Updated on 2024-08-19 GMT+08:00

Creating an AS_Path List

Scenarios

This section describes how to create an AS_Path list.

Notes and Constraints

Each filter in an AS_Path list must have its unique sequence number.

Procedure

  1. Go to the AS_Path Lists page.
  2. Click Create AS_Path List in the upper right corner.

    The Create AS_Path List dialog box is displayed.

  3. Configure the parameters based on Table 1.

    Table 1 Parameters for creating an AS_Path list

    Parameter

    Description

    Example Value

    Name

    Mandatory

    Enter the name of the AS_Path list. The name:
    • Can contain 1 to 64 characters.
    • Can contain letters, digits, underscores (_), hyphens (-), and periods (.).

    asPathFilter-ab

    Description

    Optional

    Enter the description of the AS_Path list in the text box as required.

    -

    AS_Path Filters

    Mandatory

    Configure parameters of the AS_Path filters:
    • Sequence Number: An AS_Path list consists of one or more AS_Path filters that are applied to filter routes based on their sequence numbers, in ascending order. A sequence number can be from 0 to 65535.
    • Action: Select Allow or Deny. If a route matches an AS_Path filter with Action set to Allow, the route is allowed. If the AS_Path filter has Action set to Deny, the route is denied.
    • Regular Expression: A string that describes a characteristic and verifies whether another string conforms to this characteristic. An AS_Path filter defines an AS_Path regular expression to match AS_Path attributes of BGP routes for filtering BGP routes.

      For details, see AS_Path Regular Expressions.

    • Sequence Number: 10
    • Action: Allow
    • Regular Expression: 65+

  4. Click OK.

    On the AS_Path Lists page, you can view the created AS_Path list.

Follow-Up Operations

Creating a Route Policy: An AS_Path list takes effect through a route policy.