1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)route.8 8.3 (Berkeley) 03/19/94 7.\" 8.Dd 9.Dt ROUTE 8 10.Os BSD 4.4 11.Sh NAME 12.Nm route 13.Nd manually manipulate the routing tables. 14.Sh SYNOPSIS 15.Nm route 16.Op Fl nqv 17.Ar command 18.Oo 19.Op Ar modifiers 20.Ar args 21.Oc 22.Sh DESCRIPTION 23.Nm Route 24is a utility used to manually manipulate the network 25routing tables. It normally is not needed, as a 26system routing table management daemon such as 27.Xr routed 8 , 28should tend to this task. 29.Pp 30The 31.Nm route : 32utility supports a limited number of general options, 33but a rich command language, enabling the user to specify 34any arbitrary request that could be delivered via the 35programmatic interface discussed in 36.Xr route 4 . 37.Pp 38.Bl -tag -width Ds 39.It Fl n 40Bypasses attempts to print host and network names symbolically 41when reporting actions. (The process of translating between symbolic 42names and numerical equivalents can be quite time consuming, and 43may require correct operation of the network; thus it may be expedient 44to forgo this, especially when attempting to repair networking operations), 45.It Fl v 46(verbose) Print additional details. 47.It Fl q 48Suppress all output. 49.El 50.Pp 51The 52.Nm route : 53utility provides six commands: 54.Pp 55.Bl -tag -width Fl -compact 56.It Cm add 57Add a route. 58.It Cm flush 59Remove all routes. 60.It Cm delete 61Delete a specific route. 62.It Cm change 63Change aspects of a route (such as its gateway). 64.It Cm get 65Lookup and display the route for a destination. 66.It Cm monitor 67Continuously report any changes to the routing information base, 68routing lookup misses, or suspected network partitionings. 69.El 70.Pp 71The monitor command has the syntax 72.Pp 73.Bd -filled -offset indent -compact 74.Nm route Op Fl n 75.Cm monitor 76.Ed 77.Pp 78The flush command has the syntax 79.Pp 80.Bd -filled -offset indent -compact 81.Nm route Op Fl n 82.Cm flush 83.Op Ar family 84.Ed 85.Pp 86If the 87.Cm flush 88command is specified, 89.Nm route 90will ``flush'' the routing tables of all gateway entries. 91When the address family may is specified by any of the 92.Fl osi , 93.Fl xns , 94or 95.Fl inet 96modifiers, only routes having destinations with addresses in the 97delineated family will be deleted. 98.Pp 99The other commands have the following syntax: 100.Pp 101.Bd -filled -offset indent -compact 102.Nm route Op Fl n 103.Ar command 104.Op Fl net No \&| Fl host 105.Ar destination gateway 106.Ed 107.Pp 108where 109.Ar destination 110is the destination host or network, 111.Ar gateway 112is the next-hop intermediary via which packets should be routed. 113Routes to a particular host may be distinguished from those to 114a network by interpreting the Internet address specified as the 115.Ar destination argument. 116The optional modifiers 117.Fl net 118and 119.Fl host 120force the destination to be interpreted as a network or a host, respectively. 121Otherwise, if the 122.Ar destination 123has a ``local address part'' of 124INADDR_ANY , 125or if the 126.Ar destination 127is the symbolic name of a network, then the route is 128assumed to be to a network; otherwise, it is presumed to be a 129route to a host. 130.Pp 131For example, 132.Li 128.32 133is interpreted as 134.Fl host Li 128.0.0.32 ; 135.Li 128.32.130 136is interpreted as 137.Fl host Li 128.32.0.130 ; 138.Fl net Li 128.32 139is interpreted as 140.Li 128.32.0.0; 141and 142.Fl net Li 128.32.130 143is interpreted as 144.Li 128.32.130.0 . 145.Pp 146If the destination is directly reachable 147via an interface requiring 148no intermediary system to act as a gateway, the 149.Fl interface 150modifier should be specified; 151the gateway given is the address of this host on the common network, 152indicating the interface to be used for transmission. 153.Pp 154The optional modifiers 155.Fl xns , 156.Fl osi , 157and 158.Fl link 159specify that all subsequent addresses are in the 160.Tn XNS 161.Tn OSI 162address families, 163or are specified as link-level addresses, 164and the names must be numeric specifications rather than 165symbolic names. 