(Optional) Configuring an if-match Clause
Context
An if-match clause defines matching rules related to route filters and attributes in a routing policy.
If no if-match clause is configured for a node in a routing policy, routes match the routing policy in this node. If one or more if-match clauses are configured in a node, the relationship between the clauses is "AND". This means that a route matches this node only when they match all the if-match clauses in this node. This rule does not apply to if-match as-path-filter, if-match community-filter, if-match extcommunity-filter, if-match interface, or if-match route-type clauses. The relationship between these clauses is "OR", and the relationship between these clauses and other if-match clauses is "AND". For example, if multiple if-match as-path-filter clauses are configured in a node, the relationship between these clauses is "OR", and the relationship between these clauses and other if-match clauses is "AND".
If an if-match clause defines a filter that is not configured, all routes match this if-match clause by default.
The if-match acl and if-match ip-prefix commands cannot be used together in the same node. When both the commands are used in a node, the most recently configured one overrides the previous one.
When modifying the configurations of cooperative routing policies with multiple if-match clauses, it is recommended that you also perform the configuration task of Controlling the Valid Time of Routing Policies. Otherwise, an incomplete routing policy will cause route flapping.
Procedure
- Run system-view
The system view is displayed.
- Run route-policy route-policy-name { permit | deny } node node
The routing policy view is displayed.
- Configure if-match clauses in any sequence for a
routing policy according to your network requirements.
Run if-match acl { acl-number | acl-name }
An if-match clause is configured to match the basic ACL.
Run if-match as-path-filter { as-path-filter-number &<1-16> | as-path-filter-name }
An if-match clause is configured to match AS_Path filters.
- Run either of the following commands as required to configure an if-match clause based on community filters:
- if-match community-filter { basic-comm-filter-num [ whole-match ] | adv-comm-filter-num } &<1-16>
- if-match community-filter comm-filter-name [ whole-match ]
Run if-match extcommunity-filter { { basic-extcomm-filter-num | adv-extcomm-filter-num } &<1-16> | extcomm-filter-name }
An if-match clause is configured to match extended community filters.
Run if-match cost { cost | greater-equal greater-equal-value [ less-equal less-equal-value ] | less-equal less-equal-value }
An if-match clause is configured to match the route cost of routes.
Run if-match interface { interface-type interface-number } &<1-16>
An if-match clause is configured to match the outbound interface of routes.
Run if-match ip { next-hop | route-source | group-address } { acl { acl-number | acl-name } | ip-prefix ip-prefix-name }
An if-match clause is configured to match the next hop or source address of IPv4 routes.
Run if-match ipv6 { address | next-hop | route-source } prefix-list ipv6-prefix-name
An if-match clause is configured to match the destination address, next hop, or source address of IPv6 routes.
Run if-match ip-prefix ip-prefix-name
An if-match clause is configured to match the IP prefix list.
Run if-match rd-filter rd-filter-number
An if-match clause is configured to match the RD filter.
- Run the following command as
required to match the type of route:
Run if-match route-type { external-type1 | external-type1or2 | external-type2 | internal | nssa-external-type1 | nssa-external-type1or2 | nssa-external-type2 }
An if-match clause is configured to match a specified type of OSPF routes.
Run if-match route-type { is-is-level-1 | is-is-level-2 }
An if-match clause is configured to match a specified type of IS-IS routes.
Run if-match tag tag
An if-match clause is configured to match the tag of routes.