Table Of Contents

PPP over Ethernet Client

Contents

Restrictions for PPPoE Client

Information About PPPoE Client

PPPoE Client Network Topology

PPPoE Client Support on ATM PVCs and Ethernet Interfaces

PPPoE Client Session Initiation

Benefits of the PPPoE Client Feature

How to Configure a PPPoE Client

Configuring a PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T

Enabling PPPoE in a VPDN Group

Configuring a PPPoE Client on an ATM PVC

Configuring a PPPoE Client on an Ethernet Interface

Configuring the Dialer Interface

Clearing PPPoE Client Sessions

Verifying the PPPoE Client

Troubleshooting PPPoE Client Sessions

Configuring a PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases

Configuring a PPPoE Client on an ATM PVC

Configuring a PPPoE Client on an Ethernet Interface

Configuring the Dialer Interface

Clearing PPPoE Client Sessions

Verifying the PPPoE Client

Troubleshooting PPPoE Client Sessions

Configuration Examples for PPPoE Client

PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T: Examples

PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases: Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

clear vpdn tunnel

pppoe-client dial-pool-number

PPP over Ethernet Client

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The PPP over Ethernet Client feature provides PPP over Ethernet (PPPoE) client support on routers on customer premises.

History for the PPP over Ethernet Client Feature

Release	Modification
12.2(2)T	This feature was introduced.
12.2(13)T	PPPoE client functionality was separated from VPDN functionality, resulting in changes to PPPoE client configuration.

Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Contents

•Restrictions for PPPoE Client

•Information About PPPoE Client

•How to Configure a PPPoE Client

•Configuration Examples for PPPoE Client

•Additional References

Restrictions for PPPoE Client

For PPPoE over ATM, one PVC will support only one PPPoE client. Multiple PPPoE clients can run concurrently on different PVCs, but each PPPoE client must use a separate dialer interface and a separate dialer pool.

For PPPoE over Ethernet, each PPPoE client must use a separate dialer interface and a separate dialer pool.

Information About PPPoE Client

Before you configure a PPPoE client, you should understand the following concepts:

•PPPoE Client Network Topology

•PPPoE Client Support on ATM PVCs and Ethernet Interfaces

•PPPoE Client Session Initiation

•Benefits of the PPPoE Client Feature

PPPoE Client Network Topology

The PPP over Ethernet Client feature provides PPPoE client support on routers on customer premises. Before the introduction of this feature, Cisco IOS software supported PPPoE on the access server side only. Figure 1 shows the typical network topology for PPPoE client deployment.

Figure 1 Typical Network Topology for PPPoE Deployment

PPPoE Client Support on ATM PVCs and Ethernet Interfaces

The PPPoE Client feature provides PPPoE client support on ATM permanent virtual circuits (PVCs) and Ethernet interfaces. A dialer interface must be used for cloning virtual access.

One ATM PVC will support one PPPoE client. Multiple PPPoE clients can run concurrently on different PVCs, but each PPPoE client must use a separate dialer interface and a separate dialer pool.

Multiple PPPoE client sessions can be configured on an Ethernet interface, but each session must use a separate dialer interface and a separate dialer pool.

PPPoE Client Session Initiation

A PPPoE session is initiated by the PPPoE client. If the session has a timeout or is disconnected, the PPPoE client will immediately attempt to reestablish the session.

The following four steps describe the exchange of packets that occurs when a PPPoE client initiates a PPPoE session:

1. The client broadcasts a PPPoE Active Discovery Initiation (PADI) packet.

2. When the access concentrator receives a PADI that it can serve, it replies by sending a PPPoE Active Discovery Offer (PADO) packet to the client.

3. Because the PADI was broadcast, the host may receive more than one PADO packet. The host looks through the PADO packets it receives and chooses one. The choice can be based on the access concentrator name or on the services offered. The host then sends a single PPPoE Active Discovery Request (PADR) packet to the access concentrator that it has chosen.

4. The access concentrator responds to the PADR by sending a PPPoE Active Discovery Session-confirmation (PADS) packet. At this point a virtual access interface is created that will then negotiate PPP, and the PPPoE session will run on this virtual access.

If a client does not receive a PADO for a preceding PADI, the client sends out a PADI at predetermined intervals. That interval length is doubled for every successive PADI that does not evoke a response, until the interval reaches a configured maximum.

