Example: Configuring a Static PPPoE Subscriber Interface over ATM

This example illustrates a Point-to-Point Protocol over Ethernet (PPPoE) over ATM configuration that creates a static PPPoE (pp0) subscriber interface over a static ATM underlying interface on an MX Series router. The router must have Module Port Concentrator/Modular Interface Card (MPC/MIC) interfaces that use an ATM MIC with small form-factor pluggable transceiver (SFP).

Note: You can also configure a dynamic PPPoE interface over a static ATM underlying interface on an MX Series router with an ATM MIC with SFP installed. For information, see Example: Configuring a Dynamic PPPoE Subscriber Interface over ATM.

Requirements

• Junos OS Release 12.2
• MX Series 3D Universal Edge Router
• ATM MIC with SFP (Model Number MIC-3D-8OC3-2OC12-ATM) and compatible MPC1 or MPC2

1. Make sure the MX Series router you are using has an ATM MIC with SFP installed and operational.
   • For information about compatible MPCs for the ATM MIC with SFP, see the MX Series 3D Universal Edge Routers Line Card Guide .
   • For information about installing MPCs and MICs in an MX Series router, see the Hardware Guide for your MX Series router model.
2. Make sure you understand how to configure and use static ATM interfaces.

   See ATM Interfaces Overview.

Overview

By using the ATM MIC with SFP and a supported MPC, you can configure an MX Series router to support static PPPoE subscriber access over an ATM network using ATM Adaptation Layer 5 (AAL5) permanent virtual connections (PVCs). PPPoE-over-ATM configurations on MX Series routers consist of one or more statically created PPPoE (pp0) logical subscriber interfaces over a static ATM underlying interface. Most PPPoE and subscriber services features supported on terminated connections and tunneled (L2TP access concentrator, or LAC) connections are also supported for PPPoE-over-ATM connections on an MX Series router.

1. Statically configure ATM physical interface at-1/0/6 with virtual path identifier (VPI) 6.
2. Statically configure logical unit 2 on the ATM physical interface (at-1/0/6.2) with the following properties:
   • PPPoE-over-ATM logical link control (LLC) encapsulation (ppp-over-ether-over-atm-llc)
   • Virtual circuit identifier (VCI) 2 on VPI 6. The combination of VPIs and VCIs provisions the ATM AAL5 PVC for access over the ATM network.
   • (Optional) PPPoE-specific options at the [edit interfaces interface-name unit logical-unit-number family pppoe] hierarchy level

     Note: For dynamic or static PPPoE-over-ATM configurations on MX Series routers, You must specify PPPoE-specific options in the family pppoe stanza at the [edit interfaces interface-name unit logical-unit-number] hierarchy level. Specifying PPPoE-specific options in the pppoe-underlying-options stanza at the [edit interfaces interface-name unit logical-unit-number] hierarchy level is not supported for these configurations.

3. Statically configure the pp0 logical subscriber interface (pp0.2) with at least the following properties:
   • The name of the underlying ATM interface (at-1/0/6.2)
   • The server statement, which configures the router to act as a PPPoE server
   • The unnumbered address (lo0.0) for the inet (IPv4) or inet6 (IPv6) protocol family

   In static PPPoE-over-ATM configurations, each pp0 logical interface configured at the [edit interfaces pp0 unit logical-unit-number] hierarchy level corresponds to a static PPPoE subscriber interface.

Configuration

To configure a static PPPoE subscriber interface over an underlying ATM interface, perform these tasks:

• Configuring the ATM Physical Interface
• Configuring Encapsulation, VCI, and PPPoE Options on Logical Unit 2
• Configuring the Static PPPoE Subscriber Interface

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them in a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

Configuring the ATM Physical Interface

Step-by-Step Procedure

1. Specify that you want to configure ATM-specific options on the physical interface.
   [edit interfaces at-1/0/6]user@host# edit atm-options
2. Configure one or more VPIs on the physical interface.
   [edit interfaces at-1/0/6 atm-options]user@host# set vpi 6

Results

From the [edit] hierarchy level in configuration mode, confirm the results of the ATM physical interface configuration by issuing the show interfaces at-1/0/6 command. If the output does not display the intended configuration, repeat the instructions in this example to correct it.

If you are done configuring the ATM physical interface, enter commit from configuration mode.

Configuring Encapsulation, VCI, and PPPoE Options on Logical Unit 2

Step-by-Step Procedure

1. Configure PPPoE-over-ATM LLC encapsulation on the interface.
   [edit interfaces at-1/0/6 unit 2]user@host# set encapsulation ppp-over-ether-over-atm-llc
2. Configure the VCI for the logical interface.
   [edit interfaces at-1/0/6 unit 2]user@host# set vci 6.2

   This statement configures VCI 2 on VPI 6.

