Configuring the IPv6 IP-Prefix List
The control action for matched IPv6 routes can be flexibly controlled through the configuration of the IPv6 IP-Prefix List.
Context
The IPv6 IP-prefix list is identified by the list name. Each prefix list contains multiple entries. Each entry independently specifies a matching range in the format of network prefixes, and uses the index number for identification.
During the matching, the system checks every entry in turn according to the index number in an ascending order. As long as the routing information matches one entry, the filtering list is passed, and other entries are no longer matched.
Procedure
- Access the system view.
- Configure an IPv6 prefix list.
ip ipv6-prefix ipv6-prefix-name [ index index-number ] { permit | deny } ipv6-address prefix-length [ greater-equal greater-equal-value ] [ less-equal less-equal-value ]
A prefix list is identified by its list name. Each prefix list can include multiple entries. Each entry can independently specify the matching range of a network prefix form and identify it with an index number. For example, the following is a prefix list named abcd:
# ip ipv6-prefix abcd index 10 permit 1:: 64 ip ipv6-prefix abcd index 20 permit 2:: 64
During the matching, the system checks entries identified by the index number in the ascending order. Once an entry meets the condition, it means that all entries pass the IP-prefix filtering. The system does not match other entries.
If all entries are in deny mode, no routes can pass this filtering list. You are recommended to define a permit :: 0 less-equal 128 entry after the multiple entries in the deny mode, thus allowing all the other IPv6 routes to pass the IP-Prefix filtering.
If more than one IP-Prefix entry is defined, at least one entry should be in permit matching mode.