IP Prefix List

About this task

IP prefix lists are a convenient way to filter networks in BGP supported networks. IP prefix lists work similarly to access lists. A prefix list contains ordered entries processed sequentially. Like access lists, the evaluation of a prefix against a prefix list ends as soon as a match is found.

To restrict the routing information advertised, use filters consisting of an IP prefix list applied to updates both to and from neighbors.

To define an IP prefix list:

Procedure

  1. Select ConfigurationNetworkBGPIP Prefix List.
    Click to expand in new window
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  2. Select Add to create a new IP prefix list or Edit to modify the attributes of a selected list. Existing policies can be copied or renamed as needed.
    Click to expand in new window
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  3. Define the following IP Prefix List settings:
    Sequence Supply a sequence number to determine the prefix utilization order for existing lists.
    IP Prefix Set the IP prefix used as an prefix list rule.
    Greater Than Specify a greater than or equal to value for an IP prefix range.
    Less Than Specify a less than or equal to value for an IP prefix range.
    Allow Use the drop-down menu to set a Permit or Deny designation to the rule configuration.
  4. Click OK to save the changes, Reset to revert to the last saved configuration or Exit to close the screen.