3. Specify that you want to configure the PPPoE protocol family.
   [edit interfaces at-1/0/6 unit 2]user@host# edit family pppoe
4. Configure additional PPPoE-specific options for the dynamic subscriber interface.
   [edit interfaces at-1/0/6 unit 2 family pppoe]user@host# set duplicate-protectionuser@host# set short-cycle-protection lockout-time-min 120 lockout-time-max 240user@host# set max-sessions 3user@host# set max-sessions-vsa-ignoreuser@host# set access-concentrator ac-pppoeoa

Results

From the [edit] hierarchy level in configuration mode, confirm the results of the configuration on logical unit 2 by issuing the show interfaces at-1/0/6.2 command. If the output does not display the intended configuration, repeat the instructions in this example to correct it.

If you are done configuring logical unit 2, enter commit from configuration mode.

Configuring the Static PPPoE Subscriber Interface

Step-by-Step Procedure

1. Specify that you want to configure the pp0 subscriber interface on logical unit 2.
   [edit]user@host# edit interfaces pp0 unit 2
2. Specify that you want to configure PPP options for the subscriber interface.
   [edit interfaces pp0 unit 2]user@host# edit ppp-options
3. Configure Challenge Handshake Authentication Protocol (CHAP) authentication for the subscriber interface.
   [edit interfaces pp0 unit 2 ppp-options]user@host# set chapuser@host# up
4. Specify that you want to configure PPPoE-specific options.
   [edit interfaces pp0 unit 2]user@host# edit pppoe-options
5. Associate the PPPoE subscriber interface with the underlying ATM interface.
   [edit interfaces pp0 unit 2 pppoe-options]user@host# set underlying-interface at-1/0/6.2
6. Configure the router to act as a PPPoE server, also known as a remote access concentrator.
   [edit interfaces pp0 unit 2 pppoe-options]user@host# set serveruser@host# up
7. Configure the interval for sending keepalive requests.
   [edit interfaces pp0 unit 2]user@host# set keepalives interval 10
8. Specify that you want to configure the IPv4 (inet) protocol family.
   [edit interfaces pp0 unit 2]user@host# edit family inet
9. Configure the unnumbered address for the protocol family.
   [edit interfaces pp0 unit 2 family inet]user@host# set unnumbered-address lo0.0

Results

From the [edit] hierarchy level in configuration mode, confirm the results of the static PPPoE subscriber interface configuration by issuing the show interfaces pp0 command. If the output does not display the intended configuration, repeat the instructions in this example to correct it.

If you are done configuring the static PPPoE subscriber interface, enter commit from configuration mode.

Verification

To confirm that the static PPPoE subscriber interface pp0.2 is properly configured on ATM underlying interface at-1/0/6.2, perform the following tasks:

• Verifying the ATM Physical Interface Configuration
• Verifying the Encapsulation, VCI, and PPPoE Options Configuration on Logical Unit 2
• Verifying the Static PPPoE Subscriber Interface Configuration
• Verifying the PPPoE Underlying Interface Configuration

Verifying the ATM Physical Interface Configuration

Purpose

Verify that ATM physical interface at-1/0/6 is properly configured for use with ATM PVCs.

Action

From operational mode, issue the show interfaces at-1/0/6 command.

For brevity, this show command output includes only the configuration that is relevant to the at-1/0/6 physical interface. Any other configuration on the system has been replaced with ellipses (...).

Physical interface: at-1/0/6, Enabled, Physical link is Down
  Interface index: 179, SNMP ifIndex: 598
  Link-level type: ATM-PVC, MTU: 2048, Clocking: Internal, SDH mode, Speed: OC3, Loopback: None, Payload scrambler: Enabled
  Device flags   : Present Running Down
  Link flags     : None
  CoS queues     : 8 supported, 8 maximum usable queues
  Schedulers     : 0
  Current address: 00:1f:12:bc:4a:9b
  Last flapped   : 2012-09-19 07:57:59 PDT (07:46:56 ago)
  Input rate     : 0 bps (0 pps)
  Output rate    : 0 bps (0 pps)
  SDH   alarms   : LOL, LOS
  SDH   defects  : LOL, LOS, LOP, BERR-SF, HP-FERF    
    VPI 6
      Flags: Active
      Total down time: 0 sec, Last down: Never
  Traffic statistics:
         Input  packets:                    0
         Output packets:                    0
...

Meaning

ATM-PVC in the Link-level Type field indicates that encapsulation for ATM permanent virtual circuits is being used on ATM physical interface at-1/0/6. The Active flag for VPI 6 indicates that the virtual path is up and operational.