166.Pp 167The optional 168.Fl netmask 169qualifier is intended 170to achieve the effect of an 171.Tn OSI 172.Tn ESIS 173redirect with the netmask option, 174or to manually add subnet routes with 175netmasks different from that of the implied network interface 176(as would otherwise be communicated using the OSPF or ISIS routing protocols). 177One specifies an additional ensuing address parameter 178(to be interpreted as a network mask). 179The implicit network mask generated in the AF_INET case 180can be overridden by making sure this option follows the destination parameter. 181.Pp 182Routes have associated flags which influence operation of the protocols 183when sending to destinations matched by the routes. 184These flags may be set (or sometimes cleared) 185by indicating the following corresponding modifiers: 186.Bd -literal 187-cloning RTF_CLONING - generates a new route on use 188-xresolve RTF_XRESOLVE - emit mesg on use (for external lookup) 189-iface ~RTF_GATEWAY - destination is directly reachable 190-static RTF_STATIC - manually added route 191-nostatic ~RTF_STATIC - pretend route added by kernel or daemon 192-reject RTF_REJECT - emit an ICMP unreachable when matched 193-blackhole RTF_BLACKHOLE - silently discard pkts (during updates) 194-proto1 RTF_PROTO1 - set protocol specific routing flag #1 195-proto2 RTF_PROTO2 - set protocol specific routing flag #2 196-llinfo RTF_LLINFO - validly translates proto addr to link addr 197.Ed 198.Pp 199The optional modifiers 200.Fl rtt , 201.Fl rttvar , 202.Fl sendpipe , 203.Fl recvpipe , 204.Fl mtu , 205.Fl hopcount , 206.Fl expire , 207and 208.Fl ssthresh 209provide initial values to quantities maintained in the routing entry 210by transport level protocols, such as TCP or TP4. 211These may be individually locked by preceding each such modifier to 212be locked by 213the 214.Fl lock 215meta-modifier, or one can 216specify that all ensuing metrics may be locked by the 217.Fl lockrest 218meta-modifier. 219.Pp 220In a 221.Cm change 222or 223.Cm add 224command where the destination and gateway are not sufficient to specify 225the route (as in the 226.Tn ISO 227case where several interfaces may have the 228same address), the 229.Fl ifp 230or 231.Fl ifa 232modifiers may be used to determine the interface or interface address. 233.Pp 234All symbolic names specified for a 235.Ar destination 236or 237.Ar gateway 238are looked up first as a host name using 239.Xr gethostbyname 3 . 240If this lookup fails, 241.Xr getnetbyname 3 242is then used to interpret the name as that of a network. 243.Pp 244.Nm Route 245uses a routing socket and the new message types 246RTM_ADD, 247RTM_DELETE, 248RTM_GET, 249and 250RTM_CHANGE. 251As such, only the super-user may modify 252the routing tables. 253.Sh DIAGNOSTICS 254.Bl -tag -width Ds 255.It Sy "add [host \&| network ] %s: gateway %s flags %x" 256The specified route is being added to the tables. The 257values printed are from the routing table entry supplied 258in the 259.Xr ioctl 2 260call. 261If the gateway address used was not the primary address of the gateway 262(the first one returned by 263.Xr gethostbyname 3 ) , 264the gateway address is printed numerically as well as symbolically. 265.It Sy "delete [ host &| network ] %s: gateway %s flags %x" 266As above, but when deleting an entry. 267.It Sy "%s %s done" 268When the 269.Cm flush 270command is specified, each routing table entry deleted 271is indicated with a message of this form. 272.It Sy "Network is unreachable" 273An attempt to add a route failed because the gateway listed was not 274on a directly-connected network. 275The next-hop gateway must be given. 276.It Sy "not in table" 277A delete operation was attempted for an entry which 278wasn't present in the tables. 279.It Sy "routing table overflow" 280An add operation was attempted, but the system was 281low on resources and was unable to allocate memory 282to create the new entry. 283.El 284.Sh SEE ALSO 285.Xr netintro 4 , 286.Xr route 4 , 287.Xr esis 4 , 288.Xr routed 8 , 289.Xr XNSrouted 8 290.Sh HISTORY 291The 292.Nm 293command appeared in 294.Bx 4.2 . 295.Sh BUGS 296The first paragraph may have slightly exaggerated 297.Xr routed Ns 's 298abilities. 299