If PPP negotiation fails or the PPP line protocol is brought down for any reason, the PPPoE session and the virtual access will be brought down. When the PPPoE session is brought down, the client waits for a predetermined number of seconds before trying again to establish a PPPoE.

Benefits of the PPPoE Client Feature

PPPoE is a commonly used application in the deployment of digital subscriber lines (DSL). The PPP over Ethernet Client feature expands PPPoE functionality by providing support for PPPoE on the client as well as on the server.

How to Configure a PPPoE Client

This section contains the following procedures:

•Configuring a PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T

•Configuring a PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases

Configuring a PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T

Perform the following tasks to configure a PPPoE client in releases prior to Cisco IOS release 12.2(13)T:

•Enabling PPPoE in a VPDN Group

•Configuring a PPPoE Client on an ATM PVC

•Configuring a PPPoE Client on an Ethernet Interface

•Configuring the Dialer Interface

•Clearing PPPoE Client Sessions

•Verifying the PPPoE Client

•Troubleshooting PPPoE Client Sessions

Enabling PPPoE in a VPDN Group

Perform this task to enable PPPoE in a virtual private dial-up network (VPDN) group.

Restrictions

This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

SUMMARY STEPS

1. enable

2. configure terminal

3. vpdn enable

4. vpdn-group name

5. request-dialin

6. protocol pppoe

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	vpdn enable Example: Router(config)# vpdn enable	Enables virtual private dialup networking.
Step 4	vpdn-group name Example: Router(config)# vpdn-group group1	Associates a VPDN group with a customer or VPDN profile.
Step 5	request-dialin Example: Router(config-vpdn)# request-dialin	Creates a request-dialin VPDN subgroup.
Step 6	protocol pppoe Example: Router(config-vpdn-req-in)# protocol pppoe	Enables the VPDN subgroup to establish PPPoE sessions.

Configuring a PPPoE Client on an ATM PVC

Perform this task to configure a PPPoE client on an ATM PVC.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface atm number

4. pvc [name] vpi/vci

5. pppoe-client dial-pool-number number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface atm number Example: Router(config)# interface atm 0	Configures an ATM interface.
Step 4	pvc [name] vpi/vci Example: Router(config-if)# pvc 1/100	Creates an ATM PVC.
Step 5	pppoe-client dial-pool-number number Example: Router(config-if-atm-vc)# pppoe-client dial-pool-number 1	Configures the PPPoE client and specifies the dialer interface to use for cloning on the PVC.

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Note If commands are added to the PVC configuration after the PPPoE client session is established, the session is automatically terminated and reestablished.

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Configuring a PPPoE Client on an Ethernet Interface

Perform this task to configure a PPPoE client on an Ethernet interface.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface ethernet number

4. pppoe-client dial-pool-number number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface ethernet number Example: Router(config)# interface ethernet 0	Configures an Ethernet interface.
Step 4	pppoe-client dial-pool-number number Example: Router(config-if)# pppoe-client dial-pool-number 1	Configures the PPPoE client and specifies the dialer interface to use for cloning.

Configuring the Dialer Interface

Perform this task to configure the dialer interface to be used for cloning on the PVC.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface dialer number

4. mtu bytes

5. ip address negotiated

6. dialer pool number

7. dialer-group group-number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface dialer number Example: Router(config)# interface dialer 1	Configures a dialer interface.
Step 4	mtu bytes Example: Router(config-if) mtu 1492	Adjusts the maximum packet size or maximum transmission unit (MTU) size. Note It is recommended that you set the MTU to 1492 bytes. This value accommodates a PPPoE header encapsulation of 8 bytes in the Ethernet frame payload
Step 5	ip address negotiated Example: Router(config-if)# ip address negotiated	Specifies that the IP address for the interface be obtained via PPP/IP Control Protocol (PPP/IPCP) address negotiation.
Step 6	dialer pool number Example: Router(config-if)# dialer pool 1	Specifies the dialing pool to use to connect to a specific destination subnetwork.
Step 7	dialer-group group-number Example: Router(config-if)# dialer-group 1	Configures an interface to belong to a specific dialing group.

Clearing PPPoE Client Sessions

Perform this task to clear PPPoE client sessions.

