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Policy-based Routing (PBR)
Policy-based Routing (PBR) allows a switch to make routing decisions based on policies applied to an
interface.
This chapter covers the following topics:
• Overview
Implementing Policy-based Routing with Dell Networking OS
Configuration Task List for Policy-based Routing
Sample Configuration
Overview
When a router receives a packet it normally decides where to forward it based on the destination address
in the packet, which is used to look up an entry in a routing table. However, in some cases, there may be
a need to forward the packet based on other criteria: size, source, protocol type, destination, etc. For
example, a network administrator might want to forward a packet that uses TCP across a different next-
hop than packets using ICMP. In these situations, you can configure a switch route packets according to
a policy applied to interfaces.
Rules for PBR can also be a combination of things:
When the packet comes from this source and wants to go to that destination then route it to this next-
hop or onto that specific interface. This permits routing over different links or towards different networks
even while the destination is the same but depending on where the packet originates.
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