Reference Guide

756 | Policy-based Routing
www.dell.com | support.dell.com
PBR Exceptions (Permit)
Use the command permit to create an exception to a redirect list. Exceptions are used when a forwarding
decision should be based on the routing table rather than a routing policy.
FTOS assigns the first available sequence number to a rule configured without a sequence number and
inserts the rule into the PBR CAM region next to the existing entries. Since the order of rules is important,
ensure that you configure any necessary sequence numbers.
In the following example, the permit statement is never applied because the redirect list covers all source
and destination IP addresses.
ip redirect-list rcl0
seq 5 redirect 2.2.2.2 ip any any
seq 10 permit ip host 3.3.3.3 any
To ensure that the permit statement or PBR exception is effective, use a lower sequence number, as shown
in the following example.
ip redirect-list rcl0
seq 10 permit ip host 3.3.3.3 any
seq 15 redirect 2.2.2.2 ip any any
Note: Starting in release 8.4.1.2, FTOS supports the use of multiple recursive routes with the same
source-address and destination-address combination in a redirect policy on an E-Series ExaScale router.
A recursive route is a route for which the immediate next-hop address is learned dynamically through a
routing protocol and acquired through a route lookup in the routing table.You can configure multiple
recursive routes in a redirect list by entering multiple seq redirect statements with the same source and
destination address and specify a different next-hop IP address. In this way, the recursive routes are used
as different forwarding routes for dynamic failover. If the primary path goes down and the recursive route
is removed from the routing table, the seq redirect statement is ignored and the next statement in the list
with a different route is used.