Policy Framework Configuration Guide - Juniper Networks

Junos 10.4 Policy Framework Configuration Guide
Table 22: Match Type Examples (continued)
Prefix
192.168/16
exact
192.168/16
longer
192.168/16
orlonger
192.168/16
upto /24
192.168/16
through
192.168.16/20
192.168/16
prefix length
range
/18 –/20
192.168.0.0/16
Match
–
Match
Match
Match
–
192.168.0.0/17
–
Match
Match
Match
Match
–
192.168.0.0/18
–
Match
Match
Match
Match
Match
192.168.0.0/19
–
Match
Match
Match
Match
Match
192.168.4.0/24
–
Match
Match
Match
–
–
192.168.5.4/30
–
Match
Match
–
–
–
192.168.12.4/30
–
Match
Match
–
–
–
192.168.12.128/32
–
Match
Match
–
–
–
192.168.16.0/20
–
Match
Match
Match
Match
Match
192.168.192.0/18
–
Match
Match
Match
–
Match
192.168.224.0/19
–
Match
Match
Match
–
Match
10.169.1.0/24
–
–
–
–
–
–
10.170.0.0/16
–
–
–
–
–
–
How Route Lists Are Evaluated in Routing Policy Match Conditions
During route list evaluation, the policy framework software compares each route’s source
address with the destination prefixes in the route list. The evaluation occurs in two steps:
1. The policy framework software performs a longest-match lookup, which means that
the software searches for the prefix in the list with the longest length.
The longest-match lookup considers the prefix and prefix length only and not the
match type. The following sample route list illustrates this point:
from {
route-filter 192.168.0.0/14 upto /24 reject;
route-filter 192.168.0.0/15 exact;
}
then accept;
The longest match is the second route-filter, 192.168.0.0/15, which is based on prefix
and prefix length only.
2. Once an incoming route matches a prefix (longest first), the following actions occur:
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