destination The destination host or network (with or
without the optional Classless Inter-Domain
Routing (CIDR) mask (/bitmask)).
gateway The next hop and gateway to which packets
should be addressed. Routes to a particular
host are distinguished from those to a
network by interpreting the Internet address
associated with destination.
[-net | -host] Forces the destination to be interpreted
as a network addres or as a host address,
respectively. Otherwise, if the destination
has a local address part of INADDR_ANY, or
if the destination is the symbolic name of a
network, then the route is assumed to be to
a network; otherwise, it is presumed to be a
route to a host.
For example, 128.32 is interpreted as -host
128.0.0.32, 128.32.130 is interpreted as -host
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.
[family] Specifies the optional address family of the
destination and gateway parameters. Possible
values are: -inet (the default) and -inet6.
If the -link parameter is not specified,
this also specifies the address family of
the gateway parameter.
[-link] Specifies that the gateway is a link layer
address. If the -link parameter is not
specified, the address family of the gateway
parameter is the same as the destination.
The optional modifiers -rtt, -rttvar, -sendpipe, -recvpipe, -
mtu, -hopcount, -expire, and -ssthresh provide initial values
to metrics maintained in the routing entry. These may be
individually locked by preceding each such modifier to be locked
by the -lock meta-modifier, or one can specify that all ensuing
metrics may be locked by the -lockrest meta-modifier.
The optional modifiers -reject and -blackhole specify route
behavior different from a normal route. A normal route allows
packets to be forwarded out on it. Packets sent to reject routes
are dropped and messages designating the route as unreachable
are sent to the packet originators. Packets sent to blackhole
routes are also dropped, but no notification is sent to the
packet originators. In both cases, you must specify 127.0.0.1
(localhost) as the gateway argument.
The -netmask mask option specifies the subnet mask to use for
the routing entry. Networks that use a nonstandard subnet must
include this option. Specify this option after any optional
modifiers. Do not specify this option if you specify a CIDR
bitmask (/bitmask).
If the flush command is specified, route will flush the routing
tables of all gateway entries. One can choose to flush only
those routes whose destinations are of a given address family by
specifying an optional keyword describing which address family.