Restrictions

This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

SUMMARY STEPS

1. enable

2. clear vpdn tunnel pppoe

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	clear vpdn tunnel pppoe Example: Router# clear vpdn tunnel pppoe	Terminates the PPPoE client session and causes the PPPoE client to try immediately to reestablish the session.

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Note To permanently terminate a PPPoE client session, use the no pppoe-client dial-pool-number command in interface configuration mode or interface-atm-vc configuration mode.

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Verifying the PPPoE Client

Perform this task to verify PPPoE client configuration.

Prerequisites

This task assumes that the PPPoE client has been configured.

SUMMARY STEPS

1. enable

2. show vpdn

3. show vpdn session packet

4. show vpdn session all

5. show vpdn tunnel

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	show vpdn Example: Router# show vpdn	Displays information about active Layer 2 Forwarding (L2F) protocol tunnel and L2F message identifiers in a VPDN.
Step 3	show vpdn session packet Example: Router# show vpdn session packet	Displays PPPoE session statistics.
Step 4	show vpdn session all Example: Router# show vpdn session all	Displays PPPoE session information for each session ID.
Step 5	show vpdn tunnel Example: Router# show vpdn tunnel	Displays PPPoE session count for the tunnel.

Troubleshooting PPPoE Client Sessions

Perform this task to troubleshoot the PPPoE client.

Restrictions

This task applies only to releases prior to Cisco IOS Release 12.2(13)T.

SUMMARY STEPS

1. enable

2. debug vpdn pppoe-data

3. debug vpdn pppoe-errors

4. debug vpdn pppoe-events

5. debug vpdn pppoe-packets

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	debug vpdn pppoe-data Example: Router# debug vpdn pppoe-data	Displays PPPoE session data packets.
Step 3	debug vpdn pppoe-errors Example: Router# debug vpdn pppoe-errors	Displays PPPoE protocol errors that prevent a session from being established or errors that cause an established session to be terminated.
Step 4	debug vpdn pppoe-events Example: Router# debug vpdn pppoe-events	Displays PPPoE protocol messages about events that are part of normal session establishment or shutdown.
Step 5	Router# debug vpdn pppoe-packets Example: Router# debug vpdn pppoe-packets	Displays each PPPoE protocol packet exchanged.

Configuring a PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases

Perform the following tasks to configure a PPPoE client in Cisco IOS Release 12.2(13)T or later releases:

•Configuring a PPPoE Client on an ATM PVC

•Configuring a PPPoE Client on an Ethernet Interface

•Configuring the Dialer Interface

•Clearing PPPoE Client Sessions

•Verifying the PPPoE Client

•Troubleshooting PPPoE Client Sessions

Configuring a PPPoE Client on an ATM PVC

Perform this task to configure a PPPoE client on an ATM PVC.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface atm number

4. pvc [name] vpi/vci

5. pppoe-client dial-pool-number number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface atm number Example: Router(config)# interface atm 0	Configures an ATM interface.
Step 4	pvc [name] vpi/vci Example: Router(config-if)# pvc 1/100	Creates an ATM PVC.
Step 5	pppoe-client dial-pool-number number Example: Router(config-if-atm-vc)# pppoe-client dial-pool-number 1	Configures the PPPoE client and specifies the dialer interface to use for cloning on the PVC.

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Note If commands are added to the PVC configuration after the PPPoE client session is established, the session is automatically terminated and reestablished.

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Configuring a PPPoE Client on an Ethernet Interface

Perform this task to configure a PPPoE client on an Ethernet interface.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface ethernet number

4. pppoe-client dial-pool-number number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface ethernet number Example: Router(config)# interface ethernet 0	Configures an Ethernet interface.
Step 4	pppoe-client dial-pool-number number Example: Router(config-if)# pppoe-client dial-pool-number 1	Configures the PPPoE client and specifies the dialer interface to use for cloning.

