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.\" $Id: route.8,v 1.11 1997/06/18 06:30:34 charnier Exp $ 34.\" 35.Dd March 19, 1994 36.Dt ROUTE 8 37.Os BSD 4.4 38.Sh NAME 39.Nm route 40.Nd manually manipulate the routing tables 41.Sh SYNOPSIS 42.Nm route 43.Op Fl dnqtv 44.Ar command 45.Oo 46.Op Ar modifiers 47.Ar args 48.Oc 49.Sh DESCRIPTION 50.Nm Route 51is a utility used to manually manipulate the network 52routing tables. It normally is not needed, as a 53system routing table management daemon such as 54.Xr routed 8 , 55should tend to this task. 56.Pp 57The 58.Nm 59utility supports a limited number of general options, 60but a rich command language, enabling the user to specify 61any arbitrary request that could be delivered via the 62programmatic interface discussed in 63.Xr route 4 . 64.Pp 65The following options are available: 66.Bl -tag -width indent 67.It Fl n 68Bypass attempts to print host and network names symbolically 69when reporting actions. (The process of translating between symbolic 70names and numerical equivalents can be quite time consuming, and 71may require correct operation of the network; thus it may be expedient 72to forgot this, especially when attempting to repair networking operations). 73.It Fl v 74(verbose) Print additional details. 75.It Fl q 76Suppress all output. 77.El 78.Pp 79The 80.Nm 81utility provides six commands: 82.Pp 83.Bl -tag -width Fl -compact 84.It Cm add 85Add a route. 86.It Cm flush 87Remove all routes. 88.It Cm delete 89Delete a specific route. 90.It Cm change 91Change aspects of a route (such as its gateway). 92.It Cm get 93Lookup and display the route for a destination. 94.It Cm monitor 95Continuously report any changes to the routing information base, 96routing lookup misses, or suspected network partitionings. 97.El 98.Pp 99The monitor command has the syntax: 100.Pp 101.Bd -filled -offset indent -compact 102.Nm route Op Fl n 103.Cm monitor 104.Ed 105.Pp 106The flush command has the syntax: 107.Pp 108.Bd -filled -offset indent -compact 109.Nm route Op Fl n 110.Cm flush 111.Op Ar family 112.Ed 113.Pp 114If the 115.Cm flush 116command is specified, 117.Nm 118will ``flush'' the routing tables of all gateway entries. 119When the address family may is specified by any of the 120.Fl osi , 121.Fl xns , 122.Fl atalk , 123or 124.Fl inet 125modifiers, only routes having destinations with addresses in the 126delineated family will be deleted. 127.Pp 128The other commands have the following syntax: 129.Pp 130.Bd -filled -offset indent -compact 131.Nm route Op Fl n 132.Ar command 133.Op Fl net No \&| Fl host 134.Ar destination gateway 135.Ed 136.Pp 137where 138.Ar destination 139is the destination host or network, 140.Ar gateway 141is the next-hop intermediary via which packets should be routed. 142Routes to a particular host may be distinguished from those to 143a network by interpreting the Internet address specified as the 144.Ar destination argument . 145The optional modifiers 146.Fl net 147and 148.Fl host 149force the destination to be interpreted as a network or a host, respectively. 150Otherwise, if the 151.Ar destination 152has a ``local address part'' of 153INADDR_ANY , 154or if the 155.Ar destination 156is the symbolic name of a network, then the route is 157assumed to be to a network; otherwise, it is presumed to be a 158route to a host. 159.Pp 160For example, 161.Li 128.32 162is interpreted as 163.Fl host Li 128.0.0.32 ; 164.Li 128.32.130 165is interpreted as 166.Fl host Li 128.32.0.130 ; 167.Fl net Li 128.32 168is interpreted as 169.Li 128.32.0.0; 170and 171.Fl net Li 128.32.130 172is interpreted as 173.Li 128.32.130.0 . 174.Pp 175If the destination is directly reachable 176via an interface requiring 177no intermediary system to act as a gateway, the 178.Fl interface 179modifier should be specified; 180the gateway given is the address of this host on the common network, 181indicating the interface to be used for transmission. 182Alternately, if the interface is point to point the name of the interface 183itself may be given, in which case the route remains valid even 184if the local or remote addresses change. 185.Pp 186The optional modifiers 187.Fl xns , 188.Fl osi , 189.Fl atalk , 190and 191.Fl link 192specify that all subsequent addresses are in the 193.Tn XNS , 194.Tn OSI , 195or 196.Tn AppleTalk 197address families, 198or are specified as link-level addresses, 199and the names must be numeric specifications rather than 200symbolic names. 