HP ProCurve 2650

15-16
IP Routing Features
Configuring Static IP Routes
Configuring a “Null” Route
You can configure the routing switch 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 routing switch receives a packet destined for the
address, the routing switch 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:
HPswitch(config)# ip route 209.157.22.0 255.255.255.0 reject
HPswitch(config)# write memory
Syntax: ip route <ip-addr> <ip-mask> reject
or
ip route <ip-addr>/<mask-bits> reject
The <ip-addr> parameter specifies the network or host address. The routing
switch will drop packets that contain this address in the destination field
instead of forwarding them.
The <ip-mask> parameter specifies the network mask. Ones are significant
bits and zeros allow any value. For example, the mask 255.255.255.0 matches
on all hosts within the Class C sub-net address specified by <ip-addr>. Alter-
natively, you can specify the number of bits in the network mask. For example,
you can enter 209.157.22.0/24 instead of 209.157.22.0 255.255.255.0.
The reject parameter indicates that this is a null route. You must specify this
parameter to make this a null route.
!Software.book Page 16 Thursday, October 10, 2002 6:10 PM