Configuring the Dialer Interface

Perform this task to configure the dialer interface to be used for cloning on the PVC.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface dialer number

4. mtu bytes

5. ip address negotiated

6. dialer pool number

7. dialer-group group-number

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	configure terminal Example: Router# configure terminal	Enters global configuration mode.
Step 3	interface dialer number Example: Router(config)# interface dialer 1	Configures a dialer interface.
Step 4	mtu bytes Example: Router(config-if) mtu 1492	Adjusts the maximum packet size or maximum transmission unit (MTU) size. Note It is recommended that you set the MTU to 1492 bytes. This value accommodates a PPPoE header encapsulation of 8 bytes in the Ethernet frame payload
Step 5	ip address negotiated Example: Router(config-if)# ip address negotiated	Specifies that the IP address for the interface is obtained via PPP/IPCP address negotiation.
Step 6	dialer pool number Example: Router(config-if)# dialer pool 1	Specifies the dialing pool to use to connect to a specific destination subnetwork.
Step 7	dialer-group group-number Example: Router(config-if)# dialer-group 1	Configures an interface to belong to a specific dialing group.

Clearing PPPoE Client Sessions

Perform this task to clear PPPoE client sessions.

Restrictions

This task applies only to Cisco IOS release 12.2(13)T and later releases.

SUMMARY STEPS

1. enable

2. clear pppoe {interface type number [vc {[vpi/]vci | vc-name}] | rmac mac-address | all}

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	clear pppoe {interface type number [vc {[vpi/]vci | vc-name}] | rmac mac-address | all} Example: Router# clear pppoe all	Clears the PPPoE client session and causes the PPPoE client to try immediately to reestablish the session.

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Note To permanently terminate a PPPoE client session, use the no pppoe-client dial-pool-number command in interface configuration mode or interface-atm-vc configuration mode.

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Verifying the PPPoE Client

Perform this task to verify PPPoE client configuration.

Prerequisites

This task assumes that the PPPoE client has been configured.

Restrictions

This task applies only to Cisco IOS release 12.2(13)T and later releases.

SUMMARY STEPS

1. enable

2. show pppoe session [all | packets]

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	show pppoe session [all | packets] Example: Router# show pppoe session	Displays information about currently active PPPoE sessions.

Troubleshooting PPPoE Client Sessions

Perform this task to troubleshoot the PPPoE client.

Prerequisites

This task applies only to Cisco IOS Release 12.2(13)T and later releases.

SUMMARY STEPS

1. enable

2. debug pppoe {data | errors | events | packets}

DETAILED STEPS

	Command or Action	Purpose
Step 1	enable Example: Router> enable	Enables privileged EXEC mode. •Enter your password if prompted.
Step 2	debug pppoe {data | errors | events | packets} Example: Router# debug pppoe errors	Displays debugging information for PPPoE sessions.

Configuration Examples for PPPoE Client

This section contains the following examples:

•PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T: Examples

•PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases: Example

PPPoE Client in Releases Prior to Cisco IOS Release 12.2(13)T: Examples

In the following example, a PPPoE client is configured on a PVC on ATM interface 0. The PPPoE client will use dialer interface 1 as its virtual access interface.

vpdn enable

vpdn-group 1

 request-dialin

  protocol pppoe

! 

interface atm0

 pvc 1/100

  pppoe-client dial-pool-number 1

!

interface dialer 1

 ip address negotiated

 dialer pool 1

 dialer-group 1

!

In the following example, two PPPoE client sessions are configured on an Ethernet interface. Each PPPoE client will use a separate dialer interface and a separate dialer pool.

vpdn enable

vpdn-group 1

 request-dialin

  protocol pppoe

! 

interface ethernet1/1

 pppoe-client dial-pool-number 1

 pppoe-client dial-pool-number 2

!

interface dialer 1

 ip address negotiated

 dialer pool 1

 dialer-group 1

!

interface dialer 2

 ip address negotiated

 dialer pool 2

 dialer-group 2

PPPoE Client in Cisco IOS Release 12.2(13)T and Later Releases: Example

The following example shows how to configure a PPPoE client on an Ethernet interface. Note that in Releases 12.2(13)T and later it is not necessary to configure a global VPDN group before configuring the PPPoE client.

interface Ethernet 0

 pppoe-client dial-pool-number 1

interface Dialer 1

 ip address negotiated

 dialer pool 1

 mtu 1492

Additional References

The following sections provide references related to PPPoE client configuration.