201.Pp 202The optional 203.Fl netmask 204modifier is intended 205to achieve the effect of an 206.Tn OSI 207.Tn ESIS 208redirect with the netmask option, 209or to manually add subnet routes with 210netmasks different from that of the implied network interface 211(as would otherwise be communicated using the OSPF or ISIS routing protocols). 212One specifies an additional ensuing address parameter 213(to be interpreted as a network mask). 214The implicit network mask generated in the AF_INET case 215can be overridden by making sure this option follows the destination parameter. 216.Pp 217Routes have associated flags which influence operation of the protocols 218when sending to destinations matched by the routes. 219These flags may be set (or sometimes cleared) 220by indicating the following corresponding modifiers: 221.Bd -literal 222-cloning RTF_CLONING - generates a new route on use 223-xresolve RTF_XRESOLVE - emit mesg on use (for external lookup) 224-iface ~RTF_GATEWAY - destination is directly reachable 225-static RTF_STATIC - manually added route 226-nostatic ~RTF_STATIC - pretend route added by kernel or daemon 227-reject RTF_REJECT - emit an ICMP unreachable when matched 228-blackhole RTF_BLACKHOLE - silently discard pkts (during updates) 229-proto1 RTF_PROTO1 - set protocol specific routing flag #1 230-proto2 RTF_PROTO2 - set protocol specific routing flag #2 231-llinfo RTF_LLINFO - validly translates proto addr to link addr 232.Ed 233.Pp 234The optional modifiers 235.Fl rtt , 236.Fl rttvar , 237.Fl sendpipe , 238.Fl recvpipe , 239.Fl mtu , 240.Fl hopcount , 241.Fl expire , 242and 243.Fl ssthresh 244provide initial values to quantities maintained in the routing entry 245by transport level protocols, such as TCP or TP4. 246These may be individually locked by preceding each such modifier to 247be locked by 248the 249.Fl lock 250meta-modifier, or one can 251specify that all ensuing metrics may be locked by the 252.Fl lockrest 253meta-modifier. 254.Pp 255In a 256.Cm change 257or 258.Cm add 259command where the destination and gateway are not sufficient to specify 260the route (as in the 261.Tn ISO 262case where several interfaces may have the 263same address), the 264.Fl ifp 265or 266.Fl ifa 267modifiers may be used to determine the interface or interface address. 268.Pp 269All symbolic names specified for a 270.Ar destination 271or 272.Ar gateway 273are looked up first as a host name using 274.Xr gethostbyname 3 . 275If this lookup fails, 276.Xr getnetbyname 3 277is then used to interpret the name as that of a network. 278.Pp 279.Nm Route 280uses a routing socket and the new message types 281RTM_ADD, 282RTM_DELETE, 283RTM_GET, 284and 285RTM_CHANGE. 286As such, only the super-user may modify 287the routing tables. 288.Sh DIAGNOSTICS 289.Bl -tag -width Ds 290.It Sy "add [host \&| network ] %s: gateway %s flags %x" 291The specified route is being added to the tables. The 292values printed are from the routing table entry supplied 293in the 294.Xr ioctl 2 295call. 296If the gateway address used was not the primary address of the gateway 297(the first one returned by 298.Xr gethostbyname 3 ) , 299the gateway address is printed numerically as well as symbolically. 300.It Sy "delete [ host &| network ] %s: gateway %s flags %x" 301As above, but when deleting an entry. 302.It Sy "%s %s done" 303When the 304.Cm flush 305command is specified, each routing table entry deleted 306is indicated with a message of this form. 307.It Sy "Network is unreachable" 308An attempt to add a route failed because the gateway listed was not 309on a directly-connected network. 310The next-hop gateway must be given. 311.It Sy "not in table" 312A delete operation was attempted for an entry which 313wasn't present in the tables. 314.It Sy "routing table overflow" 315An add operation was attempted, but the system was 316low on resources and was unable to allocate memory 317to create the new entry. 318.El 319.Sh SEE ALSO 320.Xr netintro 4 , 321.Xr route 4 , 322.Xr IPXrouted 8 , 323.Xr routed 8 324.\" .Xr XNSrouted 8 325.\" Xr esis 4 , 326.Sh HISTORY 327The 328.Nm 329command appeared in 330.Bx 4.2 . 331.Sh BUGS 332The first paragraph may have slightly exaggerated 333.Xr routed 8 Ns 's 334abilities. 335