 271the aggregatable address. 272But 0 is assumed if 273.Cm default 274is specified. 275Note that the qualifier works only for 276.Dv AF_INET6 277address family. 278.Pp 279Routes have associated flags which influence operation of the protocols 280when sending to destinations matched by the routes. 281These flags may be set (or sometimes cleared) 282by indicating the following corresponding modifiers: 283.Bd -literal 284-cloning RTF_CLONING - generates a new route on use 285-xresolve RTF_XRESOLVE - emit mesg on use (for external lookup) 286-iface ~RTF_GATEWAY - destination is directly reachable 287-static RTF_STATIC - manually added route 288-nostatic ~RTF_STATIC - pretend route added by kernel or daemon 289-reject RTF_REJECT - emit an ICMP unreachable when matched 290-blackhole RTF_BLACKHOLE - silently discard pkts (during updates) 291-proto1 RTF_PROTO1 - set protocol specific routing flag #1 292-proto2 RTF_PROTO2 - set protocol specific routing flag #2 293-llinfo RTF_LLINFO - validly translates proto addr to link addr 294.Ed 295.Pp 296The optional modifiers 297.Fl rtt , 298.Fl rttvar , 299.Fl sendpipe , 300.Fl recvpipe , 301.Fl mtu , 302.Fl hopcount , 303.Fl expire , 304and 305.Fl ssthresh 306provide initial values to quantities maintained in the routing entry 307by transport level protocols, such as TCP or TP4. 308These may be individually locked by preceding each such modifier to 309be locked by 310the 311.Fl lock 312meta-modifier, or one can 313specify that all ensuing metrics may be locked by the 314.Fl lockrest 315meta-modifier. 316.Pp 317In a 318.Cm change 319or 320.Cm add 321command where the destination and gateway are not sufficient to specify 322the route (as in the 323.Tn ISO 324case where several interfaces may have the 325same address), the 326.Fl ifp 327or 328.Fl ifa 329modifiers may be used to determine the interface or interface address. 330.Pp 331The optional 332.Fl proxy 333modifier specifies that the 334.Dv RTF_LLINFO 335routing table entry is the 336.Dq published (proxy-only) 337.Tn ARP 338entry, as reported by 339.Xr arp 8 . 340.Pp 341All symbolic names specified for a 342.Ar destination 343or 344.Ar gateway 345are looked up first as a host name using 346.Xr gethostbyname 3 . 347If this lookup fails, 348.Xr getnetbyname 3 349is then used to interpret the name as that of a network. 350.Pp 351The optional 352.Fl push , 353.Fl pop , 354and 355.Fl swap 356modifiers may be used to specify the desired mpls label 357operations for the route. Each route may have up to 3 358label operations assigned to it. The label operations 359may be combined between them, but specifically the 360.Fl push 361and 362.Fl pop 363operations may be repeated if the intent is to push or pop 364more than one label at once. The 365.Fl swap 366operation always swaps the outer label and may not be 367repeated. 368Here are some MPLS route examples: 369.Pp 370Add an normal inet route, but push an mpls 371.Ar label 372to the packet: 373.Pp 374.Bd -ragged -offset indent -compact 375.Nm 376.Cm add 377.Ar destination gateway 378.Fl push 379.Ar label 380.Ed 381.Pp 382Add an normal inet route, but double-push an mpls 383.Ar inner-label 384and an 385.Ar outer-label 386to the packet: 387.Pp 388.Bd -ragged -offset indent -compact 389.Nm 390.Cm add 391.Ar destination gateway 392.Fl push 393.Ar inner-label 394.Fl push 395.Ar outer-label 396.Ed 397.Pp 398Add an mpls route for an 399.Ar incoming-label 400to be forwarded to 401.Ar gateway 402and swap that label with 403.Ar new-label : 404.Pp 405.Bd -ragged -offset indent -compact 406.Nm 407.Cm add 408.Fl mpls 409.Ar incoming-label 410.Fl inet 411.Ar gateway 412.Fl swap 413.Ar new-label 414.Ed 415.Pp 416The 417.Nm 418utility uses a routing socket and the new message types 419.Dv RTM_ADD , RTM_DELETE , RTM_GET , 420and 421.Dv RTM_CHANGE . 422As such, only the super-user may modify 423the routing tables. 424.Sh EXIT STATUS 425.Ex -std 426.Sh DIAGNOSTICS 427.Bl -diag 428.It "add [host \&| network ] %s: gateway %s flags %x" 429The specified route is being added to the tables. The 430values printed are from the routing table entry supplied 431in the 432.Xr ioctl 2 433call. 434If the gateway address used was not the primary address of the gateway 435(the first one returned by 436.Xr gethostbyname 3 ) , 437the gateway address is printed numerically as well as symbolically. 438.It "delete [ host \&| network ] %s: gateway %s flags %x" 439As above, but when deleting an entry. 440.It "%s %s done" 441When the 442.Cm flush 443command is specified, each routing table entry deleted 444is indicated with a message of this form. 445.It "Network is unreachable" 446An attempt to add a route failed because the gateway listed was not 447on a directly-connected network. 448The next-hop gateway must be given. 449.It "not in table" 450A delete operation was attempted for an entry which 451wasn't present in the tables. 452.It "routing table overflow" 453An add operation was attempted, but the system was 454low on resources and was unable to allocate memory 455to create the new entry. 456.It "gateway uses the same route" 457A 458.Cm change 459operation resulted in a route whose gateway uses the 460same route as the one being changed. 461The next-hop gateway should be reachable through a different route. 462.El 463.Sh SEE ALSO 464.\".Xr esis 4 , 465.Xr netintro 4 , 466.Xr route 4 , 467.Xr arp 8 , 468.Xr IPXrouted 8 , 469.Xr routed 8 470.\".Xr XNSrouted 8 471.Sh HISTORY 472The 473.Nm 474utility appeared in 475.Bx 4.2 . 476.Sh BUGS 477The first paragraph may have slightly exaggerated 478.Xr routed 8 Ns 's 479abilities. 480