Nested Wildcard Apply Policy; Vrf Import Policy Enhancement - Cisco NCS 5500 Series Configuration Manuals

Implementing Routing Policy

Nested Wildcard Apply Policy

The hierarchical constructs of Routing Policy Language (RPL) allows one policy to refer to another policy.
The referred or called policy is known as a child policy. The policy from which another policy is referred is
called calling or parent policy. A calling or parent policy can nest multiple child policies for attachment to a
common set of BGP neighbors. The nested wildcard apply policy allows wildcard (*) based apply nesting.
The wildcard operation permits declaration of a generic apply statement that calls all policies that contain a
specific defined set of alphanumeric characters, defined on the router.
A wildcard is specified by placing an asterisk (*) at the end of the policy name in an apply statement. Passing
parameters to wildcard policy is not supported. The wildcard indicates that any value for that portion of the
apply policy matches.
To illustrate nested wildcard apply policy, consider this policy hierarchy:
route-policy Nested_Wilcard
apply service_policy_customer*
end-policy
route-policy service_policy_customer_a
if destination in prfx_set_customer_a
set extcommunity rt (1:1) additive
endif
end-policy
route-policy service_policy_customer_b
if destination in prfx_set_customer_b then
set extcommunity rt (1:1) additive
endif
end-policy
route-policy service_policy_customer_c
if destination in prfx_set_customer_c then
set extcommunity rt (1:1) additive
endif
end-policy
Here, a single parent apply statement (apply service_policy_customer*) calls (inherits) all child polices that
contain the identified character string "service_policy_customer". As each child policy is defined globally,
the parent dynamically nests the child policies based on the policy name. The parent is configured once and
inherits each child policy on demand. There is no direct association between the parent and the child policies
beyond the wildcard match statement.

VRF Import Policy Enhancement

The VRF RPL based import policy feature provides the ability to perform import operation based solely on
import route-policy, by matching on route-targets (RTs) and other criteria specified within the policy. No
need to explicitly configure import RTs under global VRF-address family configuration mode. If the import
RTs and import route-policy is already defined, then the routes will be imported from RTs configured under
import RT and then follows the route-policy attached at import route-policy.
Use the source rt import-policy command under VRF sub-mode of VPN address-family configuration
mode to enable this feature.
then
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
Nested Wildcard Apply Policy
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