Chapter 21: Policy-Based Routing; Policy-Based Routing - Avaya G430 Manual

Chapter 21: Policy-based routing

Policy-based routing

Policy-based routing enables you to configure a routing scheme based on traffic's source IP
address, destination IP address, IP protocol, and other characteristics. You can use policy-
based routing (PBR) lists to determine the routing of packets that match the rules defined in
the list. Each PBR list includes a set of rules, and each rule includes a next hop list. Each next
hop list contains up to 20 next hop destinations to which the Branch Gateway sends packets
that match the rule. A destination can be either an IP address or an interface.
Policy-based routing takes place only when the packet enters the interface, not when it leaves.
Policy-based routing takes place after the packet is processed by the Ingress Access Control
List and the Ingress QoS list. Thus, the PBR list evaluates the packet after the packet's DSCP
field has been modified by the Ingress QoS List. See
Note:
The Loopback 1 interface is an exception to this rule. On the Loopback 1 interface, PBR
lists are applied when the packet leaves the interface. This enables the PBR list to handle
packets sent by the Branch Gateway device itself, as explained below.
Note:
ICMP keepalive provides the interface with the ability to determine whether a next hop is or
is not available. See
Note:
Policy-based routing is supported on IPv4 only.
Policy-based routing only operates on routed packets. Packets traveling within the same
subnet are not routed, and are, therefore, not affected by policy-based routing.
The Loopback interface is a logical interface which handles traffic that is sent to and from the
Branch Gateway itself. This includes ping packets to or from the Branch Gateway, as well as
Telnet, SSH, FTP, DHCP Relay, TFTP, HTTP, NTP, SNMP, H.248, and other types of traffic.
The Loopback interface is also used for traffic to and from analog and DCP phones connected
to the device via IP phone entities.
Administering Avaya G430 Branch Gateway
ICMP keepalive on page 277.
Policy lists to packets
October 2013
on page 565.
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