Configuring an IP prefix list controls the advertising and receiving of routes based on the destination address. 

You can use the following command to configure the IPv4 prefix list.

set routing prefix-list {ipv4-family <ipv4-prefix-name> | ipv6-family <ipv6-prefix-name>} [seq <sequence-number>] {deny|permit} {prefix <ipv4/prefixlen> [ge <greater-equal-value>] [le <less-equal-value>] | prefix-any}

  • If an IP prefix list is not used together with the match clauses in a routing map, you must set at least one node to the permit mode in the IP prefix list. If no node is set to the permit mode, all routes are filtered out.
  • When configuring IP prefix list, it is strongly recommended to configure sequence number for each IP prefix list node. Otherwise, the precedence of this IP prefix list will be uncertain, and thus the desired IP filtering effect will not be achieved.

The following example configures the IP prefix list named p1 to permit only the routes with the mask length ranging from 8 to 16 on the network segment 35.0.0.0/8.

admin@Xorplus# set routing prefix-list ipv4-family p1 seq 1 permit prefix 35.0.0.0/8 ge 16
admin@Xorplus# commit