Differences between current version and revision by previous author of ReversePathFiltering.
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| Newer page: | version 9 | Last edited on Wednesday, February 28, 2007 5:45:39 pm | by GerwinVanDeSteeg | |
| Older page: | version 8 | Last edited on Wednesday, June 2, 2004 7:50:22 am | by CraigBox | Revert |
@@ -3,12 +3,14 @@
----
!Example
Assume a router with the following routing table
+<?plugin OldStyleTable
|Dest|Mask|Interface
|10.0.0.0|255.0.0.0|eth0
|192.168.0.0|255.255.0.0|eth1
|default|*|eth0
+?>
A packet arriving at eth0 with a source IP address of 10.10.10.2 would not be dropped, as the best route for 10.10.10.2 is out eth0.
A packet arriving at eth0 with a source IP address of 192.168.40.2 would be dropped as the best route for 192.168.40.2 is out eth1, a different interface to what the packet was received on.
@@ -25,18 +27,19 @@
To use RPF your router must support CiscoExpressForwarding.%%%
To enable Reverse Path Forwarding.%%%
-
+<verbatim>
Router#
Router#configure terminal
Router(config)#int <<interface-type>> <<Interface-num>>
Router(config-if)#ip verify unicast reverse-path
Router(config-if)#end
+</verbatim>
To verify the RPF is working%%%
''Look closely at the last three lines''%%%
-
+<verbatim>
Router#show ip interface
<<Interface-type>> <<interface-num>> is up, line protocol is up
Internet address is xxx.xxx.xxx.xxx/xx
Broadcast address is xxx.xxx.xxx.xxx
@@ -45,16 +48,17 @@
BGP Policy Mapping is disabled
__IP verify source reachable-via RX, allow default__
__4 verification drops__
__0 suppressed verification drops__
-
+</verbatim>
See http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter09186a00800ca7d4.html for more details.
-----
!!Configuring RPF on Juniper Routers
To enable Reverse Path Forwarding
+<verbatim>
[[edit]
routing-options {
forwarding-table {
@@ -63,10 +67,11 @@
}
}
+</verbatim>
See http://www.juniper.net/techpubs/software/junos/junos63/swconfig63-routing/html/routing-generic-config11.html for more details.
----
CategoryNetworking
