ROUTE(8C)                       Domain/OS BSD                        ROUTE(8C)




NAME
     route - manually manipulate the routing tables

SYNOPSIS
     /etc/route [-f] [-n] [command args]

DESCRIPTION
     route is a program used to manually manipulate the network routing
     tables.  It normally is not needed, as the system routing table
     management daemon, routed(8C), should tend to this task.

     route accepts three commands:  add, to add a route; addp, to add a
     priority route; and delete, to delete a route.

     The addp command adds a priority route.  The TCP/IP server process will
     use priority routes before default routes or routes established by
     routed(8C). A route added with addp will appear first in the gateway
     table (displayed with the BSD command netstat -r(1)). You can only add
     priority routes with addp.  Routes added manually by route cannot be
     deleted by routed(8C).

COMMAND SYNTAX
     All commands have the following syntax:

       /etc/route command [ net | host ] destination gateway [ metric ]

     where destination is the destination host or network, gateway is the
     next-hop gateway to which packets should be addressed, and metric is a
     count indicating the number of hops to the destination.  The metric is
     required for add and addp commands; it must be greater than zero if the
     destination is on a directly-attached network or if the route utilizes
     one or more gateways.  (See the Notes section below for important
     information about adding routes to gateways on directly-attached
     networks.)

     The route command does not support subnet addresses as part of symbolic
     or numeric destination network names.  A destination network address that
     includes a subnet portion will be misinterpreted, resulting in an
     incorrect address.

     Any symbolic name specified for destination or gateway is looked up first
     as a net name by getnetbyname(3N).  If this lookup fails,
     gethostbyname(3N) then interprets the name as a host name.

     For numeric names, routes to a particular host are distinguished from
     those to a network by interpreting the Internet address associated with
     destination.  The optional keywords net (default) and host force
     destination to be interpreted in network or host format, respectively.
     When the optional keyword net is not specified, a numeric destination
     address takes the complete Internet address format specified in inet(3N).
     A destination specified in this way can be either a host or network,
     depending on whether the "local address part" is INADDR_ANY.

     When the optional keyword net is specified, a numeric destination name is
     interpreted as giving only the network portion of the Internet address.
     Any subnet or host portion in the numeric destination network name will
     be misinterpreted and result in an incorrect address.  A "local address
     part" of INADDR_ANY is then appended to the given network address to form
     the complete Internet address of the destination network.

     For example, 128.32 or host 128.32 is interpreted as 128.0.0.32;
     128.32.130 or host 128.32.130 is interpreted as 128.32.0.130;
     net 128.32 is interpreted as 128.32.0.0;
     and net 128.32.130 is interpreted as 128.32.130.0.

     You can add a default route as follows:

        /etc/route add default gateway_name [non-zero metric]

     TCP/IP software will use the default route when other routes occuring
     earlier in the routing table have failed, or when there are no other
     possible routes.

     route uses a raw socket and the SIOCADDRT and SIOCDELRT ioctl's(2) to do
     its work.  As such, only the super-user may modify the routing tables.

OPTIONS
     -f     "Flush" the routing tables of all gateway entries.  Using this
            option in conjunction with one of the commands described above
            flushes the tables prior to the command's application.  Note that
            if you start routed prior to using the route -f command, routed is
            not aware that tcpd's routing tables have been flushed.
            Therefore, routed does not automatically tell tcpd about all of
            its routes.  For this reason, we recommend that you do not use the
            route -f command when you are also running routed, unless you
            restart routed after the route -f command successfully completes.
            When you restart routed, as part of its initialization, it tells
            tcpd about all of its known routes.

     -n     Suppress printing symbolic host and network names when reporting
            actions.

DIAGNOSTICS
     add [ host | network ] %s: gateway %s flags %x

          The specified route is being added to the tables.  The values
          printed are from the routing table entry supplied in the ioctl(2)
          call.  If the gateway address used was not the primary address of
          the gateway (the first one returned by gethostbyname(3N)), the
          gateway address is printed numerically as well as symbolically.

     delete [ host | network ] %s: gateway %s flags %x

          As above, but when deleting an entry.

     %s %s done

          When the -f flag is specified, each routing table entry deleted is
          indicated with a message of this form.

     Network is unreachable

          An attempt to add a route failed because the gateway listed was not
          on a directly-connected network.  The next-hop gateway must be
          given.

     not in table

          A delete operation was attempted for an entry that wasn't present in
          the tables.

     routing table overflow

          An add operation was attempted, but the system was low on resources
          and was unable to allocate memory to create the new entry.

NOTES
     If you attempt to use metric 0 to add a regular or priority route to a
     gateway on a directly-connected network, the metric is automatically
     incremented to 1 and the connection fails.  This occurs because we do not
     support configurations with multiple logical networks on a single
     physical network.  All nodes on the same physical network must have the
     same network address.  If your network is subnetted, all nodes must also
     have the same subnet number.

SEE ALSO
     intro(4N), routed(8C);
     Configuring and Managing TCP/IP.