Related Documents

Related Topic	Document Title
VPDN configuration	Cisco IOS Dial Technologies Configuration Guide, Release 12.2
VPDN commands	Cisco IOS Dial Technologies Command Reference, Release 12.2
PPPoE configuration	Cisco IOS Wide-Area Networking Configuration Guide, Release 12.2
PPPoE commands	Cisco IOS Wide-Area Networking Command Reference, Release 12.2

Standards

Standard	Title
No new or modified standards are supported by this feature.	—

MIBs

MIB	MIBs Link
No new or modified MIBs are supported by this feature.	To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs

RFCs

RFC	Title
RFC 2516	A Method for Transmitting PPP over Ethernet (PPPoE)

Technical Assistance

Description	Link
The Cisco Technical Support website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.	http://www.cisco.com/techsupport

Command Reference

This section documents new and modified commands only. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications.

•clear vpdn tunnel

•pppoe-client dial-pool-number

clear vpdn tunnel

To shut down a specifiedvirtual private dial-up network (VPDN) tunnel and all sessions within the tunnel, use the clear vpdn tunnel command in privileged EXEC mode.

L2TP or PPTP Tunnels

clear vpdn tunnel {pptp | l2tp} {all | hostname remote-name [local-name] | id local-id | ip local-ip-address | ip remote-ip-address}

L2F Tunnels

clear vpdn tunnel l2f {all | hostname nas-name hgw-name | id local-id | ip local-ip-address | ip remote-ip-address}

Syntax Description

pptp	Clears the specified Point-to-Point Tunneling Protocol (PPTP) tunnel.
l2tp	Clears the specified Layer 2 Tunneling Protocol (L2TP) tunnel.
all	Clears all VPDN tunnels terminating on the device.
hostname remote-name [local-name]	Clears all L2TP or PPTP VPDN tunnels established between the devices with the specified local and remote hostnames.
id local-id	Clears the VPDN tunnel with the specified local ID.
ip local-ip-address	Clears all VPDN tunnels terminating on the device with the specified local IP address.
ip remote-ip-address	Clears all VPDN tunnels terminating on the device with the specified remote IP address.
l2f	Clears the specified Layer 2 Forwarding (L2F) tunnel.
hostname nas-name hgw-name	Clears all L2F VPDN tunnels established between the network access server (NAS) and home gateway with the specified hostnames.

Command Modes

Privileged EXEC

Command History

Release	Modification
11.2	This command was introduced.
11.3(5)AA	The l2tp keyword was added.
12.0(1)T	The l2f keyword was added.
12.0(5)XE5	The pptp keyword was added.
12.1(5)T	The pptp keyword was updated for additional Cisco access servers or routers.
12.2(2)T	The syntax for this command was modified to include the following keywords and arguments: •all •hostname remote-name local-name •hostname nas-name hgw-name •id local-id •ip local-ip-address •ip remote-ip-address

Usage Guidelines

Manual termination of a VPDN tunnel results in the immediate shutdown of the specified VPDN tunnel and all sessions within that tunnel, resulting in a sudden disruption of VPDN services.

You can shut down VPDN tunnels more gradually by issuing the vpdn softshut command, which prevents the establishment of new VPDN sessions in all VPDN tunnels that terminate on the device. Existing VPDN sessions are not affected.

A manually terminated VPDN tunnel can be restarted immediately when a user logs in. Manually terminating and restarting a VPDN tunnel while VPDN event logging is enabled can provide useful troubleshooting information about VPDN session establishment. VPDN event logging is enabled by issuing the vpdn logging command.

Examples

The following example clears all L2TP tunnels connecting to a remote peer named NAS1:

Router# clear vpdn tunnel l2tp hostname NAS1

The following example clears all PPTP tunnels connecting the devices with the hostnames NAS3 and tun1:

Router# clear vpdn tunnel pptp NAS3 hostname tun1

The following example clears all L2F tunnels originating from the specified IP address:

Router# clear vpdn tunnel l2f ip 10.1.1.1

Related Commands

Command	Description
vpdn logging	Enables the logging of generic VPDN events.
vpdn softshut	Prevents new sessions from being established on a VPDN tunnel without disturbing existing sessions.

pppoe-client dial-pool-number

To configure a PPP over Ethernet (PPPoE) client and to specify dial-on-demand routing (DDR) functionality, use the pppoe-client dial-pool-number command in either interface configuration mode or ATM virtual circuit configuration mode. To disable any configured functionality, use the no form of this command.

pppoe-client dial-pool-number number [dial-on-demand]

no pppoe-client dial-pool-number number [dial-on-demand]

Syntax Description

number	Unique number of a dial group configured with the dialer-group dialer interface command.
dial-on-demand	(Optional) Enables DDR functionality for the PPPoE connection.