Verifying the Encapsulation, VCI, and PPPoE Options Configuration on Logical Unit 2

Purpose

Verify that the encapsulation, VCI, and PPPoE settings have been properly configured on logical unit 2 (at-1/0/6.2).

Action

From operational mode, issue the show interfaces at-1/0/6.2 command.

  Logical interface at-1/0/6.2 (Index 345) (SNMP ifIndex 1990)
    Flags: Device-Down Point-To-Point SNMP-Traps 0x4000 Encapsulation: PPPoE-over-ATM-LLC
    Input packets : 0
    Output packets: 0
    Protocol pppoe
      Dynamic Profile: None,
      Service Name Table: None,
      Max Sessions: 3, Max Sessions VSA Ignore: On,
      Duplicate Protection: On, Short Cycle Protection: mac-address,
      AC Name: ac-pppoeoa
    VCI 6.2
      Flags: Active
      Total down time: 0 sec, Last down: Never
        Input packets : 0
        Output packets: 0

Meaning

PPPoE-over-ATM-LLC in the Encapsulation field indicates that logical interface at-1/0/6.2 is properly configured for PPPoE-over-ATM LLC encapsulation. Protocol pppoe indicates that the PPPoE protocol family has been properly configured on the logical interface. The Active flag for VCI 6.2 indicates that VCI 2 on VPI 6 is up and operational.

Verifying the Static PPPoE Subscriber Interface Configuration

Purpose

Verify that the static PPPoE subscriber interface (pp0.2) is properly configured.

Action

From operational mode, issue the show interfaces pp0 command.

Physical interface: pp0, Enabled, Physical link is Up
  Interface index: 131, SNMP ifIndex: 505
  Type: PPPoE, Link-level type: PPPoE, MTU: 1532
  Device flags   : Present Running
  Interface flags: Point-To-Point SNMP-Traps
  Link type      : Full-Duplex
  Link flags     : None

  Logical interface pp0.2 (Index 360) (SNMP ifIndex 1991)
    Flags: Hardware-Down Point-To-Point SNMP-Traps 0x4000 Encapsulation: PPPoE
    PPPoE:
      State: SessionDown, Session ID: None,
      Underlying interface: at-1/0/6.2 (Index 345)
    Input packets : 0
    Output packets: 0
  Keepalive settings: Interval 10 seconds, Up-count 1, Down-count 3
  LCP state: Not-configured
  NCP state: inet: Not-configured, inet6: Not-configured, iso: Not-configured, mpls: Not-configured
  CHAP state: Closed
  PAP state: Closed
    Protocol inet, MTU: 1492
      Flags: Sendbcast-pkt-to-re, Protocol-Down
      Addresses, Flags: Dest-route-down Is-Preferred Is-Primary
        Destination: 100.0.0/24, Local: 100.0.0.1

Meaning

PPPoE in the Link-level type field indicates that PPPoE encapsulation is in use on the pp0 physical interface. PPPoE in the Encapsulation field indicates that PPPoE encapsulation is also in use on the pp0.2 logical subscriber interface. The Underlying interface field indicates that at-1/0/6.2 is properly configured as the underlying interface for the static PPPoE subscriber interface. Protocol inet indicates that the IPv4 protocol family is properly configured on the pp0.2 logical subscriber interface.

Verifying the PPPoE Underlying Interface Configuration

Purpose

Verify that the underlying interface is properly configured for static PPPoE-over-ATM subscriber access.

Action

From operational mode, issue the show pppoe underlying-interfaces at-1/0/6.2 extensive command.

at-1/0/6.2 Index 345
  State: Static, Dynamic Profile: None,
  Max Sessions: 3, Max Sessions VSA Ignore: On,
  Active Sessions: 0,
  Service Name Table: None,
  Duplicate Protection: On, Short Cycle Protection: mac-address,
  AC Name: ac-pppoeoa,
  PacketType                       Sent         Received
    PADI                              0                0
    PADO                              0                0
    PADR                              0                0
    PADS                              0                0
    PADT                              0                0
    Service name error                0                0
    AC system error                   0                0
    Generic error                     0                0
    Malformed packets                 0                0
    Unknown packets                   0                0
  Lockout Time (sec):  Min: 120, Max: 240
    Total clients in lockout: 0
    Total clients in lockout grace period: 0

Meaning

This command indicates that ATM logical interface at-1/0/6.2 is properly configured as the PPPoE underlying interface. Static in the State field indicates that at-1/0/0/.2 is statically configured. The remaining fields display information about the PPPoE-specific interface options configured for the PPPoE underlying interface at the [edit interfaces at-1/0/6 unit 2 family pppoe] hierarchy level. The Lockout Time fields, which appear in this command only when you display the extensive level of output, show the minimum lockout time (120 seconds) and maximum lockout time (240 seconds) configured for the PPPoE underlying interface.