Cisco NCS 6000 Series

10.0.7.2/32 ge 16 le 24,
10.0.8.0/26 ge 8 le 16
end-set
prefix-set legal-ipv6-prefix-examples
2001:0:0:1::/64,
2001:0:0:2::/64 ge 96,
2001:0:0:2::/64 ge 96 le 100,
2001:0:0:2::/64 eq 100
end-set
The first element of the prefix-set matches only one possible value, 10.0.1.1/32 or the host address 10.0.1.1.
The second element matches only one possible value, 10.0.2.0/24. The third element matches a range of prefix
values, from 10.0.3.0/28 to 10.0.3.255/32. The fourth element matches a range of values, from 10.0.4.0/24 to
10.0.4.240/28. The fifth element matches prefixes in the range from 10.0.5.0/26 to 10.0.5.252/30. The sixth
element matches any prefix of length 28 in the range from 10.0.6.0/28 through 10.0.6.240/28. The seventh
element matches any prefix of length 32 in the range 10.0.[0..255].2/32 (from 10.0.0.2/32 to 10.0.255.2). The
eighth element matches any prefix of length 26 in the range 10.[0..255].8.0/26 (from 10.0.8.0/26 to
10.255.8.0/26).
The following prefix-set consists entirely of invalid prefix match specifications:
prefix-set ILLEGAL-PREFIX-EXAMPLES
10.1.1.1 ge 16,
10.1.2.1 le 16,
10.1.3.0/24 le 23,
10.1.4.0/24 ge 33,
10.1.5.0/25 ge 29 le 28
end-set
Neither the minimum length nor maximum length is valid without a mask length. For IPv4, the minimum
length must be less than 32, the maximum length of an IPv4 prefix. For IPv6, the minimum length must be
less than 128, the maximum length of an IPv6 prefix. The maximum length must be equal to or greater than
the minimum length.
Enhanced Prefix-length Manipulation
The enhanced prefix-length manipulation support in a prefix-set enhances the prefix-range on using ge
semantics in prefix match specifications. This caters to have a single entry that matches prefixes 0.0.0.0/0,
0.0.0.0/1, 0.0.0.0/2, ...., 0.0.0.0/32. The prefix-length can be manipulated with ge semantics as prefix-set
(0.0.0.0/30 ge 0 le 32) that will match all prefixes in the range 0.0.0.0/0 to 0.0.0.3/32. With this, the single
prefix-set entry 0.0.0.0/32 ge 0 le 32 will match prefixes 0.0.0.0/0, 0.0.0.0/1, 0.0.0.0/2, ...., 0.0.0.0/32.
These are prefix ranges with the IPv4 prefix syntax along with corresponding mask length ranges:
• <A.B.C.D>/<len> ge <G> le <L>
• <A.B.C.D>/[<len>..<G>] (if <len> is lesser than <G> )
• <A.B.C.D>/[<G>..<len>] (if <len> is greater than <G> )
• <A.B.C.D>/<len> ge <G>
• <A.B.C.D>/[<len>..<G>] (if <len> is lesser than <G> )
• <A.B.C.D>/[<G>..<len>] (if <len> is greater than <G> )
Routing Configuration Guide for Cisco NCS 6000 Series Routers, IOS XR Release 6.4.x
390
Implementing Routing Policy
Enhanced Prefix-length Manipulation