Defaults

A PPPoE client is not configured, and DDR functionality is disabled.

Command Modes

Interface configuration
ATM virtual circuit configuration

Command History

Release	Modification
12.1(3)XG	This command was introduced.
12.2(2)T	This command was integrated into Cisco IOS Release 12.2(2)T.
12.2(13)T	The dial-on-demand keyword was added to allow the configuration of DDR interesting traffic control list functionality.

Usage Guidelines

One permanent virtual circuit (PVC) will support only one PPPoE client. Multiple PPPoE clients can run concurrently on different permanent virtual circuits (PVCs), but each PPPoE client must use a separate dialer interface and a separate dialer pool.

Use this command to configure dial-on-demand routing (DDR) interesting traffic control list functionality of the dialer interface with a PPP over Ethernet (PPPoE) client. When the DDR functionality is configured for this command, the following DDR commands must also be configured: dialer-group, dialer hold-queue, dialer idle-timeout, and dialer-list.

Tips for Configuring the Dialer Interface

If you are configuring a hard-coded IP address under the dialer interface, you can configure a default IP route using the ip route command as follows:

ip route 0.0.0.0 0.0.0.0 dialer1

But if you are configuring a negotiated IP address using the ip address negotiated command under the dialer interface, you must configure a default IP route using the ip route command as follows:

ip route 0.0.0.0 0.0.0.0 dialer1 permanent

The reason is that the dialer interface will lose its IP address when a PPPoE session is brought down (even if the dialer does not go down), and hence the route removal routine will take effect and remove all IP routes pointed at the dialer interface, even the default IP route. Although the default IP route will be added back about one minute later by IP background processes, you may risk losing incoming packets during the interval.

Examples

PPPoE Client DDR Idle-Timer on an Ethernet Interface

The following example shows how to configure the PPPoE client DDR idle-timer on an Ethernet interface and includes the required DDR commands:

!

vpdn enable

no vpdn logging

!

vpdn-group 1

 request-dialin

  protocol pppoe

!

interface Ethernet1

 pppoe enable

 pppoe-client dial-pool-number 1 dial-on-demand

!

interface Dialer1

 ip address negotiated

 ip mtu 1492

 encapsulation ppp

 dialer pool 1

 dialer idle-timeout 180 either

 dialer hold-queue 100

 dialer-group 1

!

dialer-list 1 protocol ip permit

!         

ip route 0.0.0.0 0.0.0.0 Dialer1

PPPoE client DDR Idle-Timer on an ATM PVC

The following example shows how to configure the PPPoE client DDR idle-timer on an ATM PVC interface and includes the required DDR commands:

!

vpdn enable

no vpdn logging

!

vpdn-group 1

 request-dialin

  protocol pppoe

!

interface ATM2/0

 pvc 2/100 

  pppoe-client dial-pool-number 1 dial-on-demand

!

interface Dialer1

 ip address negotiated

 ip mtu 1492

 encapsulation ppp

 dialer pool 1

 dialer idle-timeout 180 either

 dialer hold-queue 100

 dialer-group 1

!

dialer-list 1 protocol ip permit

!         

ip route 0.0.0.0 0.0.0.0 Dialer1

Related Commands

Command	Description
debug vpdn pppoe-data	Displays PPPoE session data packets.
debug vpdn pppoe-errors	Displays PPPoE protocol errors that prevent a session from being established or errors that cause an established session to be terminated.
debug vpdn pppoe-events	Displays PPPoE protocol messages about events that are part of normal session establishment or shutdown.
debug vpdn pppoe-packets	Displays each PPPoE protocol packet exchanged.
dialer-group	Controls access by configuring a virtual access interface to belong to a specific dialing group.
dialer hold-queue	Allows interesting outgoing packets to be queued until a modem connection is established.
dialer idle-timeout	Specifies the idle time before the line is disconnected.
dialer-list	Defines a DDR dialer list to control dialing by protocol or by a combination of protocol and an access list.