Configuring Policy-Based Routing; Pbr Configuration Guidelines - Cisco WS-CBS3032-DEL Software Configuration Manual

Chapter 39 Configuring IP Unicast Routing

Configuring Policy-Based Routing

You can use policy-based routing (PBR) to configure a defined policy for traffic flows. By using PBR,
you have more control over routing by reducing the reliance on routes derived from routing protocols.
PBR can specify and implement routing policies that allow or deny paths based on:
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You can use PBR to provide equal-access and source-sensitive routing, routing based on interactive
instead of batch traffic, or routing based on dedicated links. For example, you could transfer stock
records to a corporate office on a high-bandwidth, high-cost link for a short time while sending routine
application data such as e-mail over a low-bandwidth, low-cost link.
With PBR, you classify traffic using access control lists (ACLs) and then make traffic go through a
different path. PBR is applied to incoming packets. All packets received on an interface with PBR
enabled are passed through route maps. Based on the criteria defined in the route maps, packets are
forwarded (routed) to the appropriate next hop.
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For more information about configuring route maps, see the
Information" section on page
You can use standard IP ACLs to specify match criteria for a source address or extended IP ACLs to
specify match criteria based on an application, a protocol type, or an end station. The process proceeds
through the route map until a match is found. If no match is found, normal destination-based routing
occurs. There is an implicit deny at the end of the list of match statements.
If match clauses are satisfied, you can use a set clause to specify the IP addresses that identify the next
hop router in the path.
For details about PBR commands and keywords, see the Cisco IOS IP Command Reference, Volume 2 of
3: Routing Protocols, Release 12.2. For a list of PBR commands that are visible but not supported by the
switch, see
PBR configuration is applied to the whole stack, and all switches use the stack-master configuration.
Note This software release does not support Policy-Based Routing (PBR) when processing IPv4 and IPv6
traffic.

PBR Configuration Guidelines

Before configuring PBR, you should be aware of this information:
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OL-13270-06
Identity of a particular end system
Application
Protocol
If packets do not match any route map statements, all set clauses are applied.
If a statement is marked as permit and the packets do not match any route-map statements, the
packets are sent through the normal forwarding channels, and destination-based routing is
performed.
For PBR, route-map statements marked as deny are not supported.
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Appendix B, "Unsupported Commands in Cisco IOS Release 12.2(58)SE."
To use PBR, you must have the IP services feature set enabled on the switch or the stack master.
Multicast traffic is not policy routed. PBR applies to only to unicast traffic.
You can enable PBR on a routed port or on an SVI.
The switch does not support route-map deny statements for PBR.
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
Configuring Protocol-Independent Features
"Using Route Maps to Redistribute Routing
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