Cisco Cisco Packet Data Gateway (PDG)
Routing
▀ Routing Policies
▄ ASR 5500 System Administration Guide, StarOS Release 17
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Routing Policies
This section describes how to configure the elements needed to define routing policies. Routing policies modify and
redirect routes to and from the system to satisfy specific network deployment requirements.
redirect routes to and from the system to satisfy specific network deployment requirements.
Use the following building blocks to configure routing policies:
Route Access Lists – The basic building block of a routing policy. Route access lists filter routes based on a
range of IP addresses.
IP Prefix Lists – A more advanced element of a routing policy. An IP Prefix list filters routes based on IP
prefixes.
AS Path Access Lists – A basic building block used for Border Gateway Protocol (BGP) routing. These lists
filter Autonomous System (AS) paths.
Route Maps – Route-maps provide detailed control over routes during route selection or route advertisement by
a routing protocol, and in route redistribution between routing protocols. For this level of control you use IP
Prefix Lists, Route Access Lists and AS Path Access Lists to specify IP addresses, address ranges, and
Autonomous System paths.
Prefix Lists, Route Access Lists and AS Path Access Lists to specify IP addresses, address ranges, and
Autonomous System paths.
Creating IP Prefix Lists
Use the following configuration example to create IP Prefix Lists:
config
context context_name
ip prefix-list name list_name { deny | permit } network_address/net_mask
Notes:
Set the IP prefix list to deny, permit or match any prefix.
IPv4 dotted-decimal and IPv6 colon-separated-hexadecimal addresses are supported.
Save your configuration as described in the Verifying and Saving Your Configuration chapter.