Understanding Route-Based Match Conditions

You can specify known invalid (“bad”) routes to ignore by specifying matches on destination prefixes. When specifying a destination prefix, you can specify an exact match with a specific route, or a less precise match by using match types. You can configure either a common reject action that applies to the entire list, or an action associated with each prefix.

Additionally, you can specify that “good” routes be processed in a particular way. For instance, you can group traffic from specific source or destination addresses into forwarding classes to be processed using the class of service (CoS) feature.

Table 16 lists route list match types.

Table 16: Route List Match Types

Match Type

Match Conditions

exact

The route shares the same most-significant bits (described by prefix-length), and prefix-length is equal to the route's prefix length.

longer

The route shares the same most-significant bits (described by prefix-length), and prefix-length is greater than the route's prefix length.

orlonger

The route shares the same most-significant bits (described by prefix-length), and prefix-length is equal to or greater than the route's prefix length.

prefix-length-range prefix-length2-prefix-length3

The route shares the same most-significant bits (described by prefix-length), and the route's prefix length falls between prefix-length2 and prefix-length3, inclusive.

through destination-prefix

All the following are true:

  • The route shares the same most-significant bits (described by prefix-length) of the first destination prefix.
  • The route shares the same most-significant bits (described by prefix-length) of the second destination prefix for the number of bits in the prefix length.
  • The number of bits in the route's prefix length is less than or equal to the number of bits in the second prefix.

You do not use the through match type in most routing policy configurations. See the Junos Policy Framework Configuration Guide.

upto prefix-length2

The route shares the same most-significant bits (described by prefix-length) and the route's prefix length falls between prefix-length and prefix-length2.

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