Configuring a Community Set

Procedure

• Configure a community set using the paragraph editing mode.
  1. Run the edit xpl community-list community-list-name command to enter the community set paragraph editing interface view.
  2. Press i to enter the text editing mode.
     

     Sets or route-filters can be configured only in the text editing mode. If you exit from the text editing mode, you can perform shortcut key operations only.

  3. Configure a start clause (xpl community-list community-list-name) for a community set.
  4. Configure elements in the format of aa:nn (100:1 for example), a community number, or a known community attribute (internet, no-export-subconfed, no-advertise, or no-export) for the community set and separate every two neighboring elements with a comma (,). You can also configure elements in the regular regular-expression format to indicate that the community attribute of a route matches a specified regular expression, and regular-expression specifies a regular expression. An asterisk (*) in an element can be used to match any digit. For example, 100:* indicates that the element matches all community values with the AS number 100.
     

     Regular expression processing is computing-intensive. When a large number of regular expressions are configured in an XPL policy to match a BGP route attribute and the length of the route attribute is long, the processing performance of the XPL policy deteriorates. To improve the processing performance of the routing policy, decrease the number of regular expressions or use a non-regular expression matching command.

     It is recommended that a maximum of 100 regular expressions be configured for each policy.

  5. Configure an end clause (end-list) for the community set.
  6. Press Esc to exit from the text editing mode.
  7. Press :wq and Enter to save the configurations and exit from the global variable set paragraph editing interface view.
     

     A message is displayed for you to confirm whether to commit the configurations when you attempt to exit from the global variable set paragraph editing interface view. To commit the configurations, press Y.

     To exit from the global variable set paragraph editing interface view without saving the configurations, press :q! and Enter.

• Configure a community set using the line editing mode.
  1. Run the system-view command to enter the system view.
  2. Run the xpl community-list community-list-name command to enter the community set view.
  3. Configure elements in the format of aa:nn (100:1 for example), a community number, or a known community attribute (internet, no-export-subconfed, no-advertise, or no-export) for the community set and separate every two neighboring elements with a comma (,). You can also configure elements in the regular regular-expression format to indicate that the community attribute of a route matches a specified regular expression, and regular-expression specifies a regular expression. An asterisk (*) in an element can be used to match any digit. For example, 100:* indicates that the element matches all community values with the AS number 100.
     

     Regular expression processing is computing-intensive. When a large number of regular expressions are configured in an XPL policy to match a BGP route attribute and the length of the route attribute is long, the processing performance of the XPL policy deteriorates. To improve the processing performance of the routing policy, decrease the number of regular expressions or use a non-regular expression matching command.

     It is recommended that a maximum of 100 regular expressions be configured for each policy.

  4. Run the end-list command to conclude the configuration of the community set, exit the community set view, and return to the system view.
  5. Run the commit command to commit the configuration.