Example: Configuring a PPPoE Service Name Table

This example shows how you can configure a PPPoE service name table on an MX Series router with service entries that correspond to different client services. By configuring the appropriate actions (delay, terminate, or drop) and agent circuit identifier/agent remote identifier (ACI/ARI) pairs for the service entries, you can provide load balancing and redundancy across a set of remote access concentrators (ACs) in a mesh topology, and determine how best to allocate service requests from PPPoE clients to the servers in your network.

In this example, the PPPoE service name table, Table1, contains the following service entries:

• user1-service—Named service representing the subscriber service for user1.

• user2-service—Named service representing the subscriber service for user2.

• empty service—Represents an unspecified service.

To configure a PPPoE service name table with service entries that correspond to different subscriber services:

1. Create the PPPoE service name table and define the services and associated actions.

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   [edit protocols pppoe]
   service-name-tables Table1 {
       service empty {
           drop;
       }
       service user1-service {
           terminate;
           agent-specifier {
               aci “east*” ari “wfd*” delay 10;
               aci “west*” ari “svl*” delay 10;
           }
       }
       service user2-service {
           delay 20;
       }
   }
   

   This example creates a PPPoE service name table named Table1 with three service entries, as follows:

   • The empty service is configured with the drop action. This action prohibits the router (AC) from responding to PADI packets from the client that contain empty service name tags.

   • The user1-service named service is configured with both the terminate action, and two ACI/ARI (agent-specifier) pairs:

     • The terminate action directs the router to immediately respond to PADI packets from the client that contain the user1-service tag, and is the default action for named services.

     • The 10-second delay configured for each ACI/ARI pair applies only to PADI packets from the client that contains a vendor-specific tag with matching ACI and ARI information. In this example, configuring the delay action indicates that the east or west server is considered the backup AC for handling these client requests, and that you expect an AC other than east or west to handle the request as the primary server. If the primary AC does not respond to the client with a PADO packet within 10 seconds, then the east or west backup AC sends the PADO packet after the 10-second delay expires.

   • The user2-service named service is configured with a 20-second delay, indicating that you expect an AC other than the one on which this PPPoE service name table is configured to be the primary AC for handling this client request. If the primary AC does not respond to the client with a PADO packet within 20 seconds, then the backup AC (that is, the router on which you are configuring the service name table) sends the PADO packet after the 20-second delay expires.

2. Assign the PPPoE service name table to a PPPoE underlying interface configured with PPPoE encapsulation.

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   [edit interfaces]
   ge-2/0/3 {
       vlan-tagging;
       unit 0 {
           vlan-id 100;
           encapsulation ppp-over-ethernet;
           pppoe-underlying-options {
               service-name-table Table1;
           }
       }
   }
   

3. (Optional) Verify the PPPoE service name table configuration.

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   user@host> show pppoe service-name-tables Table1
   Service Name Table: Table1
     Service Name: <empty>
     Service Action: Drop
   
     Service Name: user1–service
     Service Action: Terminate
       ACI: east*
       ARI: wfd*
         ACI/ARI Action: Delay 10 seconds
       ACI: west*
       ARI: svl*
         ACI/ARI Action: Delay 10 seconds
   
     Service Name: user2–service
     Service Action: Delay 20 seconds

4. (Optional) Verify whether the PPPoE service name table has been properly assigned to the underlying PPPoE interface, and whether packet transfer between the router (AC) and PPPoE client is working correctly.

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   user@host>show pppoe underlying-interfaces ge-2/0/3.0 extensive
   ge-2/0/3.0 Index 72
     State: Static, Dynamic Profile: None,
     Max Sessions: 4000, Active Sessions: 2,
     Service Name Table: Table1, Duplicate Protection: Off,
     AC Name: east
     PacketType                       Sent         Received
       PADI                              0                2
       PADO                              2                0
       PADR                              0                2
       PADS                              2                0
       PADT                              0                1
       Service name error                0                0
       AC system error                   0                0
       Generic error                     0                0
       Malformed packets                 0                0
       Unknown packets                   0                0

   Examine the command output to ensure the following:

   • The Service Name Table field displays the name of the correct PPPoE service name table. This field displays none if no service name table has been associated with the specified interface.

   • The Sent and Received values for the Service name error field are 0 (zero). For example, a nonzero value in the Received field for Service name error indicates that there are errors in the control packets received from PPPoE clients, such as a PADI packet that does not contain a service name tag.