Brocade BigIron RX Series Configuration Guide - Manual (Page 282)

204 BigIron RX Series Configuration Guide
53-1002484-04
Configuring forwarding parameters
7
Syntax: ip route <dest-ip-addr> <dest-mask> | <dest-ip-addr>/<mask-bits>
<next-hop-ip-addr> | ethernet <slot/port> | ve <num> | tunnel <num>
[<metric>] [tag <num>] [distance <num>]
The <dest-ip-addr> is the route’s destination. The <dest-mask> is the network mask for the route’s
destination IP address. Alternatively, you can specify the network mask information by entering /
followed by the number of bits in the network mask. For example, you can enter 192.0.0.0
255.255.255.0 as 192.0.0.0/.24.
The <next-hop-ip-addr> is the IP address of the next-hop router (gateway) for the route.
For a default route, enter 0.0.0.0 0.0.0.0 xxx.xxx.xxx.xxx (use 0 for the <mask-bits> if you specify
the address in CIDR format).
If you do not want to specify a next-hop IP address, you can instead specify a port or interface
number on the device. The ve <num> parameter specifies a virtual interface number and tunnel
<num> parameter specifies the tunnel interface number. The <slot/port> is the port’s number of
the device. If you specify an Ethernet port, the device forwards packets destined for the static
route’s destination network to the specified interface. Conceptually, this feature makes the
destination network like a directly connected network, associated with a device interface.
NOTE
The port or virtual interface you use for the static route’s next hop must have at least one IP address
configured on it. The address does not need to be in the same subnet as the destination network.
The <metric> parameter specifies the cost of the route and can be a number from 1 – 16. The
default is 1.
NOTE
If you specify 16, RIP considers the metric to be infinite and thus also considers the route to be
unreachable.
The tag <num> parameter specifies the tag value of the route. Possible values: 0 - 4294967295.
Default: 0.
The distance <num> parameter specifies the administrative distance of the route. When
comparing otherwise equal routes to a destination, the device prefers lower administrative
distances over higher ones, so make sure you use a low value for your default route. Possible
values: 1 - 255. Default: 1.
NOTE
The device will replace the static route if it receives a route with a lower administrative distance.
Refer to
“Changing administrative distances” on page 842 for a list of the default administrative
distances for all types of routes.
Configuring a “null” route
You can configure the device to drop IP packets to a specific network or host address by configuring
a “null” (sometimes called “null0”) static route for the address. When the device receives a packet
destined for the address, the device drops the packet instead of forwarding it.
To configure a null static route to drop packets destined for network 209.157.22.x, enter the
following commands.
BigIron RX(config)# ip route 209.157.22.0 255.255.255.0 null0
BigIron RX(config)# write memory