367Follow these steps to define a community list:To do… Use the command… RemarksEnter system view system-view —Define a basiccommunity listip community-list { basic-comm-list-num | basiccomm-list-name } { deny | permit }[ community-number-list ] [ internet | no-advertise| no-export | no-export-subconfed ] *Define acommunity listDefine anadvancedcommunity listip community-list { adv-comm-list-num | advancedcomm-list-name } { deny | permit }regular-expressionRequired to defineeitherNot defined bydefault.Defining an extended community listYou can define multiple items for an extended community list that is identified by number. Duringmatching, the relation between items is logic OR. If routing information matches one of these items, itpasses the extended community list.Follow these steps to define an extended community list:To do… Use the command… RemarksEnter system view system-view —Define an extendedcommunity listip extcommunity-list ext-comm-list-number { deny |permit } { rt route-target | soosite-of-origin }&<1-16>RequiredNot defined by defaultConfiguring a routing policyA routing policy is used to filter routing information and modify attributes of matching routing information.The match criteria of a routing policy can be configured by referencing the appropriate filters.A routing policy can comprise multiple nodes, and each routing policy node contains the following:• if-match clauses—Define the match criteria that routing information must satisfy. The matchingobjects are some attributes of routing information.• apply clauses—Specify the actions to be taken on routing information that has satisfied the matchcriteria, such as route attribute modification.• continue clauses—Specify the next routing policy node to be matched. With this clause configured,when a route matches the current routing policy node, it continues to match against the specifiednext node in the same routing policy.PrerequisitesBefore configuring this task, you need to configure the filters and routing protocols. You also need todecide on the name of the routing policy and node numbers, match criteria, and attributes to bemodified.Creating a routing policyFollow these steps to create a routing policy:
