8.1 PBR Overview
This section describes the concept of PBR.
IP unicast PBR is a routing mechanism based on user-defined policies rather than the destination
IP addresses of data packets. PBR provides security and load balancing.
8.2 PBR Supported by the AR150/200
The AR150/200 supports packet routing based on the source IP address and packet length of the
packets. Therefore, PBR can flexibly select routes. After a packet arrives, the system forwards
the packet according to PBR. If no PBR is configured, or if PBR is configured but no matching
entry exists, the system forwards the packet according to the Forwarding Information Base (FIB)
table.
The AR150/200 enforces the PBR to only the locally sent protocol packets, such as ICMP and
BGP packets.
NOTE
A traffic policy can be configured on the AR150/200's interface to redirect the data packets of which the
destination address is not the local address. This traffic policy is invalid for the local packets sent to the
CPU. It applies to the following situations:
l
Load balancing: specifies a forwarding path for special packets.
l
Security inspection: redirects certain packets to the firewall.
For details about the redirection configuration, see Configuring Redirection in the
Huawei AR150&200
Series Enterprise Routers Configuration Guide - QoS
.
8.3 Configuring IP Policy-based Routing
By configuring IP unicast PBR, you can ensure that a certain packet is forwarded through a
specified outbound interface.
8.3.1 Establishing the Configuration Task
This section describes the applicable environment, pre-configuration tasks, data preparation, and
configuration procedure for configuring IP unicast PBR.
Applicable Environment
An internal network is connected to an external network through a router. The router has multiple
egresses to the external network. You can use IP unicast PBR on the interface to control some
packets to pass the specified egress of the router.
To perform PBR on the packets generated by the router, you should configure the local PBR.
Pre-configuration Tasks
Before configuring IP unicast PBR, complete the following tasks:
l
Configuring the interface between the router and other devices
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - IP Service
8 IP Unicast PBR Configuration
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