Cisco 7604 Configuration Manual page 493

Chapter 33 Configuring Network Security
This example shows how to verify the configuration:
Router# show running-config interface gigabitethernet 4/2
Building configuration...
Current configuration : 114 bytes
!
interface GigabitEthernet4/2
ip address 42.0.0.1 255.0.0.0
ip verify unicast reverse-path
no cdp enable
end
Router# show running-config interface gigabitethernet 4/1
Building configuration...
Current configuration : 114 bytes
!
interface GigabitEthernet4/1
ip address 41.0.0.1 255.0.0.0
ip verify unicast reverse-path (RPF mode on g4/1 also changed to strict-check RPF mode)
no cdp enable
end
Router#
Configuring the Multiple-Path Unicast RPF Check Mode on a PFC3
To configure the multiple-path Unicast RPF check mode on a PFC3, perform this task:
Command
Step 1
Router(config)# mls ip cef rpf multipath {punt |
pass | interface-group}
Router(config)# no mls ip cef rpf multipath {punt
| interface-group}
Step 2
Router(config)# end
Step 3
Router# show mls cef ip rpf
When configuring multiple path RPF check, note the following information:
•
•
•
This example shows how to configure multiple path RPF check:
Router(config)# mls ip cef rpf multipath punt
OL-4266-08
punt (default)—The PFC3 performs the Unicast RPF check in hardware for up to two interfaces per
prefix. Packets arriving on any additional interfaces are redirected (punted) to the MSFC3 for
Unicast RPF check in software.
pass—The PFC3 performs the Unicast RPF check in hardware for single-path and two-path
prefixes. Unicast RPF check is disabled for packets coming from multipath prefixes with three or
more reverse-path interfaces (these packets always pass the Unicast RPF check).
interface-group—The PFC3 performs the Unicast RPF check in hardware for single-path and
two-path prefixes. The PFC3 also performs the Unicast RPF check for up to four additional
interfaces per prefix through user-configured multipath Unicast RPF check interface groups.
Unicast RPF check is disabled for packets coming from other multipath prefixes that have three or
more reverse-path interfaces (these packets always pass the Unicast RPF check).
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
Configuring Unicast Reverse Path Forwarding Check
Purpose
Configures the multiple path RPF check mode on a PFC3.
Returns to the default (mls ip cef rpf multipath punt).
Exits configuration mode.
Verifies the configuration.
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