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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.
Policy-based Routing (PBR)
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