Policy Framework Configuration Guide - Juniper Networks

Table of Contents
Testing Routing Policies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Example: Testing a Routing Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Routing Policy Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Example: Defining a Routing Policy from BGP to IS-IS . . . . . . . . . . . . . . . . . . . . . . 73
Example: Using Routing Policy to Set a Preference . . . . . . . . . . . . . . . . . . . . . . . . 73
Example: Importing and Exporting Access and Access-Internal Routes in a
Routing Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Example: Exporting Routes to IS-IS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Example: Applying Export and Import Policies to BGP Peer Groups . . . . . . . . . . . 75
Example: Defining a Routing Policy Based on the Number of BGP
Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Example: Applying a Prefix to Routes Learned from a Peer . . . . . . . . . . . . . . . . . . 76
Example: Redistributing BGP Routes with a Specific Community Tag into
IS-IS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Example: Redistributing OSPF Routes into BGP . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Example: Exporting Direct Routes Into IS-IS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Example: Exporting Internal IS-IS Level 1 Routes to Level 2 . . . . . . . . . . . . . . . . . . 77
Example: Exporting IS-IS Level 2 Routes to Level 1 . . . . . . . . . . . . . . . . . . . . . . . . . 78
Example: Assigning Different Forwarding Next-Hop LSPs to Different Destination
Prefixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Example: Grouping Destination Prefixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Example: Grouping Source Prefixes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Example: Grouping Source and Destination Prefixes in a Forwarding Class . . . . . 81
Example: Accepting Routes with Specific Destination Prefixes . . . . . . . . . . . . . . . 82
Example: Accepting Routes from BGP with a Specific Destination Prefix . . . . . . . 82
Example: Using Routing Policy in an ISP Network . . . . . . . . . . . . . . . . . . . . . . . . . 83
Requesting a Single Default Route on the Customer 1 Router . . . . . . . . . . . . 84
Requesting Specific Routes on the Customer 2 Router . . . . . . . . . . . . . . . . . 85
Configuring a Peer Policy on ISP Router 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Configuring Private and Exchange Peers on ISP Router 1 and 2 . . . . . . . . . . . 89
Configuring Locally Defined Static Routes on the Exchange Peer 2
Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Configuring Outbound and Generated Routes on the Private Peer 2
Router . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Chapter 5 Extended Match Conditions Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Configuring AS Path Regular Expressions to Use as Routing Policy Match
Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Configuring AS Path Regular Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Configuring a Null AS Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
How AS Path Regular Expressions Are Evaluated . . . . . . . . . . . . . . . . . . . . . . 101
Copyright © 2010, Juniper Networks, Inc.
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