Configuring Loose Mode Urpf; Configuring Loose Mode Urpf With The Allow-Self-Ping Option - Cisco 10000-2P2-2DC Software Configuration Manual

Chapter 13 Unicast Reverse Path Forwarding

Configuring Loose Mode uRPF

Example 13-4
Example 13-4 Loose Mode uRPF configuration on 8/1/0 interface
Router# conf t
Enter configuration commands, one per line.
Router (config)# int g8/1/0
Router (config-if)# ip verify unicast source reachable-via?
any Source is reachable via any interface
rx
Router (config-if)# ip verify unicast source reachable-via any?
<1-199>
<1300-2699>
allow-default
allow-self-ping
<cr>
Router (config-if)# ip verify unicast source reachable-via any
Router (config-if)# end
Example 13-5
uRPF has been configured on a router
Example 13-5 Verifying Loose Mode uRPF on 8/1/0 interface
Router# sh ru interface gig8/1/0
!
interface GigabitEthernet8/1/0
ip address 80.1.1.1 255.255.255.0
ip verify unicast source reachable-via any
negotiation auto
end

Configuring Loose Mode uRPF with the allow-self-ping Option

Example 13-6
Example 13-6 Loose Mode uRPF with the allow-self-ping option
Router(config)# int g8/1/0
Router(config-if)# ip verify unicast source reachable-via any allow-self-ping
Router(config-if)# end
Router# sh ru int g8/1/0
!
interface GigabitEthernet8/1/0
ip address 80.1.1.1 255.255.255.0
ip verify unicast source reachable-via any allow-self-ping
negotiation auto
end
OL-2226-23
shows how to enable Loose Mode uRPF on a router over the Gigabit Ethernet Interface:
Source is reachable via interface on which packet was received
IP access list (standard or extended)
IP expanded access list (standard or extended)
Allow default route to match when checking source address
Allow router to ping itself (opens vulnerability in
verification)
shows how you can use the show router interface command for verifying that Loose Mode
shows how you can configure Loose Mode uRPF with the allow-self-ping option.
End with CNTL/Z.
Cisco 10000 Series Router Software Configuration Guide
Configuration Examples of uRPF
13-17