Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual page 441

Chapter 30 Configuring Network Security
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 PFC3B
To configure the multiple-path Unicast RPF check mode on a PFC3B, perform this task:
Command
Step 1
Router(config)# mls ip cef rpf mpath {punt | pass
| interface-group}
Router(config)# no mls ip cef rpf mpath {punt |
interface-group}
Step 2
Router(config)# end
Step 3
Router# show mls cef ip rpf
When configuring the multiple path RPF check mode, note the following information:
•
•
•
This example shows how to configure punt as the multiple path RPF check mode:
Router(config)# mls ip cef rpf mpath punt
OL-11439-03
punt mode (default)—The PFC3B 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
PISA for Unicast RPF check in software.
pass mode—The PFC3B 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 mode—The PFC3B performs the Unicast RPF check in hardware for single-path
and two-path prefixes. The PFC3B 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).
Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
Configuring Unicast Reverse Path Forwarding Check
Purpose
Configures the multiple path RPF check mode on a
PFC3B.
Returns to the default (mls ip cef rpf mpath punt).
Exits configuration mode.
Verifies the configuration.
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