Cisco NCS 5500 Series

Sets
In this context, the term set is used in its mathematical sense to mean an unordered collection of unique
elements. The policy language provides sets as a container for groups of values for matching purposes. Sets
are used in conditional expressions. The elements of the set are separated by commas. Null (empty) sets are
allowed.
In the following example:
prefix-set backup-routes
# currently no backup routes are defined
end-set
a condition such as:
if destination in backup-routes then
evaluates as FALSE for every route, because there is no match-condition in the prefix set that it satisfies.
You may want to perform comparisons against a small number of elements, such as two or three community
values, for example. To allow for these comparisons, the user can enumerate these values directly. These
enumerations are referred to as inline sets. Functionally, inline sets are equivalent to named sets, but allow
for simple tests to be inline. Thus, comparisons do not require that a separate named set be maintained when
only one or two elements are being compared. See the set types described in the following sections for the
syntax. In general, the syntax for an inline set is a comma-separated list surrounded by parentheses, where
element-entry is an entry of an item appropriate to the type of usage such as a prefix or a community value.
The following is an example using an inline community set:
route-policy sample-inline
if community matches-any ([10..15]:100) then
set local-preference 100
endif
end-policy
The following is an equivalent example using the named set test-communities:
community-set test-communities
10:100,
11:100,
12:100,
13:100,
14:100,
15:100
end-set
route-policy sample
if community matches-any test-communities then
set local-preference 100
endif
end-policy
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
135
Implementing Routing Policy
Sets