Configuring A Route Map For Pbr - HP 7102dl - ProCurve Secure Router Configuration Manual

IP Routing—Configuring RIP, OSPF, BGP, and PBR
Configuring Policy-Based Routing
N o t e
Fast caching will not work in conjunction with PBR.
The ProCurve Secure Router maintains a fast cache for each interface. This
fast cache stores the most recently used routes. When a packet arrives that
can use a route in the fast cache, the route immediately forwards the packet,
rather than placing it in a queue to await its turn to be processed. Currently,
when you enable PBR on an interface, that interface can no longer use fast
caching: the router must process the packet completely to determine if the
route policy applies to it. Therefore, you may notice some decrease in perfor-
mance after you implement PBR.
Depending on your network design, some features of the Secure Router OS
firewall may not work with PBR.
The Secure Router OS firewall monitors sessions between two hosts. If return
traffic arrives on a different interface than the interface used to forward traffic
for the session, the firewall will determine that the session is invalid. When
you implement PBR, the local router sends traffic over an alternate route; you
cannot ensure that remote devices will send return traffic over the same
connection. Therefore, the firewall may interfere with sessions established
using PBR. You should disable the firewall with the no ip firewall command,
entered from the global configuration mode context. If your network requires
a firewall, you should implement it behind the device that uses PBR.

Configuring a Route Map for PBR

You configure PBR policies in a route map, which you then apply to an
interface. The route map applies to traffic that arrives on the interface. You
can apply only one route map to each interface, but you can configure multiple
entries for each route map.
Each route map consists of a series of sequenced route map entries. Each
route map entry is identified by a name and a sequence number. When you
apply the route map to an interface, you apply it as an entire set, which
includes all the route map entries with the same name and different numbers.
In each route map entry, you enter one or more match commands, which
select traffic for PBR. You also enter one or more set commands, which
determine how the selected traffic is routed.
When a packet arrives on an interface, the router begins to process the route
map associated with the interface. The router processes the entries in order,
starting with the entry that has the lowest sequence number. The router stops
processing the set of route map entries as soon as it finds a match for a packet.
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